Merge remote-tracking branch 'origin/main' into HEAD

docs: remove the README build section
chore: v0.1.33
2026-11-07 18:38:33 -10:00 · 2026-11-01 18:59:17 +08:00 · 2026-11-01 18:46:40 +08:00 · 2026-11-01 18:35:25 +08:00 · 2026-11-01 18:26:24 +08:00 · 2026-11-01 18:05:05 +08:00
1233 changed files with 98494 additions and 7289 deletions
@@ -3,6 +3,8 @@ on:
  push:
    branches: [main]
  pull_request:
+    branches: [main]
+    types: [opened, synchronize, reopened]
  workflow_dispatch:

 concurrency:
@@ -69,6 +71,15 @@ jobs:
      - run: cargo build --locked -p ide-host --bin openidea-server --target x86_64-unknown-linux-musl
      - run: target/x86_64-unknown-linux-musl/debug/openidea-server --version

+  deny:
+    name: Cargo deny
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dtolnay/rust-toolchain@stable
+      - uses: taiki-e/install-action@cargo-deny
+      - run: cargo deny check
+
  frontend:
    name: Frontend
    runs-on: ubuntu-22.04
@@ -82,6 +93,7 @@ jobs:
      - run: pnpm typecheck
      - run: pnpm lint
      - run: pnpm format:check
+      - run: pnpm knip
      - run: pnpm test
      - run: pnpm build

@@ -70,6 +70,12 @@ jobs:
          - name: Linux x64
            os: ubuntu-22.04
            target: x86_64-unknown-linux-gnu
+          - name: Linux arm64
+            os: ubuntu-22.04-arm
+            target: aarch64-unknown-linux-gnu
+          - name: Windows arm64
+            os: windows-11-arm
+            target: aarch64-pc-windows-msvc
          - name: Windows x64
            os: windows-latest
            target: x86_64-pc-windows-msvc
@@ -196,11 +202,16 @@ jobs:
            }
            // Bundle suffix → updater platform keys, as tauri-action names them.
            const kinds = [
+              [/_aarch64\.AppImage$/, ["linux-aarch64", "linux-aarch64-appimage"]],
+              [/_arm64\.deb$/, ["linux-aarch64-deb"]],
+              [/\.aarch64\.rpm$/, ["linux-aarch64-rpm"]],
              [/_amd64\.AppImage$/, ["linux-x86_64", "linux-x86_64-appimage"]],
              [/_amd64\.deb$/, ["linux-x86_64-deb"]],
              [/\.x86_64\.rpm$/, ["linux-x86_64-rpm"]],
              [/_aarch64\.app\.tar\.gz$/, ["darwin-aarch64", "darwin-aarch64-app"]],
              [/_x64\.app\.tar\.gz$/, ["darwin-x86_64", "darwin-x86_64-app"]],
+              [/_arm64_en-US\.msi$/, ["windows-aarch64", "windows-aarch64-msi"]],
+              [/_arm64-setup\.exe$/, ["windows-aarch64-nsis"]],
              [/_x64_en-US\.msi$/, ["windows-x86_64", "windows-x86_64-msi"]],
              [/_x64-setup\.exe$/, ["windows-x86_64-nsis"]],
            ];
@@ -9,6 +9,7 @@
    "dist",
    "target",
    "src/bindings.ts",
+    "src/editor/core/cm/angular/parser*.ts",
    "docs/plugins/themes.md",
    "pnpm-lock.yaml",
    "**/*.toml",
@@ -13,6 +13,7 @@
    "src-tauri",
    "crates",
    "src/bindings.ts",
+    "src/editor/core/cm/angular/parser*.ts",
    "fixtures",
    "plugins",
    "test-results",
@@ -3,7 +3,7 @@ resolver = "3"
 members = ["crates/*", "src-tauri"]

 [workspace.package]
-version = "0.1.25"
+version = "0.1.33"
 edition = "2024"
 rust-version = "1.96"
 license = "Apache-2.0"
@@ -40,6 +40,7 @@ ide-fonts = { path = "crates/ide-fonts" }
 ide-ssh = { path = "crates/ide-ssh" }
 ide-remote = { path = "crates/ide-remote" }
 ide-host = { path = "crates/ide-host" }
+ide-notebook = { path = "crates/ide-notebook" }

 # serialization & IPC typing
 serde = { version = "1", features = ["derive"] }
@@ -75,6 +76,7 @@ trash = "5"
 blake3 = "1"
 dunce = "1"
 dirs = "6"
+zip = { version = "9", default-features = false, features = ["deflate"] }

 # search, index, language
 grep-searcher = "0.1"
@@ -85,6 +87,9 @@ redb = "4"
 tree-sitter = "0.25"

 # protocols & integrations
+jupyter-zmq-client = { version = "=2.0.0", default-features = false, features = ["tokio-runtime", "ring"] }
+jupyter-protocol = "=2.0.3"
+zeromq = { version = "0.6", default-features = false, features = ["tokio-runtime", "tcp-transport"] }
 lsp-types = "0.97"
 gix = { version = "0.89", default-features = false }
 portable-pty = "0.9"
@@ -92,6 +97,8 @@ reqwest = { version = "0.13", default-features = false, features = ["rustls-no-p
 rustls = { version = "0.23", default-features = false, features = ["ring", "std", "tls12", "logging"] }
 rustls-platform-verifier = "0.7"
 sqlx = { version = "0.9", default-features = false, features = ["runtime-tokio", "tls-rustls-ring-webpki", "sqlite", "postgres", "mysql"] }
+tiberius = { version = "0.13", default-features = false, features = ["tds73", "rustls", "sql-browser-tokio"] }
+bb8 = "0.9"
 uuid = { version = "1", features = ["v4"] }

 # testing
@@ -14,7 +14,7 @@
  &nbsp;·&nbsp;
  <a href="#benchmark">Benchmark</a>
  &nbsp;·&nbsp;
-  <a href="#build">Build</a>
+  <a href="https://discord.gg/2Zy4yn7gP">Discord</a>
 </p>

 https://github.com/user-attachments/assets/234dd54c-1255-4b3a-b35c-533d78d737c0
@@ -45,15 +45,6 @@ IDEA analyses Python more deeply, so "ready" doesn't mean the same work on
 both sides. Both are measured from the outside, the same way: see
 [`perf/compare`](perf/compare) to run it on your machine and projects.

-## Build
-
-```sh
-pnpm install
-pnpm tauri dev
-```
-
-Rust 1.96, Node 22, pnpm and the [Tauri prerequisites](https://v2.tauri.app/start/prerequisites/).
-
 ## License

 [Apache 2.0](LICENSE). Bundled third-party assets are listed in [`THIRD_PARTY_LICENSES.md`](THIRD_PARTY_LICENSES.md).
@@ -1,5 +1,13 @@
 # Third-party licenses

+## Project Lombok
+
+`plugins/lombok/lombok-1.18.48-openidea.1.jar` contains Project Lombok v1.18.48 with the Equinox
+classloader fix from [projectlombok/lombok#4059](https://github.com/projectlombok/lombok/pull/4059).
+Copyright (C) 2009-2021 The Project Lombok Authors. MIT license and bundled component
+notices are retained in [plugins/lombok/LICENSE](plugins/lombok/LICENSE) and inside the jar.
+Source tag, patch commits and build instructions: [plugins/lombok/README.md](plugins/lombok/README.md).
+
 ## JetBrains IntelliJ Platform icons

 `src/ui/expui/**` contains SVG icons from the IntelliJ Platform "new UI" (expui)
@@ -12,12 +20,13 @@ icon set, copied unmodified (some renamed) from JetBrains' open-source repositor
  `python/python-requirements` (`fileTypes/requirements`); `python/pipenv`
  (`fileTypes/pipenv`); `python/python-pyproject` (`expui/toml.svg` →
  `fileTypes/pyprojectToml`); `plugins/kotlin/base` (`fileTypes/kotlin`,
-  `kotlinScript`, `kotlinGradleScript`); `java/openapi` (`fileTypes/maven`);
+  `kotlinScript`, `kotlinGradleScript`, `icons/expui/objectKotlin` → `kotlin/objectKotlin`); `java/openapi` (`fileTypes/maven`);
  `plugins/markdown` (`fileTypes/markdown`); `plugins/toml` (`fileTypes/toml`);
  `plugins/terminal` (`toolwindows/terminal`); `plugins/maven`
  (`images/expui/toolwindow/maven` → `toolwindows/maven`, `images/expui/build/maven*`
  → `maven/`); `plugins/gradle` (`icons/expui/gradle` → `toolwindows/gradle`,
-  `icons/expui/gradleLoadChanges` → `build/gradleLoadChanges`);
+  `icons/expui/gradleLoadChanges` → `build/gradleLoadChanges`,
+  `icons/expui/gradle`, `icons/gradleSubproject` → `gradle/`);
  `platform/external-system-impl` (`icons/newui/task` → `externalSystem/task`).
  Copyright 2000-2026 JetBrains s.r.o. and contributors. Apache License 2.0 (below).
 - [intellij-plugins](https://github.com/JetBrains/intellij-plugins) (each plugin
@@ -26,6 +35,20 @@ icon set, copied unmodified (some renamed) from JetBrains' open-source repositor
  `fileTypes/hashiCorp`, Apache-2.0); `makefile` (`expui/makefile` →
  `fileTypes/makefile`, MIT, Copyright (c) 2016 Victor Kropp — full text below).

+The read/write usage filter assets (`actions/showReadAccess{,_dark}.svg` and
+`actions/showWriteAccess{,_dark}.svg`) are copied unmodified from
+`platform/icons/src/expui/actions/` at intellij-community commit
+[`e992ff4750b4c36afe2caadfa8b191a8f36fb7a2`](https://github.com/JetBrains/intellij-community/tree/e992ff4750b4c36afe2caadfa8b191a8f36fb7a2/platform/icons/src/expui/actions).
+Their original copyright headers and Apache-2.0 licensing are retained.
+
+- [intellij-rust](https://github.com/intellij-rust/intellij-rust) (MIT):
+  `src/main/resources/icons/expui/rustFile{,_dark}.svg` →
+  `src/ui/expui/fileTypes/rust{,_dark}.svg`;
+  `src/main/resources/icons/expui/cargo{,_dark}.svg` and `cargoLock{,_dark}.svg` →
+  `src/ui/expui/fileTypes/cargo{,_dark}.svg` and `cargoLock{,_dark}.svg`.
+  Copyright (c) 2015 Aleksey Kladov, Evgeny Kurbatsky, Alexey Kudinkin and contributors;
+  Copyright (c) 2016 JetBrains. MIT licence, full text below.
+
 At render time `src/ui/icons.tsx` may recolour monochrome icons to `currentColor`.

 ## JetBrains IntelliJ Platform diff algorithm
@@ -42,7 +65,7 @@ from its tests (`LineComparisonUtilTest`, `WordComparisonUtilTest`,
 JetBrains s.r.o. and contributors. Apache License 2.0 (below).

 `src/ui/openidea/**` holds OpenIDEA's own file-type icons drawn in the expui style for
-languages whose JetBrains icons are not open source (Go, Rust, Ruby, Dart, Lua, Zig,
+languages whose JetBrains icons are not open source (Go, Ruby, Dart, Lua, Zig,
 Svelte, …). Those using the page-with-corner-badge layout (`goMod`, `goWork`,
 `dotenv`, `readme`, `lock`, `license`) reuse the page outline of the Apache-2.0
 expui `fileTypes/h.svg`; that outline is modified from the original by JetBrains.
@@ -53,6 +76,31 @@ The lettering in `src-tauri/icons/source/openidea-wordmark*.svg` is outlined fro
 Inter Tight (Copyright 2022 The Inter Project Authors, SIL Open Font License 1.1,
 https://github.com/rsms/inter-tight).

+### MIT License (Rust and Cargo icons)
+
+The MIT License (MIT)
+
+Copyright (c) 2015 Aleksey Kladov, Evgeny Kurbatsky, Alexey Kudinkin and contributors
+Copyright (c) 2016 JetBrains
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+
 ### MIT License (makefile icon)

 Copyright (c) 2016 Victor Kropp
@@ -111,6 +159,18 @@ shell and css dictionaries of [cspell-dicts](https://github.com/streetsidesoftwa
 (October 2026): lowercased, filtered and merged by OpenIDEA. Copyright Street Side Software;
 MIT licence, full text in `crates/ide-spell/src/dict/LICENSE-cspell-dicts`.

+## CodeMirror Angular template language
+
+`src/editor/core/cm/angular/` (`angular.grammar`, `tokens.ts`, `index.ts` and the
+`parser.ts` generated from them) is derived from
+[@codemirror/lang-angular](https://github.com/codemirror/lang-angular) 0.1.4
+(commit `ecc5038f`). Copyright (C) 2018-2021 by Marijn Haverbeke and others; MIT
+licence, full text in `src/editor/core/cm/angular/LICENSE`. Modifications by
+OpenIDEA: control-flow blocks (`@if`, `@for`, `@switch`, `@defer`, ...) and `@let`
+declarations, key and animation binding names (`(keydown.enter)`, `[@fade]`,
+`(@fade.done)`), runs of text that entities split (`a && b`) parsed as one, and one
+token for `{` and `}`.
+
 ## nvim-treesitter queries

 `crates/ide-syntax/queries/<grammar>/locals.scm` are derived from the `locals.scm`
@@ -6,6 +6,8 @@ edition.workspace = true
 license.workspace = true

 [dependencies]
+encoding_rs.workspace = true
+ide-vfs.workspace = true
 ide-core.workspace = true
 ide-jsonrpc.workspace = true
 ide-vcs.workspace = true
@@ -147,6 +147,7 @@ async fn a_task_runs_on_a_v2_agent_and_resumes_its_session() {
    let mgr = manager(tmp.path(), agent.clone());
    let task = mgr
        .create(NewAgentTask {
+            project_root: None,
            prompt: text("Use the TodoWrite tool"),
            provider: "claude-acp".into(),
            config: vec![AgentConfigChoice { id: "model".into(), value: "haiku".into() }],
@@ -37,6 +37,16 @@ pub(crate) fn bypass_approvals(provider: &str, config: &[AgentConfigOption]) ->
    provider == "cursor" && config.iter().any(|o| o.id == CURSOR_APPROVAL && o.current.as_deref() == Some("bypass"))
 }

+/// The mode that approves everything without asking (`bypassPermissions`, `yolo`, `full-access`…), if the agent has one.
+pub(crate) fn bypass_mode(options: &[AgentConfigOption]) -> Option<(&AgentConfigOption, &AgentConfigValue)> {
+    let option = options.iter().find(|o| o.category.as_deref() == Some("mode"))?;
+    let value = option.values.iter().find(|v| {
+        let m: String = v.value.to_lowercase().chars().filter(char::is_ascii_lowercase).collect();
+        m.contains("bypass") || m == "yolo" || m.contains("fullaccess") || m == "dangerous"
+    })?;
+    Some((option, value))
+}
+
 /// The settings in a `session/new` or `session/load` result: its select `configOptions`,
 /// plus the older `modes` / `models` fields for what those don't cover.
 pub(crate) fn options_of(result: &Value) -> Vec<AgentConfigOption> {
@@ -23,6 +23,7 @@ pub use model::*;
 use conversation::{Conversation, SavedSubagent, Session};
 use ide_core::{IdeError, IdeResult, IpcPath};
 use ide_jsonrpc::{Framing, Handler, Peer, RpcError, codes};
+use ide_vcs::Repo;
 use parking_lot::{Mutex, RwLock};
 use serde::{Deserialize, Serialize};
 use serde_json::{Value, json};
@@ -116,9 +117,13 @@ impl Shared {
    fn known_config(&self, provider: &str) -> Vec<AgentConfigOption> {
        let mut config = self.known.lock().get(provider).map(|k| k.config.clone()).unwrap_or_default();
        config::add_client_options(provider, &mut config);
-        // Approval bypass belongs to the conversation, never to another new task.
+        if let Some((o, v)) = config::bypass_mode(&config).map(|(o, v)| (o.id.clone(), v.value.clone()))
+            && let Some(o) = config.iter_mut().find(|c| c.id == o)
+        {
+            o.current = Some(v);
+        }
        if let Some(o) = config.iter_mut().find(|o| o.id == config::CURSOR_APPROVAL) {
-            o.current = Some("ask".into());
+            o.current = Some("bypass".into());
        }
        config
    }
@@ -314,8 +319,8 @@ impl AgentManager {
    }

    /// The slash commands to complete for `provider`, in `task`'s directory or (without one)
-    /// in the project: what the agent offered last time there, plus, for Claude Code, the
-    /// skills and custom commands on disk it has not listed.
+    /// in the project: what the agent offered last time there, unadvertised builtins,
+    /// and, for Claude Code, skills and custom commands on disk it has not listed.
    pub async fn commands(&self, provider: &str, task: Option<&str>) -> IdeResult<Vec<AgentCommand>> {
        let (provider, offered, cwd) = match task {
            Some(id) => {
@@ -325,6 +330,14 @@ impl AgentManager {
            }
            None => (provider.to_owned(), self.shared.known_commands(provider), self.shared.paths.project_root.clone()),
        };
+        // Commands the agent implements itself and never lists (its CLI builtins):
+        // merged without duplicating what `availableCommands` or the disk offer.
+        let mut offered = offered;
+        for &(name, description) in builtin_commands(&provider) {
+            if !offered.iter().any(|c| c.name == name) {
+                offered.push(AgentCommand { name: name.to_owned(), description: description.to_owned(), hint: None });
+            }
+        }
        if provider != "claude" && provider != "claude-acp" {
            return Ok(offered);
        }
@@ -353,9 +366,16 @@ impl AgentManager {
            .ok_or_else(|| IdeError::invalid(format!("unknown agent {}", req.provider)))?;
        let prompt = clean(req.prompt).ok_or_else(|| IdeError::invalid("describe the task first"))?;
        let title = title_of(&prompt);
-        let root = self.shared.paths.project_root.clone();
+        let root = req.project_root.clone().map(|p| p.0).unwrap_or_else(|| self.shared.paths.project_root.clone());
+        let project_root = Some(IpcPath(root.clone()));
        let (cwd, branch, base, base_commit, before) = match req.isolation {
            Isolation::Worktree => {
+                // The UI offers worktrees for git projects only; state it when it isn't one.
+                if Repo::discover(&root)?.is_none() {
+                    return Err(IdeError::invalid(
+                        "worktrees need a git repository: run the task in the local checkout",
+                    ));
+                }
                let dir = self.shared.paths.worktrees_dir.clone();
                let (t, b) = (title.clone(), req.base.clone());
                let c = blocking(move || worktree::create(&root, &dir, &t, b.as_deref())).await?;
@@ -379,6 +399,7 @@ impl AgentManager {
        }
        let now = now_ms();
        let task = AgentTask {
+            project_root,
            id: uuid::Uuid::new_v4().simple().to_string(),
            title,
            provider: spec.id.clone(),
@@ -539,6 +560,10 @@ impl AgentManager {
                o.current = Some(value);
            }
            s.task.model = model_of(&s.task.config).or(s.task.model.take());
+            let provider = s.task.provider.clone();
+            let config = s.task.config.clone();
+            drop(s);
+            task.shared.remember(&provider, Some(&config), None);
        }
        task.approve_pending();
        task.persist();
@@ -748,18 +773,41 @@ impl AgentManager {
        Ok(())
    }

+    /// Returns an archived task to the active list without starting the agent.
+    pub fn unarchive(&self, id: &str) -> IdeResult<()> {
+        let task = self.task(id)?;
+        {
+            let mut s = task.state.lock();
+            if s.task.status != AgentStatus::Archived {
+                return Ok(());
+            }
+            if s.busy {
+                return Err(IdeError::invalid("the task is still stopping"));
+            }
+            s.task.status = AgentStatus::Ready;
+            s.task.error = None;
+            s.task.updated_ms = now_ms();
+        }
+        task.persist();
+        task.emit_task();
+        Ok(())
+    }
+
    /// Forgets the task; with `remove_worktree` also deletes its worktree (the branch stays).
    pub async fn delete(&self, id: &str, remove_worktree: bool) -> IdeResult<()> {
        let task = self.task(id)?;
        task.kill();
-        let (isolation, cwd) = {
+        let (isolation, cwd, root) = {
            let s = task.state.lock();
-            (s.task.isolation, s.task.cwd.0.clone())
+            (
+                s.task.isolation,
+                s.task.cwd.0.clone(),
+                s.task.project_root.clone().map(|p| p.0).unwrap_or_else(|| self.shared.paths.project_root.clone()),
+            )
        };
        // A copy of the task (a fork) may work in the same worktree.
        let shared = self.tasks.read().values().any(|t| t.id != id && t.state.lock().task.cwd.0 == cwd);
        if remove_worktree && !shared && isolation == Isolation::Worktree && cwd.exists() {
-            let root = self.shared.paths.project_root.clone();
            blocking(move || worktree::remove(&root, &cwd)).await?;
        }
        self.tasks.write().remove(id);
@@ -1017,6 +1065,7 @@ impl Task {
        self.push_entry(AgentEntry::User {
            text: prompt.text,
            attachments,
+            images: prompt.images,
            sent_ms: Some(now_ms()),
            done_ms: None,
            steered: true,
@@ -1037,6 +1086,7 @@ impl Task {
        self.push_entry(AgentEntry::User {
            text: prompt.text.clone(),
            attachments,
+            images: prompt.images.clone(),
            sent_ms: Some(now_ms()),
            done_ms: None,
            steered: false,
@@ -1183,7 +1233,6 @@ impl Task {
            (if known { reported } else { s.task.config.clone() }, s.wanted.clone())
        };
        config::add_client_options(&provider_id, &mut options);
-        self.shared.remember(&provider_id, Some(&options), None);
        for choice in &wanted {
            // An option the session doesn't offer yet is set once it does (`apply_late_choices`).
            let Some(o) = options.iter().find(|o| o.id == choice.id).cloned() else { continue };
@@ -1212,6 +1261,7 @@ impl Task {
                Err(e) => tracing::warn!("agent task {}: setting {} to {} failed: {e}", self.id, o.id, choice.value),
            }
        }
+        self.shared.remember(&provider_id, Some(&options), None);
        {
            let mut s = self.state.lock();
            s.task.model = model_of(&options).or(s.task.model.take());
@@ -1629,6 +1679,16 @@ fn model_of(config: &[AgentConfigOption]) -> Option<String> {
    config.iter().find(|o| o.category.as_deref() == Some("model")).and_then(|o| o.current.clone())
 }

+/// Commands the agent implements on its own and never lists in `availableCommands` —
+/// its CLI builtins, passed through as prompt text (e.g. `/compact`). `(name, description)`.
+fn builtin_commands(provider: &str) -> &'static [(&'static str, &'static str)] {
+    match provider {
+        // OpenCode ACP handles `/compact` via session.summarize but omits it from its command list.
+        "opencode" => &[("compact", "compact the conversation")],
+        _ => &[],
+    }
+}
+
 fn file_name(path: &Path) -> String {
    path.file_name().map_or_else(|| path.to_string_lossy().into_owned(), |n| n.to_string_lossy().into_owned())
 }
@@ -47,6 +47,9 @@ pub enum Isolation {
 #[derive(Clone, Debug, Serialize, Deserialize, Type)]
 #[serde(rename_all = "camelCase")]
 pub struct AgentTask {
+    /// Original project folder; absent in tasks saved before per-task roots.
+    #[serde(default)]
+    pub project_root: Option<IpcPath>,
    pub id: String,
    pub title: String,
    /// [`AgentProvider::id`].
@@ -240,6 +243,9 @@ pub enum AgentEntry {
        text: String,
        /// Names of the files and images sent with it.
        attachments: Vec<String>,
+        /// The images sent with it, shown in the conversation.
+        #[serde(default)]
+        images: Vec<AgentImage>,
        /// When it was sent (ms since the epoch); `None` in tasks saved before this was kept.
        #[serde(default)]
        sent_ms: Option<f64>,
@@ -361,6 +367,9 @@ pub struct AgentProbe {
 #[derive(Clone, Debug, Serialize, Deserialize, Type)]
 #[serde(rename_all = "camelCase")]
 pub struct NewAgentTask {
+    /// Validated by the host; defaults to the window project root.
+    #[serde(default)]
+    pub project_root: Option<IpcPath>,
    pub prompt: AgentPrompt,
    pub provider: String,
    /// Settings for the new session (model, mode…).
@@ -296,7 +296,7 @@ impl Shim {
        let mut cmd = std::process::Command::new(&self.config.program);
        ide_core::process::prepare(&mut cmd);
        let out = cmd.arg("--version").envs(ide_core::process::shell_env()).output().ok()?;
-        let text = String::from_utf8_lossy(&out.stdout);
+        let text = ide_core::output_encoding::decode_tool_output(&out.stdout);
        text.split_whitespace().next().filter(|v| out.status.success() && !v.is_empty()).map(str::to_owned)
    }

@@ -915,7 +915,11 @@ impl Session {
                        } else {
                            "end_turn"
                        };
-                        finished = st.turn.take().map(|t| (t, TurnEnd::Stop(stop)));
+                        finished = st.turn.take().map(|mut t| {
+                            // Claude Code reports a turn that failed as cancelled here.
+                            let failure = t.failure.take().filter(|_| !t.cancelled);
+                            (t, failure.unwrap_or(TurnEnd::Stop(stop)))
+                        });
                    }
                }
                "assistant" if msg.get("parent_tool_use_id").is_none_or(Value::is_null) => {
@@ -1139,7 +1143,8 @@ where
 /// Whether `result` ends `turn`: it answers the turn's last message, or (stopped) any of
 /// its messages, or names none (the CLI's own error before the turn began).
 fn belongs(turn: &Turn, result: &Value) -> bool {
-    if result.get("origin").is_some_and(|o| !o.is_null()) {
+    // Prompts are sent with the origin `human`, and their results echo it.
+    if result.get("origin").is_some_and(|o| !o.is_null() && o.get("kind").and_then(Value::as_str) != Some("human")) {
        return false;
    }
    let mut uuids = strings(result.get("user_message_uuids"));
@@ -738,6 +738,50 @@ async fn a_stop_ahead_of_its_prompt_cancels_it() {
    assert!(cli.sent.lock()[0].iter().all(|m| m["type"] != "user"), "nothing was sent");
 }

+#[tokio::test(flavor = "multi_thread")]
+async fn a_failed_turn_reports_its_failure() {
+    let text = "Failed to authenticate: OAuth session expired and could not be refreshed";
+    let lifecycle = |uuid: &str, state: &str| {
+        Frame::Cli(json!({ "type": "command_lifecycle", "command_uuid": uuid, "state": state }))
+    };
+    let result = |uuid: &str| {
+        Frame::Cli(json!({
+            "type": "result", "subtype": "success", "is_error": true, "result": text, "stop_reason": "stop_sequence",
+            "terminal_reason": "api_error", "origin": { "kind": "human" }, "user_message_uuids": [uuid],
+        }))
+    };
+    // As Claude Code sends it, and with the turn's end ahead of its result.
+    for lifecycle_first in [false, true] {
+        let mut process = load_fixture("simple").remove(0);
+        process.truncate(6);
+        let Some(Frame::Shim(prompt)) = process.last() else { panic!("the fixture's prompt") };
+        let uuid = prompt["uuid"].as_str().unwrap().to_owned();
+        process.push(Frame::Cli(json!({
+            "type": "assistant", "error": "authentication_failed", "parent_tool_use_id": null,
+            "message": { "id": "m", "model": "<synthetic>", "content": [{ "type": "text", "text": text }] },
+        })));
+        if lifecycle_first {
+            process.extend([lifecycle(&uuid, "cancelled"), result(&uuid)]);
+        } else {
+            process.extend([result(&uuid), lifecycle(&uuid, "cancelled")]);
+        }
+        let cli = Arc::new(Replay {
+            processes: Mutex::new(VecDeque::from([process])),
+            sent: Arc::default(),
+            launched: Mutex::default(),
+            errors: Arc::default(),
+        });
+        let (dir, cwd) = (tempfile::tempdir().unwrap(), tempfile::tempdir().unwrap());
+        let h =
+            Harness::connect(cli.clone(), dir.path().into(), dir.path().join("p"), cwd.path().into(), Vec::new()).await;
+        let s = h.new_session().await;
+        let Err(RpcError::Server { message, .. }) = h.prompt(&s, "hi").await else {
+            panic!("the turn should fail (lifecycle first: {lifecycle_first})");
+        };
+        assert_eq!(message, format!("Claude Code authentication failed: {text}"));
+    }
+}
+
 /// Fork and undo against the real CLI, across connections, in a symlinked directory
 /// (macOS `/tmp`).
 #[tokio::test(flavor = "multi_thread")]
@@ -829,6 +873,7 @@ fn which_result_ends_a_turn() {
    assert!(!belongs(&t, &json!({"user_message_uuids": ["a"]})), "a steer superseded it");
    assert!(belongs(&t, &json!({"subtype": "error_during_execution"})), "names no message");
    assert!(!belongs(&t, &json!({"origin": {"kind": "task-notification"}})), "Claude Code's own turn");
+    assert!(belongs(&t, &json!({"origin": {"kind": "human"}, "user_message_uuids": ["b"]})), "the prompt's own result");
    assert!(belongs(&turn(&["a", "b"], true), &json!({"user_message_uuids": ["a"]})));
 }

@@ -21,18 +21,27 @@ use std::sync::Arc;
 /// The newest install of `command` on the `PATH` a child sees, by its `--version`.
 /// Several installs are common (npm, Homebrew, the vendor's own installer), and the first
 /// on `PATH` is often an old one that the service no longer serves the current models to.
-/// A path, or a name found once (or not at all), is used as it is.
+/// A path, or a name not found on `PATH`, is used as it is; a single match returns its
+/// resolved path so Windows `PATHEXT` shims (`claude.cmd`, `codex.cmd`) start.
 pub(crate) fn newest_install(command: &str) -> String {
-    if Path::new(command).components().count() > 1 {
+    let path = ide_core::process::host_var_os("PATH")
+        .or_else(|| ide_core::process::shell_env().find(|(k, _)| *k == "PATH").map(|(_, v)| v.to_owned()))
+        .unwrap_or_default();
+    // Windows: read afresh, so a tool the user installed since the IDE started is found too.
+    newest_install_in(command, &ide_core::process::with_user_path(&path))
+}
+
+fn newest_install_in(command: &str, search: &std::ffi::OsStr) -> String {
+    if Path::new(command).components().count() > 1 || Path::new(command).is_absolute() {
        return command.to_owned();
    }
-    let path = ide_core::process::host_var_os("PATH")
-        .or_else(|| ide_core::process::shell_env().find(|(k, _)| *k == "PATH").map(|(_, v)| v.to_owned()));
+    let pathext = ide_core::process::host_var_os("PATHEXT");
+    let names =
+        ide_core::process::executable_names(command, cfg!(windows), pathext.as_deref().and_then(|p| p.to_str()));
    let mut seen = Vec::new();
-    let candidates: Vec<PathBuf> = path
-        .iter()
-        .flat_map(std::env::split_paths)
-        .map(|dir| dir.join(command))
+    let candidates: Vec<PathBuf> = std::env::split_paths(search)
+        .filter(|d| !d.as_os_str().is_empty())
+        .flat_map(|dir| names.iter().map(move |n| dir.join(n)))
        .filter(|p| p.is_file())
        .filter(|p| {
            let real = dunce::canonicalize(p).unwrap_or_else(|_| p.clone());
@@ -42,7 +51,7 @@ pub(crate) fn newest_install(command: &str) -> String {
        })
        .collect();
    if candidates.len() < 2 {
-        return command.to_owned();
+        return candidates.into_iter().next().map_or_else(|| command.to_owned(), |p| p.to_string_lossy().into_owned());
    }
    candidates
        .into_iter()
@@ -56,7 +65,7 @@ fn version_of(program: &Path) -> Option<Vec<u64>> {
    let mut cmd = std::process::Command::new(program);
    ide_core::process::prepare(&mut cmd);
    let out = cmd.arg("--version").envs(ide_core::process::shell_env()).output().ok()?;
-    parse_version(&String::from_utf8_lossy(&out.stdout))
+    parse_version(&ide_core::output_encoding::decode_tool_output(&out.stdout))
 }

 fn parse_version(text: &str) -> Option<Vec<u64>> {
@@ -66,16 +75,6 @@ fn parse_version(text: &str) -> Option<Vec<u64>> {
    })
 }

-#[cfg(test)]
-#[test]
-fn versions_are_read_from_either_side_of_the_name() {
-    assert_eq!(parse_version("codex-cli 0.164.0\n"), Some(vec![0, 164, 0]));
-    assert_eq!(parse_version("2.1.312 (Claude Code)"), Some(vec![2, 1, 312]));
-    assert_eq!(parse_version("v1.2"), Some(vec![1, 2]));
-    assert_eq!(parse_version("no version here"), None);
-    assert!(parse_version("codex-cli 0.164.0") > parse_version("codex-cli 0.147.0"));
-}
-
 /// The agent side of an in-process ACP connection.
 pub(crate) trait Shim: Handler {
    /// Called once, before any message arrives: the connection to the client, for
@@ -94,3 +93,56 @@ pub(crate) fn serve<S: Shim>(shim: Arc<S>, client: Arc<dyn Handler>) -> Peer {
    shim.attach(to_client);
    Peer::connect_framed(or, ow, client, Framing::Lines)
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn versions_are_read_from_either_side_of_the_name() {
+        assert_eq!(parse_version("codex-cli 0.164.0\n"), Some(vec![0, 164, 0]));
+        assert_eq!(parse_version("2.1.312 (Claude Code)"), Some(vec![2, 1, 312]));
+        assert_eq!(parse_version("v1.2"), Some(vec![1, 2]));
+        assert_eq!(parse_version("no version here"), None);
+        assert!(parse_version("codex-cli 0.164.0") > parse_version("codex-cli 0.147.0"));
+    }
+
+    #[test]
+    fn newest_install_resolves_single_candidate_and_keeps_missing_or_paths() {
+        let dir = tempfile::tempdir().unwrap();
+        let a = dir.path().join("a");
+        let b = dir.path().join("b");
+        std::fs::create_dir_all(&a).unwrap();
+        std::fs::create_dir_all(&b).unwrap();
+        std::fs::write(a.join("claude"), "#!/bin/sh\n").unwrap();
+        std::fs::write(b.join("claude.cmd"), "@echo off\n").unwrap();
+        let search = std::env::join_paths([&a, &b]).unwrap();
+        if cfg!(windows) {
+            assert_eq!(newest_install_in("claude", &search), b.join("claude.cmd").to_string_lossy());
+        } else {
+            assert_eq!(newest_install_in("claude", &search), a.join("claude").to_string_lossy());
+        }
+        assert_eq!(newest_install_in("nope", &search), "nope");
+        assert_eq!(newest_install_in("bin/claude", &search), "bin/claude");
+    }
+
+    #[cfg(unix)]
+    #[test]
+    fn newest_install_compares_versions_across_path_entries() {
+        use std::os::unix::fs::PermissionsExt;
+
+        let dir = tempfile::tempdir().unwrap();
+        let old = dir.path().join("old");
+        let new = dir.path().join("new");
+        for (path, version) in [(&old, "2.9.0"), (&new, "2.10.0")] {
+            std::fs::create_dir_all(path).unwrap();
+            let executable = path.join("agent");
+            std::fs::write(&executable, format!("#!/bin/sh\necho {version}\n")).unwrap();
+            std::fs::set_permissions(&executable, std::fs::Permissions::from_mode(0o755)).unwrap();
+        }
+        for paths in [[&old, &new], [&new, &old]] {
+            let search = std::env::join_paths(paths).unwrap();
+            assert_eq!(newest_install_in("agent", &search), new.join("agent").to_string_lossy());
+        }
+    }
+}
@@ -222,6 +222,13 @@ fn choose<'a>(entry: &'a Entry, platform: Platform, on_path: &dyn Fn(&str) -> bo
    {
        return Some(Choice::Uvx(p));
    }
+    // Last resort: npx and uvx run natively, this one under OS emulation.
+    if platform.os == Os::Windows
+        && platform.arch == Arch::Arm64
+        && let Some(b) = d.binary.get("windows-x86_64")
+    {
+        return Some(Choice::Binary(b));
+    }
    None
 }

@@ -335,7 +342,7 @@ pub fn mark_updates(paths: &RegistryPaths, providers: &mut [AgentProvider]) {

 /// HTTPS only, redirects included. Tests serve downloads over `file://`.
 fn http() -> IdeResult<Http> {
-    let http = Http::new(&ide_tools::default_search_path())?;
+    let http = Http::new(&ide_core::tool_path::search_path())?;
    Ok(if cfg!(test) { http } else { http.https_only() })
 }

@@ -689,6 +696,20 @@ mod tests {
    const LINUX: Platform = Platform { os: Os::Linux, arch: Arch::X64 };
    const WINDOWS: Platform = Platform { os: Os::Windows, arch: Arch::X64 };

+    #[test]
+    fn windows_arm_binary_prefers_native_then_x64() {
+        let mut entry = parse(INDEX).unwrap().remove(0);
+        let arm = Platform { os: Os::Windows, arch: Arch::Arm64 };
+        assert!(matches!(choose(&entry, arm, &|_| false), Some(Choice::Binary(_))));
+        assert!(choose(&entry, Platform { os: Os::Linux, arch: Arch::Arm64 }, &|_| false).is_none());
+        entry.distribution.npx = Some(serde_json::from_str(r#"{"package":"amp-acp"}"#).unwrap());
+        assert!(matches!(choose(&entry, arm, &|_| true), Some(Choice::Npx(_))));
+        let mut native = entry.distribution.binary["windows-x86_64"].clone();
+        native.cmd = "native.exe".into();
+        entry.distribution.binary.insert("windows-aarch64".into(), native);
+        assert!(matches!(choose(&entry, arm, &|_| false), Some(Choice::Binary(b)) if b.cmd == "native.exe"));
+    }
+
    const INDEX: &str = r#"{"version":"1.0.0","agents":[
        {"id":"amp-acp","name":"Amp","version":"0.10.0","description":"Amp over ACP",
         "repository":"https://github.com/x/amp-acp","authors":["x"],"license":"Apache-2.0",
@@ -185,7 +185,23 @@ pub(crate) fn recorder(out: PathBuf) -> Connector {
    let file = Arc::new(Mutex::new(String::new()));
    let connections = Arc::new(Mutex::new(0u32));
    Arc::new(move |spec, cwd, client, on_stderr| {
-        let mut cmd = tokio::process::Command::new(&spec.command);
+        let program = {
+            let path = Path::new(&spec.command);
+            if path.components().count() > 1 || path.is_absolute() {
+                path.to_path_buf()
+            } else {
+                let search = spec
+                    .env
+                    .iter()
+                    .find(|(k, _)| k.eq_ignore_ascii_case("PATH"))
+                    .map(|(_, v)| std::ffi::OsString::from(v))
+                    .or_else(|| ide_core::process::shell_env().find(|(k, _)| k == "PATH").map(|(_, v)| v))
+                    .or_else(|| ide_core::process::host_var_os("PATH"))
+                    .unwrap_or_default();
+                ide_core::process::find_executable(&spec.command, &search).unwrap_or_else(|| path.to_path_buf())
+            }
+        };
+        let mut cmd = tokio::process::Command::new(&program);
        ide_core::process::prepare(cmd.as_std_mut());
        let mut child = cmd
            .args(&spec.args)
@@ -56,6 +56,7 @@ fn config(provider: &str) -> Vec<AgentConfigChoice> {

 async fn create(mgr: &AgentManager, provider: &str, prompt: &str) -> String {
    let req = NewAgentTask {
+        project_root: None,
        prompt: text(prompt),
        provider: provider.into(),
        config: config(provider),
@@ -210,10 +210,11 @@ async fn commands_are_remembered_per_project_and_merged_with_skills_on_disk() {
    let names = |c: Vec<AgentCommand>| c.into_iter().map(|c| c.name).collect::<Vec<_>>();

    let mgr_a = manager_at(&a, &models, Arc::new(FakeAgent::default()));
-    // Before any session: the skills on disk.
+    // Before any session: only the skills on disk.
    assert_eq!(names(mgr_a.commands("claude", None).await.unwrap()), ["triage"]);
    let task = mgr_a
        .create(NewAgentTask {
+            project_root: None,
            prompt: text("Fix the lexer"),
            provider: "claude".into(),
            config: Vec::new(),
@@ -227,6 +228,8 @@ async fn commands_are_remembered_per_project_and_merged_with_skills_on_disk() {
    assert_eq!(names(mgr_a.commands("claude", Some(&task.id)).await.unwrap()), ["review", "triage"]);
    // Other agents get only what they offered.
    assert!(mgr_a.commands("codex", None).await.unwrap().is_empty());
+    mgr_a.cancel(&task.id, None).unwrap();
+    wait_for(&mgr_a, &task.id, AgentStatus::Ready).await;
    mgr_a.shutdown();

    // Another project shares the settings but not the commands.
@@ -239,6 +242,46 @@ async fn commands_are_remembered_per_project_and_merged_with_skills_on_disk() {
    assert_eq!(names(mgr_a.providers().into_iter().find(|p| p.id == "claude").unwrap().commands), ["review"]);
 }

+#[tokio::test(flavor = "multi_thread")]
+async fn builtin_commands_only_fill_verified_gaps_and_preserve_advertised_metadata() {
+    let tmp = tempfile::tempdir().unwrap();
+    let agent = Arc::new(FakeAgent::default());
+    let mgr = manager_at(tmp.path(), &tmp.path().join("models.json"), agent);
+    for provider in ["claude", "claude-acp", "opencode2", "codex", "custom"] {
+        assert!(mgr.commands(provider, None).await.unwrap().is_empty(), "{provider}");
+    }
+    let commands = mgr.commands("opencode", None).await.unwrap();
+    assert_eq!(commands.iter().map(|c| c.name.as_str()).collect::<Vec<_>>(), ["compact"]);
+    let task = mgr
+        .create(NewAgentTask {
+            project_root: None,
+            prompt: text("Hello"),
+            provider: "opencode".into(),
+            config: Vec::new(),
+            isolation: Isolation::Local,
+            base: None,
+        })
+        .await
+        .unwrap();
+    wait_for(&mgr, &task.id, AgentStatus::NeedsInput).await;
+    let advertised = AgentCommand {
+        name: "compact".into(),
+        description: "Agent supplied description".into(),
+        hint: Some("instructions".into()),
+    };
+    mgr.task(&task.id).unwrap().state.lock().task.commands = vec![advertised.clone()];
+    // The task's provider wins over the caller's provider; metadata is not replaced.
+    let commands = mgr.commands("claude", Some(&task.id)).await.unwrap();
+    assert_eq!(commands.len(), 1);
+    assert_eq!(commands[0].name, advertised.name);
+    assert_eq!(commands[0].description, advertised.description);
+    assert_eq!(commands[0].hint, advertised.hint);
+    // Finish the in-process agent before Tokio stops driving its permission response.
+    mgr.cancel(&task.id, None).unwrap();
+    wait_for(&mgr, &task.id, AgentStatus::Ready).await;
+    mgr.shutdown();
+}
+
 async fn wait_for(mgr: &AgentManager, id: &str, status: AgentStatus) {
    for _ in 0..500 {
        let task = mgr.task(id).unwrap();
@@ -268,6 +311,7 @@ async fn a_task_runs_asks_for_permission_and_survives_a_restart() {

    let task = mgr
        .create(NewAgentTask {
+            project_root: None,
            prompt: text("Fix the lexer\nmore detail"),
            provider: "claude".into(),
            config: vec![AgentConfigChoice { id: "model".into(), value: "small".into() }],
@@ -374,6 +418,7 @@ async fn messages_sent_while_busy_are_queued_and_send_now_interrupts() {
    let mgr = manager(tmp.path(), agent.clone());
    let task = mgr
        .create(NewAgentTask {
+            project_root: None,
            prompt: text("wait"),
            provider: "claude".into(),
            config: vec![],
@@ -428,6 +473,7 @@ async fn subagents_get_their_own_conversation() {
    let mgr = manager(tmp.path(), agent.clone());
    let task = mgr
        .create(NewAgentTask {
+            project_root: None,
            prompt: text("delegate"),
            provider: "claude".into(),
            config: vec![],
@@ -521,6 +567,7 @@ async fn cancelling_resolves_the_open_permission_and_delete_forgets_the_task() {
    let mgr = manager(tmp.path(), Arc::new(FakeAgent::default()));
    let task = mgr
        .create(NewAgentTask {
+            project_root: None,
            prompt: text("do it"),
            provider: "codex".into(),
            config: vec![],
@@ -542,6 +589,7 @@ async fn cancelling_resolves_the_open_permission_and_delete_forgets_the_task() {
    assert!(!tmp.path().join("store").join(format!("{}.json", task.id)).exists());
    assert!(
        mgr.create(NewAgentTask {
+            project_root: None,
            prompt: text(" "),
            provider: "codex".into(),
            config: vec![],
@@ -587,6 +635,7 @@ async fn real_claude_task_in_a_worktree() {
    );
    let task = mgr
        .create(NewAgentTask {
+            project_root: None,
            prompt: text("Create a file named hello.txt containing the single word hi. Do nothing else."),
            provider: "claude".into(),
            config: vec![AgentConfigChoice { id: "model".into(), value: "haiku".into() }],
@@ -635,6 +684,7 @@ async fn forks_rollbacks_and_steering() {
    let agent = Arc::new(FakeAgent::default());
    let mgr = manager(tmp.path(), agent.clone());
    let new = |prompt: &str| NewAgentTask {
+        project_root: None,
        prompt: text(prompt),
        provider: "claude".into(),
        config: Vec::new(),
@@ -685,6 +735,7 @@ async fn usage_limits_and_late_settings() {
    let mgr = manager(tmp.path(), agent.clone());
    let task = mgr
        .create(NewAgentTask {
+            project_root: None,
            prompt: text("limit"),
            provider: "claude".into(),
            // `effort` isn't offered until the session runs.
@@ -727,6 +778,7 @@ async fn cursor_approval_switch_resolves_pending_and_survives_restart() {
    let agent = Arc::new(FakeAgent::default());
    let mgr = manager(tmp.path(), agent.clone());
    let new = || NewAgentTask {
+        project_root: None,
        prompt: text("Fix"),
        provider: "cursor".into(),
        config: Vec::new(),
@@ -752,15 +804,17 @@ async fn cursor_approval_switch_resolves_pending_and_survives_restart() {
    mgr.prompt(&task.id, text("Fix again"), false).await.unwrap();
    wait_for(&mgr, &task.id, AgentStatus::Ready).await;
    assert!(!agent.calls.lock().iter().any(|c| c.contains("bypass")));
-    assert!(!config::bypass_approvals("cursor", &mgr.shared.known_config("cursor")));
+    assert!(config::bypass_approvals("cursor", &mgr.shared.known_config("cursor")));
    mgr.set_config(&task.id, config::CURSOR_APPROVAL, "ask".into()).await.unwrap();
    mgr.prompt(&task.id, text("Fix once more"), false).await.unwrap();
    wait_for(&mgr, &task.id, AgentStatus::NeedsInput).await;
    mgr.cancel(&task.id, None).unwrap();
    wait_for(&mgr, &task.id, AgentStatus::Ready).await;
-    // An unrelated new conversation still asks, even after the cache was updated.
+    // A task created without choosing approvals still asks; the New Task page sends the default.
    let other = mgr.create(new()).await.unwrap();
    wait_for(&mgr, &other.id, AgentStatus::NeedsInput).await;
+    mgr.cancel(&other.id, None).unwrap();
+    wait_for(&mgr, &other.id, AgentStatus::Ready).await;
    mgr.shutdown();
 }

@@ -770,6 +824,7 @@ async fn cursor_approval_choice_applies_before_first_prompt() {
    let mgr = manager(tmp.path(), Arc::new(FakeAgent::default()));
    let task = mgr
        .create(NewAgentTask {
+            project_root: None,
            prompt: text("Fix"),
            provider: "cursor".into(),
            config: vec![AgentConfigChoice { id: config::CURSOR_APPROVAL.into(), value: "bypass".into() }],
@@ -781,3 +836,109 @@ async fn cursor_approval_choice_applies_before_first_prompt() {
    wait_for(&mgr, &task.id, AgentStatus::Ready).await;
    mgr.shutdown();
 }
+
+#[tokio::test(flavor = "multi_thread")]
+async fn archived_tasks_can_be_restored_and_continue_their_session() {
+    let tmp = tempfile::tempdir().unwrap();
+    let agent = Arc::new(FakeAgent::default());
+    let mgr = manager(tmp.path(), agent.clone());
+    let task = mgr
+        .create(NewAgentTask {
+            project_root: None,
+            prompt: text("again"),
+            provider: "claude".into(),
+            config: vec![],
+            isolation: Isolation::Local,
+            base: None,
+        })
+        .await
+        .unwrap();
+    wait_for(&mgr, &task.id, AgentStatus::Ready).await;
+    let entries = mgr.entries(&task.id, None).unwrap();
+    mgr.archive(&task.id).unwrap();
+    assert!(mgr.prompt(&task.id, text("again"), false).await.is_err());
+    mgr.unarchive(&task.id).unwrap();
+    assert_eq!(mgr.task(&task.id).unwrap().state.lock().task.status, AgentStatus::Ready);
+    assert!(mgr.task(&task.id).unwrap().live.lock().is_none());
+    assert_eq!(mgr.entries(&task.id, None).unwrap().len(), entries.len());
+    drop(mgr);
+    let mgr = manager(tmp.path(), agent.clone());
+    assert_eq!(mgr.task(&task.id).unwrap().state.lock().task.status, AgentStatus::Ready);
+    mgr.prompt(&task.id, text("again"), false).await.unwrap();
+    wait_for(&mgr, &task.id, AgentStatus::Ready).await;
+    assert!(agent.calls.lock().iter().any(|call| call == "session/load"));
+    assert_eq!(mgr.entries(&task.id, None).unwrap().len(), entries.len() + 2);
+    mgr.unarchive(&task.id).unwrap();
+}
+
+#[tokio::test(flavor = "multi_thread")]
+async fn task_project_root_controls_local_and_worktree_repositories() {
+    let tmp = tempfile::tempdir().unwrap();
+    let root = dunce::canonicalize(tmp.path()).unwrap();
+    let member = root.join("project-b");
+    std::fs::create_dir(&member).unwrap();
+    let git = |args: &[&str]| {
+        let out = std::process::Command::new("git")
+            .args(["-c", "user.name=t", "-c", "user.email=t@t", "-c", "commit.gpgsign=false"])
+            .args(args)
+            .current_dir(&member)
+            .output()
+            .unwrap();
+        assert!(out.status.success(), "{}", String::from_utf8_lossy(&out.stderr));
+        String::from_utf8_lossy(&out.stdout).trim().to_owned()
+    };
+    git(&["init", "-q", "-b", "member-main"]);
+    std::fs::write(member.join("file.txt"), "original\n").unwrap();
+    git(&["add", "."]);
+    git(&["commit", "-qm", "initial"]);
+    let mgr = manager(&root, Arc::new(FakeAgent::default()));
+    for isolation in [Isolation::Local, Isolation::Worktree] {
+        let task = mgr
+            .create(NewAgentTask {
+                project_root: Some(IpcPath(member.clone())),
+                prompt: text("member task"),
+                provider: "claude".into(),
+                config: vec![],
+                isolation,
+                base: None,
+            })
+            .await
+            .unwrap();
+        wait_for(&mgr, &task.id, AgentStatus::NeedsInput).await;
+        let permission = mgr
+            .entries(&task.id, None)
+            .unwrap()
+            .iter()
+            .find_map(|e| match e {
+                AgentEntry::Permission { id, .. } => Some(*id),
+                _ => None,
+            })
+            .unwrap();
+        mgr.respond(&task.id, permission, Some("yes".into())).unwrap();
+        wait_for(&mgr, &task.id, AgentStatus::Ready).await;
+        assert_eq!(task.project_root, Some(IpcPath(member.clone())));
+        assert_eq!(task.base.as_deref(), Some("member-main"));
+        if isolation == Isolation::Local {
+            assert_eq!(task.cwd.0, member);
+        } else {
+            assert_ne!(task.cwd.0, member);
+            assert_eq!(std::fs::read_to_string(task.cwd.0.join("file.txt")).unwrap(), "original\n");
+        }
+        std::fs::write(task.cwd.0.join("file.txt"), "changed\n").unwrap();
+        let changes = mgr.changes(&task.id).await.unwrap();
+        assert_eq!(changes.len(), 1);
+        assert_eq!(changes[0].path.0, task.cwd.0.join("file.txt"));
+        assert_eq!(mgr.base_text(&task.id, changes[0].path.0.clone()).await.unwrap().as_deref(), Some("original\n"));
+        let saved = std::fs::read(root.join("store").join(format!("{}.json", task.id))).unwrap();
+        assert!(String::from_utf8(saved).unwrap().contains("projectRoot"));
+        let mut old = serde_json::to_value(&task).unwrap();
+        old.as_object_mut().unwrap().remove("projectRoot");
+        assert!(serde_json::from_value::<AgentTask>(old).unwrap().project_root.is_none());
+        mgr.delete(&task.id, true).await.unwrap();
+        if isolation == Isolation::Worktree {
+            assert!(!task.cwd.0.exists());
+        }
+        std::fs::write(member.join("file.txt"), "original\n").unwrap();
+    }
+    assert_eq!(git(&["worktree", "list", "--porcelain"]).matches("worktree ").count(), 1);
+}
@@ -446,6 +446,7 @@ mod tests {
        let user = |sent: f64| AgentEntry::User {
            text: "q".into(),
            attachments: vec![],
+            images: vec![],
            sent_ms: Some(sent),
            done_ms: None,
            steered: false,
@@ -53,8 +53,9 @@ pub(crate) fn remove(project_root: &Path, path: &Path) -> IdeResult<()> {
 }

 /// Files under `cwd` that differ from `base` (untracked files included), with line counts.
+/// Outside a repository there is nothing to compare against: no changes.
 pub(crate) fn changes(cwd: &Path, base: &str) -> IdeResult<Vec<AgentChange>> {
-    let repo = repo_at(cwd)?;
+    let Some(repo) = Repo::discover(cwd)? else { return Ok(Vec::new()) };
    let root = repo.root().to_path_buf();
    let stats = repo.numstat_with_worktree(base)?;
    let stat = |rel: &str| stats.iter().find(|(p, ..)| p == rel).map_or((0, 0), |&(_, a, r)| (a, r));
@@ -96,7 +97,12 @@ pub(crate) fn without_untouched(changes: Vec<AgentChange>, before: &BTreeMap<Str
 }

 pub(crate) fn file_at(cwd: &Path, path: &Path, rev: &str) -> IdeResult<Option<String>> {
-    repo_at(cwd)?.file_at(path, Some(rev))
+    let Some(repo) = Repo::discover(cwd)? else { return Ok(None) };
+    let encoding = match ide_vfs::load_text(path) {
+        Ok(loaded) => encoding_rs::Encoding::for_label(loaded.encoding.as_bytes()).unwrap_or(encoding_rs::UTF_8),
+        Err(_) => ide_vfs::detect_encoding(&repo.file_bytes_at(path, Some(rev))?.unwrap_or_default(), None),
+    };
+    repo.file_at(path, Some(rev), encoding)
 }

 /// A short ASCII branch-safe name from the task title.
@@ -136,6 +142,20 @@ mod tests {
        assert_eq!(unique_slug("x", |s| s == "x" || s == "x-2"), "x-3");
    }

+    #[test]
+    fn outside_a_repository_there_is_nothing_to_compare() {
+        let tmp = tempfile::tempdir().unwrap();
+        let dir = tmp.path().join("plain");
+        std::fs::create_dir(&dir).unwrap();
+        std::fs::write(dir.join("a.txt"), "one\n").unwrap();
+
+        assert!(changes(&dir, "HEAD").unwrap().is_empty());
+        assert!(snapshot(&dir).unwrap().is_empty());
+        assert_eq!(file_at(&dir, &dir.join("a.txt"), "HEAD").unwrap(), None);
+        assert!(create(&dir, &tmp.path().join("wt"), "Edit A", None).is_err());
+        assert!(remove(&dir, &dir).is_err());
+    }
+
    fn git(dir: &Path, args: &[&str]) {
        let ok = std::process::Command::new("git")
            .args(["-c", "user.name=t", "-c", "user.email=t@t", "-c", "commit.gpgsign=false"])
@@ -0,0 +1,218 @@
+//! Resource processing by the project's build tool, then publishing to the live JVM's output directory.
+use crate::BuildModel;
+use ide_core::{IdeError, IdeResult};
+use std::collections::BTreeMap;
+use std::fs;
+use std::path::{Path, PathBuf};
+
+pub struct ResourceBuild {
+    pub command: String,
+    pub args: Vec<String>,
+    pub cwd: String,
+    pub env: BTreeMap<String, String>,
+    pub kind: &'static str,
+}
+
+fn literal(value: &str) -> String {
+    format!("'{}'", value.replace('\\', "\\\\").replace('\'', "\\'"))
+}
+
+pub fn plan(root: &Path, model: &BuildModel, module: &Path, cache: &Path) -> IdeResult<ResourceBuild> {
+    fs::create_dir_all(cache)?;
+    let manifest = cache.join("resource-output.txt");
+    if manifest.exists() {
+        fs::remove_file(&manifest)?;
+    }
+    let module = dunce::canonicalize(root.join(module))?;
+    if let Some(p) = model.maven.as_ref().and_then(|m| m.projects.iter().find(|p| root.join(&p.dir) == module)) {
+        let mut args = p.options.clone();
+        args.extend([
+            "process-resources".into(),
+            "help:evaluate".into(),
+            "-Dexpression=project.build.outputDirectory".into(),
+            format!("-Doutput={}", manifest.display()),
+        ]);
+        return Ok(ResourceBuild {
+            command: p.command.clone(),
+            args,
+            cwd: p.dir.clone(),
+            env: p.env.clone(),
+            kind: "maven",
+        });
+    }
+    if let Some(g) = &model.gradle
+        && let Some(p) = g.projects.iter().find(|p| root.join(&p.dir) == module)
+    {
+        let script = cache.join("resources.init.gradle");
+        fs::write(
+            &script,
+            format!(
+                r#"gradle.projectsEvaluated {{
+    def p = gradle.rootProject.project({})
+    def resources = p.tasks.named('processResources')
+    p.tasks.register('openideaUpdateResources') {{
+        dependsOn resources
+        doLast {{ new File({}).setText(resources.get().destinationDir.absolutePath, 'UTF-8') }}
+    }}
+}}
+"#,
+                literal(&p.path),
+                literal(&manifest.to_string_lossy())
+            ),
+        )?;
+        return Ok(ResourceBuild {
+            command: g.command.clone(),
+            args: vec![
+                "--init-script".into(),
+                script.to_string_lossy().into_owned(),
+                format!("{}:openideaUpdateResources", p.path.trim_end_matches(':')),
+            ],
+            cwd: g.dir.clone(),
+            env: g.env.clone(),
+            kind: "gradle",
+        });
+    }
+    Err(IdeError::invalid("The Spring Boot module must belong to a linked Maven or Gradle build"))
+}
+
+pub fn publish(root: &Path, cache: &Path, class_paths: &[String], main_class: &str) -> IdeResult<()> {
+    let output = PathBuf::from(fs::read_to_string(cache.join("resource-output.txt"))?.trim());
+    if !output.is_absolute() || !output.is_dir() {
+        return Err(IdeError::invalid("The resource build did not report an output directory"));
+    }
+    let output = dunce::canonicalize(output)?;
+    let paths: Vec<_> = class_paths.iter().filter_map(|p| dunce::canonicalize(root.join(p)).ok()).collect();
+    // A separate resource directory is already on the runtime classpath (e.g. build/resources/main).
+    if paths.contains(&output) {
+        return Ok(());
+    }
+    // jdtls uses bin/main for Gradle, rather than Gradle's build/resources/main.
+    let class_file = main_class.split('.').collect::<PathBuf>().with_extension("class");
+    let destination = paths.iter().find(|p| p.join(&class_file).is_file()).ok_or_else(|| {
+        IdeError::invalid("Cannot find the running main class output directory; restart the application")
+    })?;
+    let previous: Vec<String> = fs::read(cache.join("published-resources.json"))
+        .ok()
+        .and_then(|bytes| serde_json::from_slice(&bytes).ok())
+        .unwrap_or_default();
+    let mut current = Vec::new();
+    copy_resources(&output, &output, destination, &mut current)?;
+    for rel in previous.iter().filter(|p| !current.contains(p)) {
+        let path = destination.join(rel);
+        if path.is_file() {
+            fs::remove_file(path)?;
+        }
+    }
+    fs::write(
+        cache.join("published-resources.json"),
+        serde_json::to_vec(&current).map_err(|e| IdeError::internal(e.to_string()))?,
+    )?;
+    Ok(())
+}
+
+fn copy_resources(root: &Path, from: &Path, to: &Path, copied: &mut Vec<String>) -> IdeResult<()> {
+    for entry in fs::read_dir(from)? {
+        let entry = entry?;
+        let path = entry.path();
+        let kind = entry.file_type()?;
+        if kind.is_symlink() {
+            continue;
+        }
+        if kind.is_dir() {
+            copy_resources(root, &path, to, copied)?;
+        } else if kind.is_file() && path.extension().is_none_or(|e| e != "class") {
+            let rel = path.strip_prefix(root).map_err(|e| IdeError::internal(e.to_string()))?;
+            let dest = to.join(rel);
+            if let Some(parent) = dest.parent() {
+                fs::create_dir_all(parent)?;
+            }
+            fs::copy(&path, dest)?;
+            copied.push(rel.to_string_lossy().into_owned());
+        }
+    }
+    Ok(())
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn resource_plans_use_the_selected_module_and_build_configuration() {
+        let tmp = tempfile::tempdir().unwrap();
+        let root = dunce::canonicalize(tmp.path()).unwrap();
+        fs::create_dir(root.join("app")).unwrap();
+        let mut model = BuildModel {
+            maven: Some(crate::MavenModel {
+                projects: vec![crate::MavenProject {
+                    dir: "app".into(),
+                    command: "/tools/mvnw".into(),
+                    options: vec!["-Pdev".into()],
+                    env: BTreeMap::from([("JAVA_HOME".into(), "/jdk".into())]),
+                    ..Default::default()
+                }],
+                ..Default::default()
+            }),
+            ..Default::default()
+        };
+        let cache = root.join("cache");
+        let maven = plan(&root, &model, Path::new("app"), &cache).unwrap();
+        assert_eq!(maven.command, "/tools/mvnw");
+        assert_eq!(maven.cwd, "app");
+        assert_eq!(maven.args[0..2], ["-Pdev", "process-resources"]);
+        assert!(maven.args.contains(&"-Dexpression=project.build.outputDirectory".into()));
+        assert_eq!(maven.env["JAVA_HOME"], "/jdk");
+        model.maven = None;
+        model.gradle = Some(crate::GradleModel {
+            command: "/tools/gradlew".into(),
+            projects: vec![crate::GradleProject { path: ":app".into(), dir: "app".into(), ..Default::default() }],
+            ..Default::default()
+        });
+        let gradle = plan(&root, &model, Path::new("app"), &cache).unwrap();
+        assert_eq!(gradle.command, "/tools/gradlew");
+        assert_eq!(gradle.args.last().unwrap(), ":app:openideaUpdateResources");
+        let script = fs::read_to_string(cache.join("resources.init.gradle")).unwrap();
+        assert!(script.contains("processResources") && script.contains("destinationDir.absolutePath"));
+        assert!(!script.contains("build/resources/main")); // The task owns custom output locations.
+    }
+
+    #[test]
+    fn publishes_maven_and_gradle_resource_outputs_to_the_runtime_classpath() {
+        for layout in ["target/classes", "build/resources/main", "custom resource output"] {
+            let tmp = tempfile::tempdir().unwrap();
+            let root = tmp.path();
+            let cache = root.join("cache");
+            let output = root.join(layout);
+            let runtime = if layout == "target/classes" { output.clone() } else { root.join("bin/main") };
+            fs::create_dir_all(output.join("static")).unwrap();
+            fs::create_dir_all(runtime.join("example")).unwrap();
+            fs::create_dir_all(&cache).unwrap();
+            fs::write(cache.join("resource-output.txt"), output.to_string_lossy().as_bytes()).unwrap();
+            fs::write(output.join("static/index.html"), "after").unwrap();
+            fs::write(output.join("unrelated.class"), "do not publish").unwrap();
+            fs::write(runtime.join("example/Application.class"), "running").unwrap();
+            publish(root, &cache, &[runtime.to_string_lossy().into_owned()], "example.Application").unwrap();
+            assert_eq!(fs::read_to_string(runtime.join("static/index.html")).unwrap(), "after");
+            assert_eq!(fs::read_to_string(runtime.join("example/Application.class")).unwrap(), "running");
+            if output != runtime {
+                assert!(!runtime.join("unrelated.class").exists());
+                fs::remove_file(output.join("static/index.html")).unwrap();
+                publish(root, &cache, &[runtime.to_string_lossy().into_owned()], "example.Application").unwrap();
+                assert!(!runtime.join("static/index.html").exists());
+            }
+        }
+    }
+
+    #[test]
+    fn leaves_separate_runtime_resource_directories_in_place_and_rejects_jar_only_runs() {
+        let tmp = tempfile::tempdir().unwrap();
+        let root = tmp.path();
+        let output = root.join("build/resources/main");
+        let cache = root.join("cache");
+        fs::create_dir_all(&output).unwrap();
+        fs::create_dir(&cache).unwrap();
+        fs::write(cache.join("resource-output.txt"), output.to_string_lossy().as_bytes()).unwrap();
+        publish(root, &cache, &[output.to_string_lossy().into_owned()], "a.Main").unwrap();
+        assert!(publish(root, &cache, &["app.jar".into()], "a.Main").is_err());
+    }
+}
@@ -0,0 +1,321 @@
+//! Metadata fingerprints for successful Maven launch builds.
+use super::*;
+use std::fs;
+use std::hash::{Hash, Hasher};
+use std::time::SystemTime;
+
+#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
+pub struct LaunchFingerprint {
+    version: u32,
+    parameters: String,
+    files: BTreeMap<PathBuf, Option<(u64, SystemTime)>>,
+}
+
+fn scan(
+    path: &Path,
+    files: &mut BTreeMap<PathBuf, Option<(u64, SystemTime)>>,
+    ancestors: &mut HashSet<PathBuf>,
+    cancel: &CancellationToken,
+) -> IdeResult<()> {
+    if cancel.is_cancelled() {
+        return Err(IdeError::cancelled());
+    }
+    let meta = match fs::metadata(path) {
+        Ok(meta) => meta,
+        Err(e) if e.kind() == std::io::ErrorKind::NotFound => {
+            files.insert(path.to_path_buf(), None);
+            return Ok(());
+        }
+        Err(e) => return Err(e.into()),
+    };
+    if meta.is_dir() {
+        let canonical = dunce::canonicalize(path)?;
+        if !ancestors.insert(canonical.clone()) {
+            return Err(IdeError::internal("cyclic launch input directory"));
+        }
+        // Directory mtimes change on irrelevant JDT writes. File paths detect additions/deletions.
+        files.insert(path.to_path_buf(), None);
+        for entry in fs::read_dir(path)? {
+            scan(&entry?.path(), files, ancestors, cancel)?;
+        }
+        ancestors.remove(&canonical);
+    } else if meta.is_file() {
+        files.insert(path.to_path_buf(), Some((meta.len(), meta.modified()?)));
+    } else {
+        return Err(IdeError::internal("unsupported launch input file"));
+    }
+    Ok(())
+}
+
+/// `None` means an input cannot be resolved safely: build normally without reuse.
+/// All filesystem work belongs on the caller's blocking thread.
+pub fn launch_fingerprint(
+    root: &Path,
+    model: &BuildModel,
+    module: &Path,
+    test: bool,
+    local_repo: Option<PathBuf>,
+    cancel: &CancellationToken,
+) -> IdeResult<Option<LaunchFingerprint>> {
+    let Some(m) = &model.maven else { return Ok(None) };
+    let projects = maven_launch_projects(root, m, module, test);
+    if projects.is_empty() {
+        return Ok(None);
+    }
+    let Some(mut inputs) = maven::launch_inputs(root, &projects, local_repo) else { return Ok(None) };
+    let plan = launch_plan(root, model, module, test)?;
+    let mut environment: BTreeMap<String, String> = std::env::vars()
+        .map(|(key, value)| (key.to_ascii_uppercase(), value))
+        .filter(|(key, _)| {
+            key.starts_with("MAVEN_")
+                || key.starts_with("JAVA_")
+                || key.starts_with("JDK_")
+                || matches!(
+                    key.as_str(),
+                    "PATH" | "HOME" | "LANG" | "LC_ALL" | "_JAVA_OPTIONS" | "M2_HOME" | "MAVEN_HOME"
+                )
+        })
+        .collect();
+    // Explicit step values override the inherited environment just as they do in Command.
+    for step in &plan.steps {
+        environment.extend(step.env.iter().map(|(key, value)| (key.to_ascii_uppercase(), value.clone())));
+        for dir in step.cwd.ancestors() {
+            inputs.extend([dir.join(".mvn"), dir.join("mvnw"), dir.join("mvnw.cmd")]);
+            if dir == root {
+                break;
+            }
+        }
+        let program = process::program_path(&step.program, &step.env);
+        inputs.push(program.clone());
+        // Maven installed via a symlink still reads conf from its distribution.
+        if let Ok(program) = dunce::canonicalize(program)
+            && let Some(home) = program.parent().and_then(Path::parent)
+        {
+            for conf in ["conf", "libexec/conf"] {
+                inputs.extend([home.join(conf).join("settings.xml"), home.join(conf).join("toolchains.xml")]);
+            }
+        }
+        if !environment.contains_key("JAVA_HOME") {
+            let java = process::program_path(if cfg!(windows) { "java.exe" } else { "java" }, &step.env);
+            inputs.push(java.clone());
+            if let Ok(java) = dunce::canonicalize(java)
+                && let Some(home) = java.parent().and_then(Path::parent)
+            {
+                inputs.push(home.join("release"));
+            }
+        }
+        for (i, arg) in step.args.iter().enumerate() {
+            if matches!(arg.as_str(), "-s" | "--settings" | "-gs" | "--global-settings" | "-t" | "--toolchains")
+                && let Some(file) = step.args.get(i + 1)
+            {
+                inputs.push(step.cwd.join(file));
+            }
+            for prefix in ["--settings=", "--global-settings=", "--toolchains="] {
+                if let Some(file) = arg.strip_prefix(prefix) {
+                    inputs.push(step.cwd.join(file));
+                }
+            }
+        }
+    }
+    if let Some(home) = dirs::home_dir() {
+        inputs.extend([home.join(".m2/settings.xml"), home.join(".m2/toolchains.xml")]);
+    }
+    for key in ["MAVEN_HOME", "M2_HOME"] {
+        if let Some(home) = environment.get(key) {
+            inputs.extend([Path::new(home).join("conf/settings.xml"), Path::new(home).join("conf/toolchains.xml")]);
+        }
+    }
+    if let Some(home) = environment.get("JAVA_HOME") {
+        inputs.extend([
+            Path::new(home).join("release"),
+            Path::new(home).join("lib/modules"),
+            Path::new(home).join("lib/tools.jar"),
+            Path::new(home).join(if cfg!(windows) { "bin/java.exe" } else { "bin/java" }),
+        ]);
+    }
+    let steps: Vec<_> =
+        plan.steps.iter().map(|s| (process::program_path(&s.program, &s.env), &s.args, &s.cwd, &s.env)).collect();
+    // Profiles and plugins can read arbitrary environment variables. Keep a signature
+    // of the inherited environment without persisting unrelated credentials.
+    let inherited: BTreeMap<_, _> = std::env::vars_os().collect();
+    let mut inherited_hash = std::hash::DefaultHasher::new();
+    inherited.hash(&mut inherited_hash);
+    let parameters =
+        serde_json::to_string(&(root, module, test, steps, environment, inherited_hash.finish(), projects))
+            .map_err(|e| IdeError::internal(e.to_string()))?;
+    let mut files = BTreeMap::new();
+    for path in inputs {
+        scan(&path, &mut files, &mut HashSet::new(), cancel)?;
+    }
+    // Store project inputs relative to the project, including each file's relative path.
+    let files = files.into_iter().map(|(p, stamp)| (p.strip_prefix(root).unwrap_or(&p).to_path_buf(), stamp)).collect();
+    Ok(Some(LaunchFingerprint { version: 1, parameters, files }))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn write(root: &Path, rel: &str, value: &str) {
+        let path = root.join(rel);
+        fs::create_dir_all(path.parent().unwrap()).unwrap();
+        fs::write(path, value).unwrap();
+    }
+
+    fn fixture(root: &Path) -> BuildModel {
+        write(
+            root,
+            "pom.xml",
+            r#"<project><groupId>demo</groupId><artifactId>parent</artifactId><version>1</version>
+            <packaging>pom</packaging><modules><module>lib</module><module>app</module></modules></project>"#,
+        );
+        write(
+            root,
+            "lib/pom.xml",
+            r#"<project><parent><groupId>demo</groupId><artifactId>parent</artifactId><version>1</version></parent>
+            <artifactId>lib</artifactId><build><sourceDirectory>code</sourceDirectory><resources><resource><directory>conf</directory></resource></resources></build></project>"#,
+        );
+        write(
+            root,
+            "app/pom.xml",
+            r#"<project><parent><groupId>demo</groupId><artifactId>parent</artifactId><version>1</version></parent>
+            <artifactId>app</artifactId><dependencies><dependency><groupId>demo</groupId><artifactId>lib</artifactId><version>1</version></dependency></dependencies></project>"#,
+        );
+        write(root, "lib/src/main/kotlin/Channel.kt", "value");
+        write(root, "app/src/main/resources/app.properties", "key=value");
+        write(root, "lib/conf/custom.properties", "custom=value");
+        write(root, "lib/code/Custom.java", "class Custom {}");
+        BuildModel { maven: Some(maven::load(root)), ..Default::default() }
+    }
+
+    fn fingerprint(root: &Path, model: &BuildModel) -> Option<LaunchFingerprint> {
+        launch_fingerprint(root, model, &root.join("app"), false, None, &CancellationToken::new()).unwrap()
+    }
+
+    #[test]
+    fn unchanged_inputs_match_but_source_resource_pom_add_delete_and_mtime_invalidate() {
+        for rel in [
+            "lib/src/main/kotlin/Channel.kt",
+            "app/src/main/resources/app.properties",
+            "lib/conf/custom.properties",
+            "lib/code/Custom.java",
+            "app/pom.xml",
+            "lib/pom.xml",
+            "pom.xml",
+            ".mvn/maven.config",
+            "lib/src/main/groovy/New.groovy",
+            "app/src/test/scala/Test.scala",
+        ] {
+            let dir = tempfile::tempdir().unwrap();
+            let root = dir.path();
+            let model = fixture(root);
+            let before = fingerprint(root, &model);
+            assert!(before.is_some());
+            assert_eq!(before, fingerprint(root, &model), "unchanged {rel}");
+            let serialized = serde_json::to_vec(&before).unwrap();
+            assert_eq!(before, serde_json::from_slice(&serialized).unwrap());
+            let value = if rel.ends_with("pom.xml") {
+                format!("{}<!-- changed -->", fs::read_to_string(root.join(rel)).unwrap())
+            } else {
+                "changed input".to_owned()
+            };
+            write(root, rel, &value);
+            let changed = fingerprint(root, &model);
+            assert_ne!(before, changed, "changed/added {rel}");
+            let file = fs::OpenOptions::new().write(true).open(root.join(rel)).unwrap();
+            file.set_modified(SystemTime::UNIX_EPOCH + std::time::Duration::from_secs(42)).unwrap();
+            let touched = fingerprint(root, &model);
+            assert_ne!(changed, touched, "mtime-only {rel}");
+            fs::remove_file(root.join(rel)).unwrap();
+            assert_ne!(touched, fingerprint(root, &model), "deleted {rel}");
+        }
+    }
+
+    #[test]
+    fn profile_options_jdk_goal_and_wrapper_invalidate_without_using_class_outputs() {
+        let dir = tempfile::tempdir().unwrap();
+        let root = dir.path();
+        let mut model = fixture(root);
+        let before = fingerprint(root, &model);
+        write(root, "lib/target/classes/Channel.class", "JDT stub");
+        write(root, "app/target/classes/Main.class", "JDT stub");
+        assert_eq!(before, fingerprint(root, &model));
+        let mut previous = before.clone();
+        for option in ["-Pdev", "-Pprod", "-DskipTests", "-o"] {
+            model.maven.as_mut().unwrap().projects[0].options = vec![option.into()];
+            let current = fingerprint(root, &model);
+            assert_ne!(previous, current, "{option}");
+            previous = current;
+        }
+        model.maven.as_mut().unwrap().projects[0].options.clear();
+        model.maven.as_mut().unwrap().projects[0]
+            .env
+            .insert("JAVA_HOME".into(), root.join("jdk").to_string_lossy().into_owned());
+        let jdk = fingerprint(root, &model);
+        assert_ne!(before, jdk);
+        write(root, "jdk/release", "JAVA_VERSION=21");
+        assert_ne!(jdk, fingerprint(root, &model));
+        model.maven.as_mut().unwrap().projects[0].env.clear();
+        let test = launch_fingerprint(root, &model, &root.join("app"), true, None, &CancellationToken::new())
+            .unwrap()
+            .unwrap();
+        assert_ne!(before, Some(test));
+        write(root, "mvnw", "wrapper changed");
+        assert_ne!(before, fingerprint(root, &model));
+    }
+
+    #[test]
+    fn unresolved_roots_and_cancel_never_claim_up_to_date() {
+        let dir = tempfile::tempdir().unwrap();
+        let root = dir.path();
+        let model = fixture(root);
+        write(
+            root,
+            "lib/pom.xml",
+            "<project><artifactId>lib</artifactId><build><sourceDirectory>${unknown}/src</sourceDirectory></build></project>",
+        );
+        assert!(
+            launch_fingerprint(root, &model, &root.join("app"), false, None, &CancellationToken::new())
+                .unwrap()
+                .is_none()
+        );
+        let model = fixture(root);
+        let cancel = CancellationToken::new();
+        cancel.cancel();
+        assert!(launch_fingerprint(root, &model, &root.join("app"), false, None, &cancel).is_err());
+    }
+    #[test]
+    fn external_parent_and_selected_settings_files_invalidate() {
+        let dir = tempfile::tempdir().unwrap();
+        let root = dir.path().join("project");
+        let repo = dir.path().join("repository");
+        write(
+            &repo,
+            "demo/parent/1/parent-1.pom",
+            "<project><groupId>demo</groupId><artifactId>parent</artifactId><version>1</version></project>",
+        );
+        write(
+            &root,
+            "pom.xml",
+            "<project><parent><groupId>demo</groupId><artifactId>parent</artifactId><version>1</version><relativePath/></parent><artifactId>app</artifactId></project>",
+        );
+        let mut model = crate::load(&root, &root.join("cache"), Some(repo.clone()));
+        let settings = dir.path().join("custom-settings.xml");
+        fs::write(&settings, "<settings/>").unwrap();
+        model.maven.as_mut().unwrap().projects[0].options = vec!["-s".into(), settings.to_string_lossy().into_owned()];
+        let get =
+            || launch_fingerprint(&root, &model, &root, false, Some(repo.clone()), &CancellationToken::new()).unwrap();
+        let before = get();
+        assert!(before.is_some());
+        write(
+            &repo,
+            "demo/parent/1/parent-1.pom",
+            "<project><groupId>demo</groupId><artifactId>parent</artifactId><version>1</version><!-- changed --></project>",
+        );
+        let parent = get();
+        assert_ne!(before, parent);
+        fs::write(settings, "<settings><activeProfiles><activeProfile>dev</activeProfile></activeProfiles></settings>")
+            .unwrap();
+        assert_ne!(parent, get());
+    }
+}
@@ -3,8 +3,11 @@
 //! background with cancellation and parses the compiler output into messages
 //! for the Build tool window, the Problems view and the editor.

+mod fingerprint;
 mod parse;

+pub use fingerprint::{LaunchFingerprint, launch_fingerprint};
+
 use crate::process::{self, Stream};
 use crate::{BuildModel, maven};
 use ide_core::{CancellationToken, Diagnostic, IdeError, IdeResult, Pos, Range, Severity};
@@ -234,12 +237,10 @@ fn maven_steps(root: &Path, model: &BuildModel, kind: BuildKind, module: Option<
    let Some(module) = module else { return Ok(tops.iter().map(|p| step(p, &[])).collect()) };
    // The reactor root containing the module builds it with what it depends on (`-pl … -am`).
    let rel = rel_str(root, module);
-    let top = tops
-        .iter()
-        .filter(|t| t.dir.is_empty() || rel == t.dir || rel.starts_with(&format!("{}/", t.dir)))
-        .max_by_key(|t| t.dir.len())
-        .copied()
-        .unwrap_or(tops[0]);
+    if !m.projects.iter().any(|p| p.dir == rel) {
+        return Err(IdeError::not_found("no linked Maven project found for module"));
+    }
+    let top = maven_reactor(m, &rel).ok_or_else(|| IdeError::not_found("no linked Maven project found for module"))?;
    let top_dir = subdir(root, &top.dir);
    if module == top_dir {
        return Ok(vec![step(top, &[])]);
@@ -608,6 +609,90 @@ pub fn has_non_java_sources(module: &Path) -> bool {
    walk(&module.join("src"), 12)
 }

+fn reactor_projects<'a>(m: &'a maven::MavenModel, top: &'a maven::MavenProject) -> Vec<&'a maven::MavenProject> {
+    let mut projects = Vec::new();
+    let mut pending = vec![top];
+    let mut seen = HashSet::new();
+    while let Some(p) = pending.pop() {
+        if !seen.insert(&p.pom) {
+            continue;
+        }
+        projects.push(p);
+        pending.extend(m.projects.iter().filter(|child| p.modules.contains(&child.pom)));
+    }
+    projects
+}
+
+fn maven_reactor<'a>(m: &'a maven::MavenModel, module: &str) -> Option<&'a maven::MavenProject> {
+    m.projects.iter().filter(|p| !p.aggregated).find(|top| reactor_projects(m, top).iter().any(|p| p.dir == module))
+}
+
+/// Launch module first, followed by its upstream modules in the same Maven reactor.
+/// External artifacts and unrelated linked reactors are never rebuilt for this launch.
+fn maven_launch_projects<'a>(
+    root: &Path,
+    m: &'a maven::MavenModel,
+    module: &Path,
+    test: bool,
+) -> Vec<&'a maven::MavenProject> {
+    let rel = rel_str(root, module);
+    let Some(top) = maven_reactor(m, &rel) else { return Vec::new() };
+    let reactor = reactor_projects(m, top);
+    let Some(start) = reactor.iter().find(|p| p.dir == rel) else { return Vec::new() };
+    let mut pending = vec![*start];
+    let mut seen = HashSet::new();
+    let mut projects = Vec::new();
+    while let Some(p) = pending.pop() {
+        if !seen.insert(&p.pom) {
+            continue;
+        }
+        projects.push(p);
+        for dep in &p.dependencies {
+            if !dep.resolved() || (dep.scope == "test" && (!test || p.pom != start.pom)) {
+                continue;
+            }
+            if let Some(upstream) = reactor.iter().find(|u| {
+                u.group_id == dep.group_id
+                    && u.artifact_id == dep.artifact_id
+                    && dep.version.as_ref().is_none_or(|v| *v == u.version)
+            }) {
+                pending.push(*upstream);
+            }
+        }
+    }
+    projects
+}
+
+/// Whether a launch requires the external JVM compiler. Maven includes upstream
+/// reactor dependencies; adapter selection remains a separate, module-local decision.
+pub fn launch_has_non_java_sources(root: &Path, model: &BuildModel, module: &Path, test: bool) -> bool {
+    if let Some(m) = &model.maven {
+        let projects = maven_launch_projects(root, m, module, test);
+        if !projects.is_empty() {
+            return projects.iter().any(|p| has_non_java_sources(&subdir(root, &p.dir)));
+        }
+    }
+    has_non_java_sources(module)
+}
+
+fn launch_plan(root: &Path, model: &BuildModel, module: &Path, test: bool) -> IdeResult<BuildPlan> {
+    let kind = if model.maven.as_ref().is_some_and(|m| m.projects.iter().any(|p| subdir(root, &p.dir) == module)) {
+        // JDT may have left newer error stubs in Maven's output directories.
+        BuildKind::Rebuild
+    } else {
+        BuildKind::Build
+    };
+    let mut plan = plan(root, model, kind, Some(module))?;
+    if plan.system == BuildSystem::Maven && !test {
+        for step in &mut plan.steps {
+            if let Some(goal) = step.args.last_mut() {
+                *goal = "compile".into();
+            }
+        }
+    }
+    Ok(plan)
+}
+
 /// Compiles the module at `module` with its build system before a JVM launch and
 /// returns the class directories it wrote, to put ahead of the jdtls classpath.
 pub fn build_for_launch(
@@ -617,7 +702,7 @@ pub fn build_for_launch(
    test: bool,
    cancel: &CancellationToken,
 ) -> IdeResult<Vec<PathBuf>> {
-    let plan = plan(root, model, BuildKind::Build, Some(module))?;
+    let plan = launch_plan(root, model, module, test)?;
    let result = run(root, &plan, cancel, &|_| {})?;
    if !result.success {
        let errors: Vec<String> = result
@@ -632,6 +717,14 @@ pub fn build_for_launch(
            .collect();
        return Err(IdeError::internal(format!("Build failed:\n{}", errors.join("\n"))));
    }
+    if plan.system == BuildSystem::Maven
+        && let Some(m) = &model.maven
+    {
+        return Ok(maven_launch_projects(root, m, module, test)
+            .iter()
+            .flat_map(|p| launch_class_dirs(plan.system, &subdir(root, &p.dir), test && subdir(root, &p.dir) == module))
+            .collect());
+    }
    Ok(launch_class_dirs(plan.system, module, test))
 }

@@ -818,6 +911,142 @@ mod tests {
        }
    }

+    fn reactor_model() -> BuildModel {
+        let project = |dir: &str, deps: &[&str]| maven::MavenProject {
+            pom: format!("{dir}/pom.xml"),
+            dir: dir.into(),
+            group_id: "probe".into(),
+            artifact_id: dir.into(),
+            version: "1".into(),
+            aggregated: true,
+            dependencies: deps
+                .iter()
+                .map(|d| maven::MavenDependency {
+                    group_id: "probe".into(),
+                    artifact_id: (*d).into(),
+                    version: Some("1".into()),
+                    scope: "compile".into(),
+                    ..Default::default()
+                })
+                .collect(),
+            ..Default::default()
+        };
+        let mut projects = vec![
+            project("app", &["middle"]),
+            project("middle", &["lib"]),
+            project("lib", &["app"]),
+            project("unrelated", &[]),
+        ];
+        projects.insert(
+            0,
+            maven::MavenProject {
+                pom: "pom.xml".into(),
+                artifact_id: "reactor".into(),
+                command: "mvnw".into(),
+                modules: projects.iter().map(|p| p.pom.clone()).collect(),
+                options: vec!["-s".into(), "settings.xml".into()],
+                env: BTreeMap::from([("JAVA_HOME".into(), "/jdk".into())]),
+                ..Default::default()
+            },
+        );
+        BuildModel { maven: Some(maven::MavenModel { projects, ..Default::default() }), ..Default::default() }
+    }
+
+    #[test]
+    fn mixed_launch_detection_follows_only_reactor_dependencies() {
+        for extension in ["kt", "groovy", "scala"] {
+            let tmp = tempfile::tempdir().unwrap();
+            let root = tmp.path();
+            let mut model = reactor_model();
+            write(root, "app/src/main/java/Application.java", "class Application {}");
+            write(root, &format!("unrelated/src/main/java/Other.{extension}"), "");
+            assert!(!launch_has_non_java_sources(root, &model, &root.join("app"), false));
+            write(root, &format!("lib/src/main/java/Channel.{extension}"), "");
+            assert!(launch_has_non_java_sources(root, &model, &root.join("app"), false));
+            assert_eq!(
+                maven_launch_projects(root, model.maven.as_ref().unwrap(), &root.join("app"), false).len(),
+                3,
+                "cycles terminate"
+            );
+            let m = model.maven.as_mut().unwrap();
+            m.projects[2].dependencies[0].scope = "test".into();
+            assert!(
+                !launch_has_non_java_sources(root, &model, &root.join("app"), true),
+                "upstream test dependencies are not transitive"
+            );
+            let m = model.maven.as_mut().unwrap();
+            m.projects[1].dependencies[0].scope = "test".into();
+            m.projects[2].dependencies[0].scope = "compile".into();
+            assert!(!launch_has_non_java_sources(root, &model, &root.join("app"), false));
+            assert!(launch_has_non_java_sources(root, &model, &root.join("app"), true));
+            model.maven.as_mut().unwrap().projects[2].dependencies[0].version = Some("external".into());
+            assert!(!launch_has_non_java_sources(root, &model, &root.join("app"), true));
+            model.maven.as_mut().unwrap().projects[2].dependencies[0].version = Some("1".into());
+            model.maven.as_mut().unwrap().projects[3].aggregated = false;
+            model.maven.as_mut().unwrap().projects[0].modules.retain(|p| p != "lib/pom.xml");
+            assert!(
+                !launch_has_non_java_sources(root, &model, &root.join("app"), true),
+                "another linked reactor is external"
+            );
+        }
+    }
+
+    #[test]
+    fn maven_launch_steps_use_reactor_settings_and_launch_scope() {
+        let tmp = tempfile::tempdir().unwrap();
+        let root = tmp.path();
+        write(root, "app/pom.xml", "<project/>");
+        let model = reactor_model();
+        for (test, goal) in [(false, "compile"), (true, "test-compile")] {
+            let plan = launch_plan(root, &model, &root.join("app"), test).unwrap();
+            let step = &plan.steps[0];
+            assert_eq!(step.cwd, root);
+            assert_eq!(step.program, "mvnw");
+            assert_eq!(step.env["JAVA_HOME"], "/jdk");
+            assert_eq!(
+                step.args,
+                ["-B", "-Dstyle.color=never", "-s", "settings.xml", "-pl", "app", "-am", "clean", goal]
+            );
+        }
+    }
+
+    #[cfg(unix)]
+    #[test]
+    fn external_launch_returns_upstream_outputs_and_blocks_failure_or_cancellation() {
+        use std::os::unix::fs::PermissionsExt;
+        let tmp = tempfile::tempdir().unwrap();
+        let root = tmp.path();
+        write(root, "app/pom.xml", "<project/>");
+        write(
+            root,
+            "mvnw",
+            "#!/bin/sh\nmkdir -p app/target/classes middle/target/classes lib/target/classes app/target/test-classes\n",
+        );
+        let wrapper = root.join("mvnw");
+        std::fs::set_permissions(&wrapper, std::fs::Permissions::from_mode(0o755)).unwrap();
+        let mut model = reactor_model();
+        model.maven.as_mut().unwrap().projects[0].command = wrapper.to_string_lossy().into_owned();
+        let dirs = build_for_launch(root, &model, &root.join("app"), true, &CancellationToken::new()).unwrap();
+        assert_eq!(
+            dirs,
+            ["app/target/test-classes", "app/target/classes", "middle/target/classes", "lib/target/classes"]
+                .map(|p| root.join(p))
+        );
+        write(
+            root,
+            "mvnw",
+            "#!/bin/sh\necho '[ERROR] Kotlin compilation failed: unresolved reference broken' >&2\nexit 1\n",
+        );
+        let error = build_for_launch(root, &model, &root.join("app"), false, &CancellationToken::new()).unwrap_err();
+        assert!(error.message.contains("Kotlin compilation failed"), "{}", error.message);
+        let cancel = CancellationToken::new();
+        cancel.cancel();
+        assert_eq!(
+            build_for_launch(root, &model, &root.join("app"), false, &cancel).unwrap_err().kind,
+            ide_core::error::ErrorKind::Cancelled
+        );
+    }
+
    #[test]
    fn non_java_launch_class_dirs() {
        let tmp = tempfile::tempdir().unwrap();
@@ -399,6 +399,12 @@ pub fn parse_tasks(output: &str) -> Vec<(String, GradleTask)> {
    out
 }

+/// Static fallback until Gradle has reported its tasks.
+pub(crate) fn has_war_plugin(script: &str) -> bool {
+    let script = strip_comments(script);
+    script.split(|c: char| !c.is_alphanumeric() && c != '_').any(|word| word == "war")
+}
+
 #[cfg(test)]
 mod tests {
    #[test]
@@ -0,0 +1,475 @@
+//! Private Maven builds for JDT's Kotlin binary libraries. Never use launch outputs.
+
+use crate::BuildModel;
+use crate::compile::{self, BuildEvent, BuildKind, BuildMessage};
+use ide_core::{CancellationToken, IdeError, IdeResult};
+use serde::{Deserialize, Serialize};
+use std::collections::BTreeMap;
+use std::path::{Path, PathBuf};
+
+#[derive(Clone, Debug, Deserialize)]
+#[serde(rename_all = "camelCase")]
+struct Module {
+    key: String,
+    project_uri: String,
+    output: PathBuf,
+    test_output: Option<PathBuf>,
+    dependencies: Vec<Dependency>,
+    has_kotlin: bool,
+    kotlin_goals: Vec<KotlinGoal>,
+}
+
+#[derive(Clone, Debug, Deserialize)]
+struct KotlinGoal {
+    execution: String,
+    status: String,
+}
+
+#[derive(Clone, Debug, Deserialize)]
+struct Dependency {
+    key: String,
+    scope: String,
+    #[serde(rename = "type")]
+    kind: Option<String>,
+    classifier: Option<String>,
+}
+
+#[derive(Clone, Debug, Serialize, PartialEq, Eq)]
+pub struct Library {
+    pub path: PathBuf,
+    pub test: bool,
+}
+
+#[derive(Clone, Debug, Serialize, PartialEq, Eq)]
+#[serde(rename_all = "camelCase")]
+pub struct ProjectLibraries {
+    pub project_uri: String,
+    pub libraries: Vec<Library>,
+}
+
+pub struct Outcome {
+    pub projects: Vec<ProjectLibraries>,
+    pub messages: Vec<BuildMessage>,
+    pub success: bool,
+}
+
+/// Inspect sources, excluding generated/build/VCS trees and never following symlinks.
+pub fn has_kotlin(root: &Path) -> bool {
+    let Ok(entries) = std::fs::read_dir(root) else { return false };
+    entries.flatten().any(|entry| {
+        let Ok(kind) = entry.file_type() else { return false };
+        if kind.is_file() {
+            entry.path().extension().is_some_and(|e| e == "kt")
+        } else {
+            kind.is_dir()
+                && !matches!(
+                    entry.file_name().to_str(),
+                    Some("target" | "build" | "out" | "bin" | "node_modules" | ".git" | ".openidea")
+                )
+                && has_kotlin(&entry.path())
+        }
+    })
+}
+
+/// Run the project's configured wrapper/settings/JDK and lifecycle, with an output
+/// redirector loaded before Maven calculates its lifecycle execution plans.
+pub fn build(
+    root: &Path,
+    model: &BuildModel,
+    bundle: &Path,
+    generation: &Path,
+    cancel: &CancellationToken,
+) -> IdeResult<Outcome> {
+    std::fs::create_dir_all(generation)?;
+    let mut plan = compile::plan(root, model, BuildKind::Build, None)?;
+    if plan.system != compile::BuildSystem::Maven {
+        return Err(IdeError::invalid("Kotlin bridge requires a Maven build root"));
+    }
+    let mut manifests = Vec::new();
+    for (index, step) in plan.steps.iter_mut().enumerate() {
+        step.args.push("--fail-at-end".into());
+        let directory = generation.join(format!("reactor-{index}"));
+        std::fs::create_dir_all(&directory)?;
+        manifests.push(directory.join("modules.json"));
+        let mut extensions = vec![bundle.to_path_buf()];
+        step.args.retain(|arg| {
+            if let Some(value) = arg.strip_prefix("-Dmaven.ext.class.path=") {
+                extensions.extend(std::env::split_paths(value));
+                false
+            } else {
+                true
+            }
+        });
+        let extension_path = std::env::join_paths(extensions).map_err(|e| IdeError::invalid(e.to_string()))?;
+        step.args.push(format!("-Dmaven.ext.class.path={}", extension_path.to_string_lossy()));
+        step.args.push(format!("-Dopenidea.kotlin.staging={}", directory.join("staging").display()));
+    }
+    let mut messages = Vec::new();
+    // Independent linked reactors must still run after another reactor's javac fails.
+    for step in &plan.steps {
+        let mut reactor = plan.clone();
+        reactor.steps = vec![step.clone()];
+        let result = compile::run(root, &reactor, cancel, &|event| {
+            if let BuildEvent::Output { text, .. } = event {
+                tracing::debug!("kotlin bridge: {}", text.trim_end());
+            }
+        })?;
+        messages.extend(result.messages);
+    }
+    // javac diagnostics belong to JDT, including when a Kotlin target was skipped.
+    messages.retain(|message| {
+        message.path.as_ref().is_some_and(|path| PathBuf::from(path.clone()).extension().is_some_and(|e| e == "kt"))
+    });
+    let mut modules = Vec::new();
+    for manifest in manifests {
+        let parsed: Vec<Module> = serde_json::from_slice(&std::fs::read(manifest)?)
+            .map_err(|e| IdeError::internal(format!("Kotlin module manifest: {e}")))?;
+        modules.extend(parsed);
+    }
+    messages.extend(kotlin_failures(&modules));
+    if messages.iter().any(|message| message.severity == ide_core::Severity::Error) {
+        return Ok(Outcome { projects: Vec::new(), messages, success: false });
+    }
+    let pending = generation.join("libraries.pending");
+    let published = generation.join("libraries");
+    std::fs::create_dir_all(&pending)?;
+    let mut libraries = BTreeMap::new();
+    for (index, module) in modules.iter().enumerate() {
+        let mut outputs = ModuleLibraries::default();
+        for (source, target, name) in [
+            (Some(&module.output), &mut outputs.main, format!("main-{index}")),
+            (module.test_output.as_ref(), &mut outputs.test, format!("test-{index}")),
+        ] {
+            let Some(source) = source else { continue };
+            if !source.starts_with(generation) {
+                return Err(IdeError::internal("Kotlin build output escaped staging"));
+            }
+            if copy_kotlin(source, &pending.join(&name), cancel)? {
+                *target = Some(published.join(name));
+            }
+        }
+        libraries.insert(module.key.clone(), outputs);
+    }
+    publish(&pending, &published, cancel)?;
+    Ok(Outcome { projects: consumers(&modules, &libraries), messages, success: true })
+}
+
+fn kotlin_failures(modules: &[Module]) -> Vec<BuildMessage> {
+    let mut messages = Vec::new();
+    for module in modules {
+        if !module.has_kotlin {
+            continue;
+        }
+        if module.kotlin_goals.is_empty() {
+            messages.push(kotlin_failure(module, "compile target was not executed"));
+        }
+        for goal in &module.kotlin_goals {
+            if goal.status != "success" {
+                messages.push(kotlin_failure(module, &format!("{} {}", goal.execution, goal.status)));
+            }
+        }
+    }
+    messages
+}
+
+fn kotlin_failure(module: &Module, reason: &str) -> BuildMessage {
+    BuildMessage {
+        severity: ide_core::Severity::Error,
+        text: format!("Kotlin compilation for {}: {reason}", module.key),
+        path: None,
+        range: None,
+        code: None,
+    }
+}
+
+fn publish(pending: &Path, published: &Path, cancel: &CancellationToken) -> IdeResult<()> {
+    if cancel.is_cancelled() {
+        return Err(IdeError::cancelled());
+    }
+    std::fs::rename(pending, published)?;
+    Ok(())
+}
+
+#[derive(Default)]
+struct ModuleLibraries {
+    main: Option<PathBuf>,
+    test: Option<PathBuf>,
+}
+
+fn consumers(modules: &[Module], libraries: &BTreeMap<String, ModuleLibraries>) -> Vec<ProjectLibraries> {
+    modules
+        .iter()
+        .map(|consumer| {
+            let mut visible = Vec::<Library>::new();
+            let mut add = |path: &Option<PathBuf>, test: bool| {
+                if let Some(path) = path {
+                    if let Some(previous) = visible.iter_mut().find(|entry| &entry.path == path) {
+                        previous.test &= test;
+                    } else {
+                        visible.push(Library { path: path.clone(), test });
+                    }
+                }
+            };
+            if let Some(own) = libraries.get(&consumer.key) {
+                add(&own.test, true);
+                add(&own.main, false);
+            }
+            // Maven's resolved artifacts already apply exclusions, mediation and optional
+            // propagation. Preserve their classpath order, after the module's own output.
+            for dependency in &consumer.dependencies {
+                let Some(output) = libraries.get(&dependency.key) else { continue };
+                let test = match dependency.scope.as_str() {
+                    "compile" | "provided" | "system" | "" => false,
+                    "test" | "runtime" => true,
+                    _ => continue,
+                };
+                match (dependency.kind.as_deref(), dependency.classifier.as_deref()) {
+                    (Some("test-jar"), None | Some("tests")) | (Some("jar"), Some("tests")) => add(&output.test, test),
+                    (None | Some("jar"), None | Some("")) => add(&output.main, test),
+                    _ => {}
+                }
+            }
+            ProjectLibraries { project_uri: consumer.project_uri.clone(), libraries: visible }
+        })
+        .collect()
+}
+
+fn copy_kotlin(source: &Path, destination: &Path, cancel: &CancellationToken) -> IdeResult<bool> {
+    let Ok(entries) = std::fs::read_dir(source) else { return Ok(false) };
+    let mut found = false;
+    for entry in entries {
+        if cancel.is_cancelled() {
+            return Err(IdeError::cancelled());
+        }
+        let entry = entry?;
+        let kind = entry.file_type()?;
+        let path = entry.path();
+        let output = destination.join(entry.file_name());
+        if kind.is_dir() {
+            found |= copy_kotlin(&path, &output, cancel)?;
+        } else if kind.is_file() {
+            let bytes = std::fs::read(&path)?;
+            let class = path.extension().is_some_and(|e| e == "class");
+            let metadata = path.extension().is_some_and(|e| e == "kotlin_module");
+            if metadata || (class && kotlin_class(&bytes).unwrap_or(false)) {
+                std::fs::create_dir_all(destination)?;
+                std::fs::write(output, bytes)?;
+                found |= class;
+            }
+        }
+    }
+    Ok(found)
+}
+
+/// Read the actual class-level SourceFile attribute, rather than searching strings
+/// (a Java constant containing "Something.kt" must never become a Kotlin library).
+fn kotlin_class(bytes: &[u8]) -> Option<bool> {
+    struct Reader<'a> {
+        bytes: &'a [u8],
+        pos: usize,
+    }
+    impl<'a> Reader<'a> {
+        fn take(&mut self, count: usize) -> Option<&'a [u8]> {
+            let value = self.bytes.get(self.pos..self.pos.checked_add(count)?)?;
+            self.pos += count;
+            Some(value)
+        }
+        fn u2(&mut self) -> Option<usize> {
+            Some(u16::from_be_bytes(self.take(2)?.try_into().ok()?) as usize)
+        }
+        fn u4(&mut self) -> Option<usize> {
+            Some(u32::from_be_bytes(self.take(4)?.try_into().ok()?) as usize)
+        }
+        fn attributes(&mut self) -> Option<()> {
+            for _ in 0..self.u2()? {
+                self.u2()?;
+                let n = self.u4()?;
+                self.take(n)?;
+            }
+            Some(())
+        }
+    }
+    let mut reader = Reader { bytes, pos: 0 };
+    if reader.take(4)? != [0xca, 0xfe, 0xba, 0xbe] {
+        return None;
+    }
+    reader.take(4)?;
+    let count = reader.u2()?;
+    let mut utf8 = BTreeMap::new();
+    let mut index = 1;
+    while index < count {
+        match reader.take(1)?[0] {
+            1 => {
+                let n = reader.u2()?;
+                utf8.insert(index, reader.take(n)?);
+            }
+            3 | 4 | 9..=12 | 17 | 18 => {
+                reader.take(4)?;
+            }
+            5 | 6 => {
+                reader.take(8)?;
+                index += 1;
+            }
+            7 | 8 | 16 | 19 | 20 => {
+                reader.take(2)?;
+            }
+            15 => {
+                reader.take(3)?;
+            }
+            _ => return None,
+        }
+        index += 1;
+    }
+    reader.take(6)?;
+    let interfaces = reader.u2()?;
+    reader.take(interfaces.checked_mul(2)?)?;
+    for _ in 0..2 {
+        for _ in 0..reader.u2()? {
+            reader.take(6)?;
+            reader.attributes()?;
+        }
+    }
+    for _ in 0..reader.u2()? {
+        let name = reader.u2()?;
+        let length = reader.u4()?;
+        if utf8.get(&name).copied() == Some(b"SourceFile".as_slice()) && length == 2 {
+            let source = reader.u2()?;
+            return Some(utf8.get(&source)?.ends_with(b".kt"));
+        }
+        reader.take(length)?;
+    }
+    Some(false)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn every_kotlin_target_must_succeed_even_when_maven_fails_elsewhere() {
+        let mut modules: Vec<Module> = serde_json::from_str(r#"[
+            {"key":"lib","projectUri":"lib","output":"lib","dependencies":[],"hasKotlin":true,
+             "kotlinGoals":[{"execution":"main:compile","status":"success"},{"execution":"test:test-compile","status":"success"}]},
+            {"key":"java","projectUri":"java","output":"java","dependencies":[],"hasKotlin":false,"kotlinGoals":[]}
+        ]"#).unwrap();
+        assert!(kotlin_failures(&modules).is_empty());
+        for status in ["failed", "skipped"] {
+            modules[0].kotlin_goals[1].status = status.into();
+            let failures = kotlin_failures(&modules);
+            assert_eq!(failures.len(), 1);
+            assert!(failures[0].text.contains(&format!("test:test-compile {status}")));
+        }
+        modules[0].kotlin_goals.clear();
+        assert_eq!(kotlin_failures(&modules).len(), 1);
+        modules[0].has_kotlin = false;
+        assert!(kotlin_failures(&modules).is_empty());
+        assert!(
+            serde_json::from_str::<Vec<Module>>(
+                r#"[{"key":"old","projectUri":"old","output":"old","dependencies":[]}]"#
+            )
+            .is_err()
+        );
+    }
+
+    #[test]
+    fn respects_mavens_resolved_closure_and_scopes() {
+        let json = r#"[
+          {"key":"zapp","projectUri":"app","output":"app", "hasKotlin":false,"kotlinGoals":[],"dependencies":[{"key":"mid","scope":"compile","optional":false},{"key":"lib","scope":"compile","optional":false}]},
+          {"key":"mid","projectUri":"mid","output":"mid", "hasKotlin":false,"kotlinGoals":[],"dependencies":[
+            {"key":"lib","scope":"compile","optional":false},
+            {"key":"optional","scope":"compile","optional":true},
+            {"key":"test","scope":"test","optional":false},
+            {"key":"provided","scope":"provided","optional":false}]},
+          {"key":"lib","projectUri":"lib","output":"lib","hasKotlin":false,"kotlinGoals":[],"dependencies":[]}
+        ]"#;
+        let modules: Vec<Module> = serde_json::from_str(json).unwrap();
+        let libraries = ["zapp", "lib", "optional", "test", "provided"]
+            .into_iter()
+            .map(|key| (key.to_owned(), ModuleLibraries { main: Some(PathBuf::from(key)), test: None }))
+            .collect();
+        let result = consumers(&modules, &libraries);
+        assert_eq!(
+            result[0].libraries,
+            vec![Library { path: "zapp".into(), test: false }, Library { path: "lib".into(), test: false },]
+        );
+        assert_eq!(result[1].libraries.len(), 4);
+        assert!(result[1].libraries.iter().find(|l| l.path == Path::new("test")).unwrap().test);
+    }
+
+    #[test]
+    fn test_outputs_are_private_unless_maven_resolves_a_test_jar() {
+        let modules: Vec<Module> = serde_json::from_str(r#"[
+          {"key":"lib","projectUri":"lib","output":"lib","hasKotlin":false,"kotlinGoals":[],"dependencies":[]},
+          {"key":"app","projectUri":"app","output":"app","hasKotlin":false,"kotlinGoals":[],"dependencies":[{"key":"lib","scope":"compile","type":"jar","classifier":null}]},
+          {"key":"test-app","projectUri":"test-app","output":"app","hasKotlin":false,"kotlinGoals":[],"dependencies":[{"key":"lib","scope":"test","type":"test-jar","classifier":"tests"}]}
+        ]"#).unwrap();
+        let libraries =
+            BTreeMap::from([("lib".into(), ModuleLibraries { main: Some("main".into()), test: Some("test".into()) })]);
+        let result = consumers(&modules, &libraries);
+        assert_eq!(
+            result[0].libraries,
+            vec![Library { path: "test".into(), test: true }, Library { path: "main".into(), test: false }]
+        );
+        assert_eq!(result[1].libraries, vec![Library { path: "main".into(), test: false }]);
+        assert_eq!(result[2].libraries, vec![Library { path: "test".into(), test: true }]);
+    }
+
+    #[test]
+    fn publishes_complete_directories_and_cancellation_keeps_them_private() {
+        let directory = tempfile::tempdir().unwrap();
+        let pending = directory.path().join("pending");
+        let final_path = directory.path().join("published");
+        std::fs::create_dir(&pending).unwrap();
+        std::fs::write(pending.join("Channel.class"), "complete").unwrap();
+        let cancelled = CancellationToken::new();
+        cancelled.cancel();
+        assert!(publish(&pending, &final_path, &cancelled).is_err());
+        assert!(!final_path.exists());
+        assert!(pending.exists());
+        publish(&pending, &final_path, &CancellationToken::new()).unwrap();
+        assert!(!pending.exists());
+        assert_eq!(std::fs::read(final_path.join("Channel.class")).unwrap(), b"complete");
+    }
+
+    #[test]
+    fn never_runs_another_build_system_with_maven_output_properties() {
+        let directory = tempfile::tempdir().unwrap();
+        std::fs::write(directory.path().join("Cargo.toml"), "").unwrap();
+        let error = build(
+            directory.path(),
+            &BuildModel::default(),
+            Path::new("unused.jar"),
+            &directory.path().join("private"),
+            &CancellationToken::new(),
+        )
+        .err()
+        .unwrap();
+        assert_eq!(error.message, "Kotlin bridge requires a Maven build root");
+    }
+
+    #[test]
+    fn does_not_find_deleted_sources_in_build_outputs() {
+        let dir = tempfile::tempdir().unwrap();
+        std::fs::create_dir_all(dir.path().join("target/generated")).unwrap();
+        std::fs::write(dir.path().join("target/generated/Old.kt"), "").unwrap();
+        assert!(!has_kotlin(dir.path()));
+        std::fs::write(dir.path().join("New.kt"), "").unwrap();
+        assert!(has_kotlin(dir.path()));
+    }
+
+    #[test]
+    fn parses_sourcefile_and_rejects_truncated_classes() {
+        let mut class = vec![0xca, 0xfe, 0xba, 0xbe, 0, 0, 0, 52, 0, 3, 1, 0, 10];
+        class.extend_from_slice(b"SourceFile");
+        class.extend_from_slice(&[1, 0, 10]);
+        class.extend_from_slice(b"Channel.kt");
+        class.extend_from_slice(&[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 2, 0, 2]);
+        assert_eq!(kotlin_class(&class), Some(true));
+        for end in 0..class.len() {
+            assert!(kotlin_class(&class[..end]).is_none());
+        }
+        let offset = 26;
+        class[offset..offset + 10].copy_from_slice(b"Other.java");
+        assert_eq!(kotlin_class(&class), Some(false));
+    }
+}
@@ -5,12 +5,15 @@
 //! and merges what the last sync ([`sync_maven`] / [`sync_gradle`], which run
 //! Maven / Gradle in the background) cached for the project.

+pub mod application_update;
 pub mod compile;
 pub mod gradle;
+pub mod kotlin_bridge;
 pub mod maven;
 pub mod pom_edit;
 mod process;
 mod sync;
+pub mod web;
 mod xml;

 pub use gradle::{GradleModel, GradleProject, GradleTask};
@@ -39,8 +42,19 @@ pub struct BuildModel {
 /// Static model of the builds under `root`, merged with the sync results cached in `cache_dir`.
 /// Parent POMs are looked up in `maven_repo` (the configured local repository), else the default one.
 pub fn load(root: &Path, cache_dir: &Path, maven_repo: Option<PathBuf>) -> BuildModel {
+    load_linked(root, cache_dir, maven_repo, &ide_core::settings::MavenSettings::default())
+}
+
+/// Loads only linked Maven reactors, retaining an empty model so projects can be re-added.
+pub fn load_linked(
+    root: &Path,
+    cache_dir: &Path,
+    maven_repo: Option<PathBuf>,
+    settings: &ide_core::settings::MavenSettings,
+) -> BuildModel {
    let maven = maven::is_maven_project(root).then(|| {
        let mut m = maven::load_with_repo(root, maven_repo.or_else(maven::default_local_repo));
+        maven::UnlinkedProjects::from_model(&m, settings).filter(&mut m);
        sync::apply_maven_cache(root, cache_dir, &mut m);
        m
    });
@@ -401,6 +401,9 @@ struct Inherited {
    managed: Vec<RawDep>,
    plugins: Vec<RawPlugin>,
    managed_plugins: Vec<RawPlugin>,
+    /// `<id>`, `activeByDefault`: profiles of the POM and its ancestors —
+    /// Maven lets a child enable a parent's profiles with `-P`.
+    profiles: Vec<(String, bool)>,
 }

 fn merge_by<T: Clone>(base: &mut Vec<T>, own: &[T], key: impl Fn(&T) -> String) {
@@ -523,6 +526,11 @@ impl Resolver {
            merge_by(&mut ctx.deps, &p.deps, RawDep::key);
            merge_plugins(&mut ctx.plugins, &p.plugins);
        }
+        merge_by(
+            &mut ctx.profiles,
+            &pom.profiles.iter().map(|p| (p.id.clone(), p.active_by_default)).collect::<Vec<_>>(),
+            |(id, _)| id.clone(),
+        );
        // Managed dependencies: own entries win; imported BOMs fill the gaps.
        let props = self.properties_for(&pom, &ctx, &dir);
        let mut imported: Vec<RawDep> = Vec::new();
@@ -593,6 +601,72 @@ impl Resolver {
    }
 }

+/// Files and source/resource trees consumed by a launch build. Unresolved custom
+/// roots disable reuse rather than silently omitting an input.
+pub(crate) fn launch_inputs(
+    root: &Path,
+    projects: &[&MavenProject],
+    local_repo: Option<PathBuf>,
+) -> Option<Vec<PathBuf>> {
+    fn roots(el: &Element, parent: &str, dir: &Path, out: &mut Vec<PathBuf>) -> Option<()> {
+        let input =
+            matches!(el.name.as_str(), "sourceDirectory" | "testSourceDirectory" | "sourceDir" | "testSourceDir")
+                || (matches!(parent, "sources" | "sourceDirs" | "testSources" | "testSourceDirs")
+                    && matches!(el.name.as_str(), "source" | "sourceDir" | "testSourceDir"))
+                || (matches!(parent, "resource" | "testResource" | "source" | "testSource") && el.name == "directory")
+                || (parent == "filters" && el.name == "filter");
+        // Profile activation may depend on the presence of an otherwise unrelated file.
+        let activation = parent == "file" && matches!(el.name.as_str(), "exists" | "missing");
+        if input || activation {
+            // Other properties can be overridden by -D, profiles or settings.
+            // Without Maven's effective roots, conservatively disable reuse for them.
+            let value = el
+                .text
+                .trim()
+                .replace("${project.basedir}", &dir.to_string_lossy())
+                .replace("${basedir}", &dir.to_string_lossy());
+            if value.contains("${") {
+                return None;
+            }
+            if !value.is_empty() {
+                out.push(dir.join(value));
+            }
+        }
+        for child in &el.children {
+            roots(child, &el.name, dir, out)?;
+        }
+        Some(())
+    }
+    let mut resolver = Resolver::new(local_repo.or_else(default_local_repo));
+    let mut out = Vec::new();
+    for project in projects {
+        let dir = root.join(&project.dir);
+        // Include all conventional language/resource roots, including nonstandard files under src.
+        out.push(dir.join("src"));
+        let pom = root.join(&project.pom);
+        resolver.context(&pom, 0);
+        let mut path = pom;
+        let mut seen = HashSet::new();
+        loop {
+            let canonical = dunce::canonicalize(&path).ok()?;
+            if !seen.insert(canonical) || seen.len() > MAX_PARENT_DEPTH {
+                return None;
+            }
+            out.push(path.clone());
+            let text = std::fs::read_to_string(&path).ok()?;
+            roots(&xml::parse(&text)?, "", &dir, &mut out)?;
+            let raw = resolver.pom(&path)?;
+            let Some(parent) = raw.parent else { break };
+            path = resolver.parent_path(path.parent()?, &parent)?;
+        }
+    }
+    // Also track imported BOMs read while resolving inheritance.
+    out.extend(resolver.poms.into_keys());
+    out.sort();
+    out.dedup();
+    Some(out)
+}
+
 // ---------------------------------------------------------------- plugins

 /// `maven-clean-plugin` → `clean`, `spring-boot-maven-plugin` → `spring-boot`.
@@ -935,9 +1009,10 @@ pub(crate) fn load_with_repo(root: &Path, local_repo: Option<PathBuf>) -> MavenM
            .or_else(|| pom.compiler_release.as_deref().map(i))
            .and_then(|v| java_version(&v));

-        for p in &pom.profiles {
-            if !model.profiles.iter().any(|x| x.id == p.id) {
-                model.profiles.push(MavenProfile { id: p.id.clone(), active_by_default: p.active_by_default });
+        // The project can activate the profiles of its own POM and its ancestors'.
+        for (id, active) in &ctx.profiles {
+            if !model.profiles.iter().any(|x| x.id == *id) {
+                model.profiles.push(MavenProfile { id: id.clone(), active_by_default: *active });
            }
        }
        let artifact_id = i(&pom.artifact_id);
@@ -954,7 +1029,7 @@ pub(crate) fn load_with_repo(root: &Path, local_repo: Option<PathBuf>) -> MavenM
            aggregated,
            plugins,
            dependencies,
-            profiles: pom.profiles.iter().map(|p| p.id.clone()).collect(),
+            profiles: ctx.profiles.iter().map(|(id, _)| id.clone()).collect(),
            java_version: jv,
            command: wrapper(root, &dir),
            options: Vec::new(),
@@ -967,6 +1042,67 @@ pub(crate) fn load_with_repo(root: &Path, local_repo: Option<PathBuf>) -> MavenM
    model
 }

+/// Shared linkage decision for every Maven consumer, including modules outside a reactor directory.
+#[derive(Default)]
+pub struct UnlinkedProjects {
+    poms: std::collections::BTreeSet<String>,
+}
+
+impl UnlinkedProjects {
+    pub fn load(root: &Path, settings: &ide_core::settings::MavenSettings) -> Self {
+        if settings.unlinked_projects.is_empty() {
+            return Self::default();
+        }
+        Self::from_model(&load(root), settings)
+    }
+
+    pub fn from_model(model: &MavenModel, settings: &ide_core::settings::MavenSettings) -> Self {
+        let mut result = Self::default();
+        let mut pending = settings.unlinked_projects.clone();
+        while let Some(pom) = pending.pop() {
+            let pom = normalized_pom(&pom);
+            if !result.poms.insert(pom.clone()) {
+                continue;
+            }
+            if let Some(project) = model.projects.iter().find(|p| normalized_pom(&p.pom) == pom) {
+                pending.extend(project.modules.iter().cloned());
+            }
+        }
+        result
+    }
+
+    pub fn contains(&self, pom: &str) -> bool {
+        self.poms.contains(&normalized_pom(pom))
+    }
+
+    pub fn poms(&self) -> impl Iterator<Item = &str> {
+        self.poms.iter().map(String::as_str)
+    }
+
+    pub fn filter(&self, model: &mut MavenModel) {
+        model.projects.retain(|p| !self.contains(&p.pom));
+        for project in &mut model.projects {
+            project.modules.retain(|p| !self.contains(p));
+        }
+        model.profiles.retain(|p| model.projects.iter().any(|project| project.profiles.contains(&p.id)));
+    }
+}
+
+fn normalized_pom(pom: &str) -> String {
+    let pom = pom.replace('\\', "/");
+    let mut parts = Vec::new();
+    for part in pom.split('/') {
+        match part {
+            "" | "." => {}
+            ".." if parts.last().is_some_and(|p| *p != "..") => {
+                parts.pop();
+            }
+            part => parts.push(part),
+        }
+    }
+    parts.join("/")
+}
+
 /// Every POM of the model (for change detection).
 pub fn build_files(root: &Path, model: &MavenModel) -> Vec<PathBuf> {
    model.projects.iter().map(|p| root.join(&p.pom)).collect()
@@ -1219,9 +1355,41 @@ mod tests {
        let profiles: Vec<(&str, bool)> = model.profiles.iter().map(|p| (p.id.as_str(), p.active_by_default)).collect();
        assert_eq!(profiles, [("dev", true), ("extra", false)]);
        assert_eq!(parent.profiles, ["dev", "extra"]);
+        assert_eq!(core.profiles, ["dev", "extra"], "a module inherits its parent's profiles");
        assert!(model.projects.iter().all(|p| p.command == if cfg!(windows) { "mvn.cmd" } else { "mvn" }));
    }

+    #[test]
+    fn profiles_of_a_parent_pom_are_inherited() {
+        let tmp = tempfile::tempdir().unwrap();
+        let root = tmp.path();
+        write(
+            root,
+            "pom.xml",
+            r#"<project><groupId>demo</groupId><artifactId>parent</artifactId><version>1.0</version>
+              <packaging>pom</packaging><modules><module>child</module></modules>
+              <profiles>
+                <profile><id>jdk8</id></profile>
+                <profile><id>jdk21</id><activation><activeByDefault>true</activeByDefault></activation></profile>
+              </profiles>
+            </project>"#,
+        );
+        write(
+            root,
+            "child/pom.xml",
+            r#"<project><parent><groupId>demo</groupId><artifactId>parent</artifactId><version>1.0</version></parent>
+              <artifactId>child</artifactId>
+              <profiles><profile><id>own</id></profile></profiles>
+            </project>"#,
+        );
+        let model = load_with_repo(root, None);
+        let child = &model.projects[1];
+        // `-Pjdk8` on the module activates the parent's profile, so it is listed.
+        assert_eq!(child.profiles, ["jdk8", "jdk21", "own"]);
+        let profiles: Vec<(&str, bool)> = model.profiles.iter().map(|p| (p.id.as_str(), p.active_by_default)).collect();
+        assert_eq!(profiles, [("jdk8", false), ("jdk21", true), ("own", false)]);
+    }
+
    #[test]
    fn parent_and_bom_from_the_local_repository_and_wrapper() {
        let tmp = tempfile::tempdir().unwrap();
@@ -1459,3 +1627,45 @@ mod tests {
        }
    }
 }
+
+#[cfg(test)]
+mod linkage_tests {
+    use super::*;
+    use ide_core::settings::MavenSettings;
+
+    #[test]
+    fn excludes_reactor_modules_and_profiles_but_keeps_other_roots() {
+        let tmp = tempfile::tempdir().unwrap();
+        let root = tmp.path();
+        for (name, body) in [
+            (
+                "a",
+                "<modules><module>child</module><module>../shared</module></modules><profiles><profile><id>only-a</id></profile></profiles>",
+            ),
+            ("a/child", ""),
+            ("shared", ""),
+            ("b", ""),
+        ] {
+            std::fs::create_dir_all(root.join(name)).unwrap();
+            std::fs::write(
+                root.join(name).join("pom.xml"),
+                format!("<project><artifactId>{name}</artifactId>{body}</project>"),
+            )
+            .unwrap();
+        }
+        let original = load_with_repo(root, None);
+        let settings = MavenSettings { unlinked_projects: vec!["./a/pom.xml".into()], ..Default::default() };
+        let unlinked = UnlinkedProjects::from_model(&original, &settings);
+        assert!(unlinked.contains("a/child/pom.xml"));
+        assert!(unlinked.contains("shared/pom.xml"));
+        assert!(unlinked.contains("a/../shared/pom.xml"));
+        assert!(!unlinked.contains("b/pom.xml"));
+        let mut model = original.clone();
+        unlinked.filter(&mut model);
+        assert_eq!(model.projects.iter().map(|p| p.pom.as_str()).collect::<Vec<_>>(), ["b/pom.xml"]);
+        assert!(model.profiles.is_empty());
+        let mut restored = original.clone();
+        UnlinkedProjects::from_model(&original, &MavenSettings::default()).filter(&mut restored);
+        assert_eq!(restored, original);
+    }
+}
@@ -34,6 +34,22 @@ fn kill_tree(child: &mut Child) {
    let _ = child.wait();
 }

+/// `program` as spawnable: a bare name (`mvn`, `mvn.cmd`) resolves on the IDE's
+/// search path — the login shell's `PATH` plus version-manager shims — since the
+/// app's own `PATH` can be minimal and `Command` would not see `mvn` there.
+pub(crate) fn program_path(program: &str, env: &BTreeMap<String, String>) -> std::path::PathBuf {
+    let path = std::path::Path::new(program);
+    if !path.is_relative() || path.components().count() > 1 {
+        return path.to_path_buf();
+    }
+    let search = env
+        .iter()
+        .find(|(k, _)| k.eq_ignore_ascii_case("PATH"))
+        .map(|(_, v)| std::ffi::OsString::from(v))
+        .unwrap_or_else(ide_core::tool_path::search_path);
+    ide_core::process::find_executable(program, &search).unwrap_or_else(|| path.to_path_buf())
+}
+
 /// Runs `program args` in `cwd`, feeding each output line to `on_line`; kills
 /// the process group and returns `cancelled` when `cancel` fires.
 pub(crate) fn run(
@@ -42,14 +58,27 @@ pub(crate) fn run(
    cwd: &Path,
    env: &BTreeMap<String, String>,
    cancel: &CancellationToken,
+    on_line: impl FnMut(Stream, &str),
+) -> IdeResult<Output> {
+    run_with_env(program, args, cwd, env, false, cancel, on_line)
+}
+
+pub(crate) fn run_with_env(
+    program: &str,
+    args: &[String],
+    cwd: &Path,
+    env: &BTreeMap<String, String>,
+    clear_env: bool,
+    cancel: &CancellationToken,
    mut on_line: impl FnMut(Stream, &str),
 ) -> IdeResult<Output> {
    tracing::info!("build: {program} {} (in {})", args.join(" "), cwd.display());
    // Output is read as UTF-8: JVMs on Windows are told to write it (see `ide_core::output_encoding`).
    let encoding =
        ide_core::output_encoding::fix(program, args, env, |k| std::env::var(k).ok(), "UTF-8", cfg!(windows));
-    let mut command = Command::new(program);
-    command.args(args).current_dir(cwd).envs(env).envs(encoding.env).stdin(Stdio::null());
+    let program = program_path(program, env);
+    let mut command = Command::new(&program);
+    command.args(args).current_dir(cwd).envs(env).envs(encoding.env.iter().map(|(k, v)| (k, v))).stdin(Stdio::null());
    command.stdout(Stdio::piped()).stderr(Stdio::piped());
    #[cfg(unix)]
    {
@@ -57,7 +86,11 @@ pub(crate) fn run(
        command.process_group(0);
    }
    ide_core::process::prepare(&mut command);
-    let mut child = command.spawn().map_err(|e| IdeError::unavailable(format!("cannot start {program}: {e}")))?;
+    if clear_env {
+        command.env_clear().envs(env).envs(encoding.env);
+    }
+    let mut child =
+        command.spawn().map_err(|e| IdeError::unavailable(format!("cannot start {}: {e}", program.display())))?;
    let (tx, rx) = mpsc::channel::<(Stream, String)>();
    let pump = |stream: Box<dyn Read + Send>, kind: Stream, tx: mpsc::Sender<(Stream, String)>| {
        std::thread::spawn(move || {
@@ -68,7 +101,7 @@ pub(crate) fn run(
                match reader.read_until(b'\n', &mut buf) {
                    Ok(0) | Err(_) => break,
                    Ok(_) => {
-                        let line = String::from_utf8_lossy(&buf);
+                        let line = ide_core::output_encoding::decode_tool_output(&buf);
                        let line = line.trim_end_matches(['\n', '\r']).to_owned();
                        if tx.send((kind, line)).is_err() {
                            break;
@@ -23,6 +23,7 @@ pub struct SyncProgress {

 #[derive(Clone, Debug, Default)]
 pub struct SyncOptions {
+    pub maven_settings: ide_core::settings::MavenSettings,
    /// `-o` / `--offline`.
    pub offline: bool,
    /// Maven profiles (`-P`), `!id` deactivates.
@@ -31,6 +32,8 @@ pub struct SyncOptions {
    pub env: BTreeMap<String, String>,
    /// Maven launcher replacing the project's `mvnw` / `mvn` (Settings › Maven home).
    pub maven_command: Option<String>,
+    /// Resolved Gradle launcher from Settings.
+    pub gradle_command: Option<String>,
    /// Maven options before the goals (`-s`, `-Dmaven.repo.local=`).
    pub maven_options: Vec<String>,
 }
@@ -118,6 +121,16 @@ fn now_ms() -> f64 {
 /// Merges the cached effective build into `model`.
 pub fn apply_maven_cache(root: &Path, cache_dir: &Path, model: &mut MavenModel) {
    let Some(cache) = read_cache::<MavenCache>(cache_dir, MAVEN_CACHE) else { return };
+    model.synced_at = Some(cache.at_ms);
+    model.sync_error = cache.error;
+    let changed = cache.hash != hash_files(&maven::build_files(root, model));
+    model.stale = !cache.verbose || changed;
+    // A cache older than the current build files: its effective-POM plugins and
+    // resolved dependencies would hide what the POMs declare now (a just added
+    // dependency never appears). The static parse stays until Reload.
+    if changed {
+        return;
+    }
    for p in &mut model.projects {
        if let Some(c) = cache.projects.iter().find(|c| c.key == p.key()) {
            if !c.plugins.is_empty() {
@@ -126,9 +139,6 @@ pub fn apply_maven_cache(root: &Path, cache_dir: &Path, model: &mut MavenModel)
            p.dependencies = c.dependencies.clone();
        }
    }
-    model.synced_at = Some(cache.at_ms);
-    model.sync_error = cache.error;
-    model.stale = !cache.verbose || cache.hash != hash_files(&maven::build_files(root, model));
 }

 /// Merges the cached task list into `model`.
@@ -198,7 +208,8 @@ pub fn sync_maven(
    cancel: &CancellationToken,
    progress: &dyn Fn(SyncProgress),
 ) -> IdeResult<()> {
-    let model = maven::load(root);
+    let mut model = maven::load(root);
+    maven::UnlinkedProjects::from_model(&model, &options.maven_settings).filter(&mut model);
    std::fs::create_dir_all(cache_dir)?;
    let mut cache =
        MavenCache { hash: hash_files(&maven::build_files(root, &model)), verbose: true, ..MavenCache::default() };
@@ -266,7 +277,14 @@ pub fn sync_gradle(
        args.push("--offline".into());
    }
    progress(SyncProgress { message: "Loading Gradle tasks".into(), fraction: None });
-    let out = run(&model.command, &args, &root.join(&model.dir), &options.env, cancel, |_| {})?;
+    let out = run(
+        options.gradle_command.as_deref().unwrap_or(&model.command),
+        &args,
+        &root.join(&model.dir),
+        &options.env,
+        cancel,
+        |_| {},
+    )?;
    let cache = GradleCache {
        hash: hash_files(&gradle::build_files(root, &model)),
        at_ms: now_ms(),
@@ -280,6 +298,29 @@ pub fn sync_gradle(
 mod tests {
    use super::*;

+    #[cfg(unix)]
+    #[test]
+    fn gradle_sync_uses_resolved_command_and_environment() {
+        use std::os::unix::fs::PermissionsExt;
+        let tmp = tempfile::tempdir().unwrap();
+        let root = tmp.path();
+        std::fs::write(root.join("build.gradle"), "").unwrap();
+        let launcher = root.join("configured-gradle");
+        std::fs::write(&launcher, "#!/bin/sh\nprintf '%s\\n' \"$JAVA_HOME\" \"$GRADLE_USER_HOME\" > actual-env\n")
+            .unwrap();
+        std::fs::set_permissions(&launcher, std::fs::Permissions::from_mode(0o755)).unwrap();
+        let options = SyncOptions {
+            gradle_command: Some(launcher.to_string_lossy().into_owned()),
+            env: BTreeMap::from([
+                ("JAVA_HOME".into(), "/jdk21".into()),
+                ("GRADLE_USER_HOME".into(), "/gradle-cache".into()),
+            ]),
+            ..Default::default()
+        };
+        sync_gradle(root, &root.join("cache"), &options, &CancellationToken::new(), &|_| {}).unwrap();
+        assert_eq!(std::fs::read_to_string(root.join("actual-env")).unwrap(), "/jdk21\n/gradle-cache\n");
+    }
+
    #[test]
    fn caches_merge_and_go_stale() {
        let tmp = tempfile::tempdir().unwrap();
@@ -315,12 +356,16 @@ mod tests {

        std::fs::write(
            root.join("pom.xml"),
-            "<project><groupId>g</groupId><artifactId>a</artifactId><version>2</version></project>",
+            "<project><groupId>g</groupId><artifactId>a</artifactId><version>2</version>\
+             <dependencies><dependency><groupId>g</groupId><artifactId>fresh</artifactId><version>1</version></dependency></dependencies>\
+             </project>",
        )
        .unwrap();
        let mut model = maven::load_with_repo(&root, None);
        apply_maven_cache(&root, &cache_dir, &mut model);
        assert!(model.stale);
+        // The POM changed: the stale effective dependencies must not hide the new one (#249).
+        assert_eq!(model.projects[0].dependencies[0].artifact_id, "fresh");
    }

    #[test]
@@ -0,0 +1,268 @@
+//! WAR modules and build-tool-owned archive resolution (including custom output names).
+use crate::BuildModel;
+use ide_core::{CancellationToken, IdeError, IdeResult};
+use serde::{Deserialize, Serialize};
+use specta::Type;
+use std::{collections::BTreeMap, fs, path::Path};
+
+#[derive(Clone, Debug, Serialize, Deserialize, Type)]
+#[serde(rename_all = "camelCase")]
+pub struct WebArtifact {
+    pub id: String,
+    pub name: String,
+    pub module: String,
+    pub tool: String,
+}
+
+pub fn artifacts(root: &Path, model: &BuildModel) -> Vec<WebArtifact> {
+    let mut out = Vec::new();
+    if let Some(maven) = &model.maven {
+        for p in maven.projects.iter().filter(|p| p.packaging == "war") {
+            out.push(WebArtifact {
+                id: format!("maven:{}", p.pom),
+                name: p.artifact_id.clone(),
+                module: p.dir.clone(),
+                tool: "maven".into(),
+            });
+        }
+    }
+    if let Some(gradle) = &model.gradle {
+        for p in &gradle.projects {
+            let script = p.build_file.as_ref().and_then(|f| fs::read_to_string(root.join(f)).ok()).unwrap_or_default();
+            if p.tasks.iter().any(|t| t.name == "war") || crate::gradle::has_war_plugin(&script) {
+                out.push(WebArtifact {
+                    id: format!("gradle:{}", p.path),
+                    name: p.name.clone(),
+                    module: p.dir.clone(),
+                    tool: "gradle".into(),
+                });
+            }
+        }
+    }
+    out
+}
+
+pub struct WebBuild {
+    pub command: String,
+    pub args: Vec<String>,
+    pub cwd: String,
+    pub env: BTreeMap<String, String>,
+    maven_project: Option<(Vec<String>, std::path::PathBuf)>,
+}
+
+impl WebBuild {
+    /// Resolve the selected module's effective identity using the build's options and environment.
+    /// Runs off the UI thread, before launching the reactor build.
+    pub fn resolve_project(
+        &mut self,
+        root: &Path,
+        env: &BTreeMap<String, String>,
+        cancel: &CancellationToken,
+    ) -> IdeResult<()> {
+        let Some((args, output)) = &self.maven_project else {
+            return Ok(());
+        };
+        if output.exists() {
+            fs::remove_file(output)?;
+        }
+        let cwd = root.join(&self.cwd).canonicalize()?;
+        let mut env = env.clone();
+        if !env.iter().any(|(k, v)| k.eq_ignore_ascii_case("MAVEN_BASEDIR") && !v.is_empty()) {
+            // -f changes Maven's .mvn search origin; keep the reactor's launcher settings.
+            let base = cwd.ancestors().find(|p| p.join(".mvn").is_dir()).unwrap_or(&cwd);
+            env.retain(|k, _| !k.eq_ignore_ascii_case("MAVEN_BASEDIR"));
+            env.insert("MAVEN_BASEDIR".into(), base.to_string_lossy().into_owned());
+        }
+        let result = crate::process::run_with_env(&self.command, args, &cwd, &env, true, cancel, |_, _| {})?;
+        if !result.success {
+            return Err(IdeError::invalid(format!("Cannot resolve Maven WAR artifact: {}", result.text.trim())));
+        }
+        let id = fs::read_to_string(output)?;
+        let parts: Vec<_> = id.trim().split(':').collect();
+        if parts.len() != 4 || parts[2] != "war" || parts.iter().any(|s| s.is_empty()) {
+            return Err(IdeError::invalid(format!("Cannot resolve Maven WAR artifact: {}", id.trim())));
+        }
+        let project = format!("{}:{}:{}", parts[0], parts[1], parts[3]);
+        self.args.push(format!("-Dexpression=session.projectMap({project}).artifact.file"));
+        self.maven_project = None;
+        Ok(())
+    }
+}
+
+fn groovy_literal(s: &str) -> String {
+    format!("'{}'", s.replace('\\', "\\\\").replace('\'', "\\'"))
+}
+
+pub fn build(root: &Path, model: &BuildModel, id: &str, cache: &Path) -> IdeResult<WebBuild> {
+    fs::create_dir_all(cache)?;
+    let manifest = cache.join("artifact-path.txt");
+    // A failed build must never silently reuse an older archive manifest.
+    if manifest.exists() {
+        fs::remove_file(&manifest)?;
+    }
+    fs::write(cache.join("artifact-id.txt"), id)?;
+    if let Some(pom) = id.strip_prefix("maven:") {
+        let p = model
+            .maven
+            .as_ref()
+            .and_then(|m| m.projects.iter().find(|p| p.pom == pom && p.packaging == "war"))
+            .ok_or_else(|| IdeError::invalid("Choose a Maven WAR module"))?;
+        let projects = &model.maven.as_ref().unwrap().projects;
+        let top = projects
+            .iter()
+            .filter(|t| {
+                !t.aggregated && (t.dir.is_empty() || p.dir == t.dir || p.dir.starts_with(&format!("{}/", t.dir)))
+            })
+            .max_by_key(|t| t.dir.len())
+            .unwrap_or(p);
+        let mut args = top.options.clone();
+        if top.pom != p.pom {
+            let module = root
+                .join(&p.dir)
+                .strip_prefix(root.join(&top.dir))
+                .map_err(|e| IdeError::invalid(e.to_string()))?
+                .to_string_lossy()
+                .replace('\\', "/");
+            args.extend(["-pl".into(), module, "-am".into()]);
+        }
+        // help:evaluate runs once, in the reactor's first project. Query the selected
+        // POM's effective identity first; profiles and -D options can change its GAV.
+        let output = cache.join("artifact-project.txt");
+        let mut probe = top.options.clone();
+        probe.extend([
+            "-f".into(),
+            root.join(&p.pom).to_string_lossy().into_owned(),
+            "help:evaluate".into(),
+            "-Dexpression=project.id".into(),
+            format!("-Doutput={}", output.display()),
+        ]);
+        args.extend([
+            "-DskipTests".into(),
+            "package".into(),
+            "help:evaluate".into(),
+            format!("-Doutput={}", manifest.display()),
+        ]);
+        return Ok(WebBuild {
+            command: top.command.clone(),
+            args,
+            cwd: top.dir.clone(),
+            env: p.env.clone(),
+            maven_project: Some((probe, output)),
+        });
+    }
+    if let Some(path) = id.strip_prefix("gradle:") {
+        let g = model.gradle.as_ref().ok_or_else(|| IdeError::invalid("Choose a Gradle WAR module"))?;
+        if !artifacts(root, model).iter().any(|a| a.id == id) {
+            return Err(IdeError::invalid("Choose a Gradle WAR module"));
+        }
+        let script = cache.join("war.init.gradle");
+        fs::write(
+            &script,
+            format!(
+                r#"gradle.projectsEvaluated {{
+    def p = gradle.rootProject.project({})
+    def warTask = p.tasks.named('war')
+    p.tasks.register('openideaTomcatArtifact') {{
+        dependsOn warTask
+        doLast {{ new File({}).setText(warTask.get().archiveFile.get().asFile.absolutePath, 'UTF-8') }}
+    }}
+}}
+"#,
+                groovy_literal(path),
+                groovy_literal(&manifest.to_string_lossy())
+            ),
+        )?;
+        let task = format!("{}:openideaTomcatArtifact", path.trim_end_matches(':'));
+        return Ok(WebBuild {
+            command: g.command.clone(),
+            args: vec!["--init-script".into(), script.to_string_lossy().into_owned(), task],
+            cwd: g.dir.clone(),
+            env: g.env.clone(),
+            maven_project: None,
+        });
+    }
+    Err(IdeError::invalid("Choose a WAR artifact"))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn maven_war_modules_use_resolved_artifact_file() {
+        let tmp = tempfile::tempdir().unwrap();
+        fs::write(tmp.path().join("pom.xml"), "<project><modelVersion>4.0.0</modelVersion><groupId>test</groupId><artifactId>web</artifactId><version>1</version><packaging>war</packaging><build><directory>custom</directory><finalName>renamed</finalName></build></project>").unwrap();
+        let model = crate::load(tmp.path(), &tmp.path().join("cache"), None);
+        let a = artifacts(tmp.path(), &model);
+        assert_eq!(a.len(), 1);
+        assert_eq!(a[0].name, "web");
+        let plan = build(tmp.path(), &model, &a[0].id, &tmp.path().join("base with spaces")).unwrap();
+        let (probe, _) = plan.maven_project.as_ref().unwrap();
+        assert!(probe.contains(&"-Dexpression=project.id".into()));
+        assert!(probe.contains(&tmp.path().join("pom.xml").to_string_lossy().into_owned()));
+        assert!(
+            plan.args.iter().any(|a| a.ends_with("base with spaces/artifact-path.txt")
+                || a.ends_with("base with spaces\\artifact-path.txt"))
+        );
+    }
+    #[test]
+    fn maven_module_build_includes_reactor_dependencies() {
+        let tmp = tempfile::tempdir().unwrap();
+        fs::create_dir_all(tmp.path().join("web")).unwrap();
+        fs::write(tmp.path().join("pom.xml"), "<project><groupId>test</groupId><artifactId>parent</artifactId><version>1</version><packaging>pom</packaging><modules><module>web</module></modules></project>").unwrap();
+        fs::write(tmp.path().join("web/pom.xml"), "<project><parent><groupId>test</groupId><artifactId>parent</artifactId><version>1</version></parent><artifactId>web</artifactId><packaging>war</packaging></project>").unwrap();
+        let model = crate::load(tmp.path(), &tmp.path().join("cache"), None);
+        let plan = build(tmp.path(), &model, "maven:web/pom.xml", &tmp.path().join("base")).unwrap();
+        assert_eq!(plan.cwd, "");
+        assert_eq!(&plan.args[..3], &["-pl", "web", "-am"]);
+        assert!(
+            plan.maven_project
+                .as_ref()
+                .unwrap()
+                .0
+                .contains(&tmp.path().join("web/pom.xml").to_string_lossy().into_owned())
+        );
+    }
+    #[test]
+    fn gradle_war_uses_archive_provider_and_ignores_comments() {
+        let tmp = tempfile::tempdir().unwrap();
+        fs::write(
+            tmp.path().join("build.gradle.kts"),
+            "plugins { war }\ntasks.war { archiveFileName.set(\"custom.war\") }",
+        )
+        .unwrap();
+        let model = crate::load(tmp.path(), &tmp.path().join("cache"), None);
+        let a = artifacts(tmp.path(), &model);
+        assert_eq!(a.len(), 1);
+        let plan = build(tmp.path(), &model, &a[0].id, &tmp.path().join("base")).unwrap();
+        assert!(plan.args.contains(&":openideaTomcatArtifact".into()));
+        assert!(fs::read_to_string(tmp.path().join("base/war.init.gradle")).unwrap().contains("archiveFile.get()"));
+        assert!(!crate::gradle::has_war_plugin("// plugins { war }"));
+    }
+
+    #[test]
+    fn gradle_manifest_paths_preserve_windows_characters() {
+        for path in [r"C:\工作 区\Tomcat's cache\artifact-path.txt", r"\\server\share\artifact-path.txt"] {
+            let literal = groovy_literal(path);
+            assert_eq!(literal[1..literal.len() - 1].replace("\\'", "'").replace("\\\\", "\\"), path);
+        }
+    }
+
+    #[test]
+    fn gradle_root_and_nested_modules_write_utf8_archive_paths() {
+        for module in [":", ":apps:timesheet"] {
+            let tmp = tempfile::tempdir().unwrap();
+            let dir = if module == ":" { "" } else { "apps/timesheet" };
+            fs::create_dir_all(tmp.path().join(dir)).unwrap();
+            fs::write(tmp.path().join("settings.gradle"), "rootProject.name = 'timesheet'\ninclude 'apps:timesheet'")
+                .unwrap();
+            fs::write(tmp.path().join(dir).join("build.gradle"), "plugins { id 'war' }").unwrap();
+            let model = crate::load(tmp.path(), &tmp.path().join("cache"), None);
+            let cache = tmp.path().join("工作 cache");
+            let plan = build(tmp.path(), &model, &format!("gradle:{module}"), &cache).unwrap();
+            assert!(plan.args.contains(&format!("{}:openideaTomcatArtifact", module.trim_end_matches(':'))));
+            let script = fs::read_to_string(cache.join("war.init.gradle")).unwrap();
+            assert!(script.contains(&format!("rootProject.project('{}')", module)));
+            assert!(script.contains("archiveFile.get().asFile.absolutePath, 'UTF-8'"));
+        }
+    }
+}
@@ -1,6 +1,8 @@
 //! The file list on the OS clipboard: what Explorer copies when the user
 //! copies files, so the project view can paste them, and what the project view
-//! writes so Explorer can paste the files it copied (IDEA does both).
+//! writes so Explorer can paste the files it copied (IDEA does both). The
+//! written list comes with the paths as text, so a paste into an editor
+//! inserts them instead of doing nothing.
 //!
 //! Windows keeps it as `CF_HDROP`: a `DROPFILES` header and a double-NUL
 //! terminated list of absolute paths, wide when `fWide` is set. The data is set
@@ -10,6 +12,9 @@
 //! macOS keeps one `public.file-url` item per file on the general
 //! `NSPasteboard`; `NSURL` reads and writes them, so Finder's copies paste here
 //! and ours paste in Finder.
+//! On macOS, [`files`], [`has_files`] and [`set_files`] must run on the main
+//! thread: AppKit and WebKit also access the general pasteboard there, and its
+//! mutable type cache cannot be protected by a mutex in this crate.
 //!
 //! Other platforms (`text/uri-list` on X11) are not wired up: [`files`] is
 //! empty and [`set_files`] fails there.
@@ -20,7 +25,8 @@ use std::path::PathBuf;
 const HEADER: usize = 20;

 /// The absolute paths on the clipboard, empty when it holds no file list.
-pub fn files() -> Vec<PathBuf> {
+/// Read failures remain errors so callers can retain an internal copy.
+pub fn files() -> std::io::Result<Vec<PathBuf>> {
    imp::files()
 }

@@ -29,9 +35,8 @@ pub fn has_files() -> bool {
    imp::has_files()
 }

-/// Replaces the clipboard with `paths`. False when it is busy or holds nothing
-/// to write; the clipboard is a shared resource, so callers treat this as
-/// best-effort.
+/// Replaces the clipboard with `paths`. True only when the file list was
+/// accepted; writing just the accompanying text is not a successful hand-off.
 pub fn set_files(paths: &[PathBuf]) -> bool {
    if paths.is_empty() {
        return false;
@@ -111,6 +116,8 @@ mod imp {

    /// `CF_HDROP`, the clipboard format holding a file list.
    const CF_HDROP: u32 = 15;
+    /// `CF_UNICODETEXT`, so an editor paste of copied files inserts the paths.
+    const CF_UNICODETEXT: u32 = 13;

    /// An `HGLOBAL` or a `HANDLE`: both are opaque pointers here.
    type Handle = *mut c_void;
@@ -156,25 +163,29 @@ mod imp {
        (unsafe { IsClipboardFormatAvailable(CF_HDROP) }) != 0
    }

-    pub fn files() -> Vec<PathBuf> {
-        if !has_files() || !open() {
-            return Vec::new();
+    pub fn files() -> std::io::Result<Vec<PathBuf>> {
+        if !open() {
+            return Err(std::io::Error::last_os_error());
+        }
+        if !has_files() {
+            unsafe { CloseClipboard() };
+            return Ok(Vec::new());
        }
        let memory = unsafe { GetClipboardData(CF_HDROP) };
        let paths = if memory.is_null() {
-            Vec::new()
+            Err(std::io::Error::last_os_error())
        } else {
            // SAFETY: the clipboard keeps the block alive while it is open, and
            // `GlobalSize` bounds the bytes read from it.
            unsafe {
                let data = GlobalLock(memory);
                if data.is_null() {
-                    Vec::new()
+                    Err(std::io::Error::last_os_error())
                } else {
                    let bytes = std::slice::from_raw_parts(data as *const u8, GlobalSize(memory));
                    let paths = decode(bytes);
                    GlobalUnlock(memory);
-                    paths
+                    Ok(paths)
                }
            }
        };
@@ -182,12 +193,37 @@ mod imp {
        paths
    }

+    /// An `HGLOBAL` holding `text` as UTF-16 with a terminating NUL, and its
+    /// byte size. Null when the allocation failed.
+    fn global_text(text: &str) -> (Handle, usize) {
+        let mut units: Vec<u16> = text.encode_utf16().collect();
+        units.push(0);
+        let bytes = units.len() * 2;
+        unsafe {
+            let memory = GlobalAlloc(GMEM_MOVEABLE, bytes);
+            if memory.is_null() {
+                return (ptr::null_mut(), 0);
+            }
+            let data = GlobalLock(memory);
+            if data.is_null() {
+                GlobalFree(memory);
+                return (ptr::null_mut(), 0);
+            }
+            ptr::copy_nonoverlapping(units.as_ptr() as *const u8, data as *mut u8, bytes);
+            GlobalUnlock(memory);
+            (memory, bytes)
+        }
+    }
+
    pub fn set_files(paths: &[PathBuf]) -> bool {
        let bytes = encode(paths);
        if bytes.len() <= HEADER {
            return false;
        }
-        // SAFETY: the block is allocated, filled, handed to the clipboard and
+        // The paths as text, newline-separated, so pasting into an editor
+        // inserts them (IDEA writes the list and the text together).
+        let text = paths.iter().map(|p| p.to_string_lossy().into_owned()).collect::<Vec<_>>().join("\r\n");
+        // SAFETY: the blocks are allocated, filled, handed to the clipboard and
        // freed only on the paths where the clipboard did not take ownership.
        unsafe {
            let memory = GlobalAlloc(GMEM_MOVEABLE, bytes.len());
@@ -205,17 +241,26 @@ mod imp {
                GlobalFree(memory);
                return false;
            }
-            // Replacing the list also drops the text the user copied before.
+            // Replacing the list also drops the text the user copied before;
+            // the paths' own text is set back with it.
            if EmptyClipboard() == 0 {
                CloseClipboard();
                GlobalFree(memory);
                return false;
            }
            let taken = !SetClipboardData(CF_HDROP, memory).is_null();
-            CloseClipboard();
            if !taken {
                GlobalFree(memory);
            }
+            let (text_memory, _) = global_text(&text);
+            if !text_memory.is_null() {
+                // The text alone still pastes somewhere useful.
+                let text_taken = !SetClipboardData(CF_UNICODETEXT, text_memory).is_null();
+                if !text_taken {
+                    GlobalFree(text_memory);
+                }
+            }
+            CloseClipboard();
            taken
        }
    }
@@ -223,13 +268,14 @@ mod imp {

 #[cfg(target_os = "macos")]
 mod imp {
-    use objc2::ClassType;
    use objc2::rc::{Retained, autoreleasepool};
    use objc2::runtime::{AnyClass, AnyObject, ProtocolObject};
+    use objc2::{ClassType, MainThreadMarker};
    use objc2_app_kit::{
-        NSPasteboard, NSPasteboardReadingOptionKey, NSPasteboardURLReadingFileURLsOnlyKey, NSPasteboardWriting,
+        NSPasteboard, NSPasteboardReadingOptionKey, NSPasteboardTypeString, NSPasteboardURLReadingFileURLsOnlyKey,
+        NSPasteboardWriting,
    };
-    use objc2_foundation::{NSArray, NSDictionary, NSNumber, NSURL};
+    use objc2_foundation::{NSArray, NSDictionary, NSNumber, NSString, NSURL};
    use std::path::PathBuf;

    /// `NSURL` as the one class to read, limited to file URLs: a web link the
@@ -237,6 +283,7 @@ mod imp {
    fn read_file_urls<R>(
        f: impl FnOnce(&NSPasteboard, &NSArray<AnyClass>, &NSDictionary<NSPasteboardReadingOptionKey, AnyObject>) -> R,
    ) -> R {
+        debug_assert!(MainThreadMarker::new().is_some(), "NSPasteboard access requires the main thread");
        autoreleasepool(|_| {
            let board = NSPasteboard::generalPasteboard();
            let classes = NSArray::from_slice(&[NSURL::class()]);
@@ -256,23 +303,28 @@ mod imp {
        })
    }

-    pub fn files() -> Vec<PathBuf> {
+    pub fn files() -> std::io::Result<Vec<PathBuf>> {
        read_file_urls(|board, classes, options| {
            // SAFETY: as in `has_files`; every object read for `NSURL` is one.
            let Some(objects) = (unsafe { board.readObjectsForClasses_options(classes, Some(options)) }) else {
-                return Vec::new();
+                return if unsafe { board.canReadObjectForClasses_options(classes, Some(options)) } {
+                    Err(std::io::Error::other("Cannot read clipboard files"))
+                } else {
+                    Ok(Vec::new())
+                };
            };
-            objects
+            Ok(objects
                .iter()
                .filter_map(|object| object.downcast::<NSURL>().ok())
                .filter_map(|url| url.to_file_path())
                // Finder ends a folder's URL in `/`; the project view names it without.
                .map(|path| path.components().collect())
-                .collect()
+                .collect())
        })
    }

    pub fn set_files(paths: &[PathBuf]) -> bool {
+        debug_assert!(MainThreadMarker::new().is_some(), "NSPasteboard access requires the main thread");
        autoreleasepool(|_| {
            // Folders get a directory URL (ending in `/`), as Finder writes them.
            let urls: Vec<Retained<NSURL>> = paths
@@ -285,9 +337,16 @@ mod imp {
            let writers: Vec<&ProtocolObject<dyn NSPasteboardWriting>> =
                urls.iter().map(|url| ProtocolObject::from_ref(&**url)).collect();
            let board = NSPasteboard::generalPasteboard();
-            // Replacing the list also drops the text the user copied before.
+            // Replacing the list also drops the text the user copied before;
+            // the paths' own text is set back with it, so an editor paste
+            // inserts them (IDEA writes the list and the text together).
            board.clearContents();
-            board.writeObjects(&NSArray::from_slice(&writers))
+            let written = board.writeObjects(&NSArray::from_slice(&writers));
+            let text = NSString::from_str(
+                &paths.iter().map(|p| p.to_string_lossy().into_owned()).collect::<Vec<_>>().join("\n"),
+            );
+            board.setString_forType(&text, unsafe { NSPasteboardTypeString });
+            written
        })
    }
 }
@@ -300,8 +359,8 @@ mod imp {
        false
    }

-    pub fn files() -> Vec<PathBuf> {
-        Vec::new()
+    pub fn files() -> std::io::Result<Vec<PathBuf>> {
+        Ok(Vec::new())
    }

    pub fn set_files(_paths: &[PathBuf]) -> bool {
@@ -7,6 +7,7 @@ license.workspace = true

 [dependencies]
 dunce.workspace = true
+encoding_rs.workspace = true
 serde.workspace = true
 serde_json.workspace = true
 specta.workspace = true
@@ -16,3 +17,6 @@ tokio-util.workspace = true

 [dev-dependencies]
 tempfile.workspace = true
+
+[target.'cfg(windows)'.dependencies]
+windows-sys = { version = "0.61", features = ["Win32_Globalization", "Win32_System_Registry", "Win32_Foundation"] }
@@ -12,6 +12,8 @@ use std::collections::BTreeMap;
 pub struct EditorGeneralSettings {
    /// Change font size with ⌘ + mouse wheel.
    pub wheel_zoom: bool,
+    pub markdown_image_folder: String,
+    pub markdown_image_name_pattern: String,
    /// Drag-and-drop of selected text inside the editor.
    pub drag_and_drop: bool,
    /// When the caret moves out of view: `minimize` scrolling | `center` the caret line.
@@ -35,6 +37,8 @@ impl Default for EditorGeneralSettings {
    fn default() -> Self {
        Self {
            wheel_zoom: false,
+            markdown_image_folder: "assets".into(),
+            markdown_image_name_pattern: "image-{timestamp}".into(),
            drag_and_drop: true,
            caret_scroll: "minimize".into(),
            soft_wrap_files: "*.md; *.txt; *.rst; *.adoc".into(),
@@ -367,6 +371,12 @@ pub struct TextAttributesOverride {
 #[derive(Clone, Debug, Default, PartialEq, Serialize, Deserialize, Type)]
 #[serde(default, rename_all = "camelCase")]
 pub struct LanguageCodeStyle {
+    /// Java formatter: `default` | `intellij` | `custom` (other languages ignore it).
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub formatter: Option<String>,
+    /// Eclipse formatter XML; relative paths start at the project root.
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub formatter_path: Option<String>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub use_tab: Option<bool>,
    #[serde(skip_serializing_if = "Option::is_none")]
@@ -434,6 +444,8 @@ pub struct EncodingSettings {
    pub project: String,
    /// Fallback for `.properties` files.
    pub properties: String,
+    /// Display properties Unicode escapes as characters and save non-ASCII as escapes.
+    pub native_to_ascii: bool,
    /// Create UTF-8 files: `never` (no BOM) | `always` (with BOM) | `windows` (with BOM on Windows).
    pub utf8_bom: String,
 }
@@ -444,6 +456,7 @@ impl Default for EncodingSettings {
            global: "utf-8".into(),
            project: "utf-8".into(),
            properties: "iso-8859-1".into(),
+            native_to_ascii: false,
            utf8_bom: "never".into(),
        }
    }
@@ -12,6 +12,15 @@ pub type IdeResult<T> = Result<T, IdeError>;
 pub struct IdeError {
    pub kind: ErrorKind,
    pub message: String,
+    /// Structured detail for errors the UI acts on; `null` for plain errors.
+    #[specta(optional)]
+    pub data: Option<ErrorData>,
+}
+
+#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize, Type)]
+#[serde(tag = "type", rename_all = "camelCase")]
+pub enum ErrorData {
+    Tool { tool: String, missing: bool },
 }

 #[derive(Clone, Copy, Debug, PartialEq, Eq, Serialize, Deserialize, Type)]
@@ -24,6 +33,7 @@ pub enum ErrorKind {
    /// Document version mismatch; the UI must resync the full text.
    OutOfSync,
    Cancelled,
+    TimedOut,
    /// A required external tool (language server, git, debugger) is unavailable.
    Unavailable,
    Io,
@@ -33,7 +43,21 @@ pub enum ErrorKind {

 impl IdeError {
    pub fn new(kind: ErrorKind, message: impl Into<String>) -> Self {
-        Self { kind, message: message.into() }
+        Self { kind, message: message.into(), data: None }
+    }
+    pub fn with_tool(mut self, tool: impl Into<String>) -> Self {
+        if self.data.is_none() {
+            self.data = Some(ErrorData::Tool { tool: tool.into(), missing: false });
+        }
+        self
+    }
+    pub fn missing_tool(tool: impl Into<String>) -> Self {
+        let tool = tool.into();
+        Self {
+            kind: ErrorKind::NotFound,
+            message: format!("{tool} is not installed"),
+            data: Some(ErrorData::Tool { tool, missing: true }),
+        }
    }
    pub fn not_found(m: impl Into<String>) -> Self {
        Self::new(ErrorKind::NotFound, m)
@@ -65,3 +89,30 @@ impl From<std::io::Error> for IdeError {
        Self::new(kind, e.to_string())
    }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn tool_errors_round_trip_without_changing_diagnostics() {
+        let message = "[error] file.css: Unexpected token\n  1 | }\n";
+        let error = IdeError::invalid(message).with_tool("prettier");
+        let decoded: IdeError = serde_json::from_str(&serde_json::to_string(&error).unwrap()).unwrap();
+        assert_eq!(decoded.message, message);
+        assert_eq!(decoded.data, Some(ErrorData::Tool { tool: "prettier".into(), missing: false }));
+        let missing = IdeError::missing_tool("prettier").with_tool("prettier");
+        assert_eq!(missing.kind, ErrorKind::NotFound);
+        assert_eq!(missing.data, Some(ErrorData::Tool { tool: "prettier".into(), missing: true }));
+    }
+
+    #[test]
+    fn legacy_errors_need_no_data() {
+        let error: IdeError = serde_json::from_str(r#"{"kind":"unavailable","message":"no server"}"#).unwrap();
+        assert!(error.data.is_none());
+        assert_eq!(
+            serde_json::to_value(error).unwrap(),
+            serde_json::json!({"kind":"unavailable","message":"no server","data":null})
+        );
+    }
+}
@@ -13,12 +13,22 @@ use std::sync::Arc;
 #[derive(Clone, Debug, Serialize, Deserialize, Type)]
 #[serde(tag = "type", rename_all = "camelCase", rename_all_fields = "camelCase")]
 pub enum IdeEvent {
+    /// Project window membership or selection changed.
+    WindowGroupsChanged,
+    ProjectTrustChanged {
+        root: crate::IpcPath,
+        trusted: bool,
+    },
    /// Files or directories changed on disk (after debouncing, ignore rules applied).
    FsChanged {
        created: Vec<crate::IpcPath>,
        modified: Vec<crate::IpcPath>,
        removed: Vec<crate::IpcPath>,
    },
+    /// Excluded or ignored folders whose contents changed; they stay out of `FsChanged`.
+    ExcludedDirsChanged {
+        dirs: Vec<crate::IpcPath>,
+    },
    /// The backend changed a document (reload from disk, formatting, refactoring).
    /// The UI applies `changes` on top of `base_version`, yielding `version`.
    DocPatched {
@@ -32,10 +42,13 @@ pub enum IdeEvent {
        doc: DocId,
        dirty: bool,
    },
-    /// An open document's language changed (Settings › File Types, Override File Type).
+    /// An open document's language changed (Settings › File Types, Override File
+    /// Type), or its UI mode (a framework's root marker appeared or went).
    DocLanguage {
        doc: DocId,
        language: crate::LanguageId,
+        /// See `DocumentInfo::ui_mode`.
+        ui_mode: Option<String>,
    },
    /// Full replacement of diagnostics for one file from one producer.
    Diagnostics {
@@ -112,11 +125,22 @@ pub enum IdeEvent {
        id: u64,
        prompt: String,
        kind: AskpassKind,
+        /// The dialog offers "Remember" for the answer (git HTTPS passwords).
+        remember: bool,
    },
    /// Prompt `id` was answered (in any window) or gave up.
    AskpassDone {
        id: u64,
    },
+    /// The kernel of an open notebook changed state (`starting`, `idle`, `busy`,
+    /// `dead`); `message` says why it failed to start or died.
+    NotebookKernel {
+        /// Backend document incarnation; stale queued events cannot target a reopen.
+        id: String,
+        path: crate::IpcPath,
+        state: String,
+        message: Option<String>,
+    },
 }

 /// What an askpass prompt asks for.
@@ -20,6 +20,7 @@ pub mod remote_settings;
 pub mod settings;
 pub mod task;
 pub mod text;
+pub mod tool_path;
 pub mod version_managers;
 pub mod workflow_settings;

@@ -18,6 +18,60 @@

 use std::collections::BTreeMap;

+/// Decodes complete lines or collected output from IDE-managed tools, preferring UTF-8.
+/// Windows launcher/native diagnostics fall back to the system ANSI code page.
+/// Callers must buffer incomplete lines so multibyte characters are never split.
+/// Run consoles and protocol streams have their own encoding contracts.
+pub fn decode_tool_output(bytes: &[u8]) -> String {
+    #[cfg(windows)]
+    // SAFETY: GetACP is an argument-less query with no preconditions.
+    let code_page = unsafe { windows_sys::Win32::Globalization::GetACP() };
+    #[cfg(not(windows))]
+    let code_page = 65001;
+    decode_tool_output_with_code_page(bytes, code_page)
+}
+
+fn decode_tool_output_with_code_page(bytes: &[u8], code_page: u32) -> String {
+    if let Ok(text) = std::str::from_utf8(bytes) {
+        return text.to_owned();
+    }
+    let encoding = encoding_for_code_page(code_page).unwrap_or(encoding_rs::UTF_8);
+    // Collected output can mix UTF-8 JVM lines with native launcher diagnostics.
+    let mut text = String::new();
+    for line in bytes.split_inclusive(|b| *b == b'\n') {
+        match std::str::from_utf8(line) {
+            Ok(line) => text.push_str(line),
+            Err(_) => text.push_str(&encoding.decode_without_bom_handling(line).0),
+        }
+    }
+    text
+}
+
+fn encoding_for_code_page(cp: u32) -> Option<&'static encoding_rs::Encoding> {
+    Some(match cp {
+        65001 => encoding_rs::UTF_8,
+        936 => encoding_rs::GBK,
+        54936 => encoding_rs::GB18030,
+        950 => encoding_rs::BIG5,
+        932 => encoding_rs::SHIFT_JIS,
+        949 => encoding_rs::EUC_KR,
+        866 => encoding_rs::IBM866,
+        874 => encoding_rs::WINDOWS_874,
+        1250 => encoding_rs::WINDOWS_1250,
+        1251 => encoding_rs::WINDOWS_1251,
+        1252 => encoding_rs::WINDOWS_1252,
+        1253 => encoding_rs::WINDOWS_1253,
+        1254 => encoding_rs::WINDOWS_1254,
+        1255 => encoding_rs::WINDOWS_1255,
+        1256 => encoding_rs::WINDOWS_1256,
+        1257 => encoding_rs::WINDOWS_1257,
+        1258 => encoding_rs::WINDOWS_1258,
+        20866 => encoding_rs::KOI8_R,
+        21866 => encoding_rs::KOI8_U,
+        _ => return None,
+    })
+}
+
 const STD_PROPERTIES: &[&str] = &["stdout.encoding", "stderr.encoding", "sun.stdout.encoding", "sun.stderr.encoding"];
 const FILE_ENCODING: &str = "file.encoding";
 const TOOL_OPTIONS: &str = "JAVA_TOOL_OPTIONS";
@@ -161,13 +215,21 @@ fn fix_kind(
 }

 /// `vmArgs` of a launch by java-debug, which decodes the JVM's output as `encoding`
-/// (its launch attribute, UTF-8 when unset) and sets `file.encoding` itself.
-pub fn java_debug_vm_args(vm_args: &str, encoding: Option<&str>, windows: bool) -> Option<String> {
+/// (its launch attribute, UTF-8 when unset). java-debug sets `file.encoding` only
+/// when that attribute is nonblank; use the same defaults and user overrides as [`fix`].
+pub fn java_debug_vm_args(
+    vm_args: &str,
+    vars: &BTreeMap<String, String>,
+    inherited: impl Fn(&str) -> Option<String>,
+    encoding: Option<&str>,
+    windows: bool,
+) -> Option<String> {
    let encoding = encoding.map(str::trim).filter(|e| !e.is_empty()).unwrap_or("UTF-8");
-    if (!windows && is_utf8(encoding)) || sets(vm_args, STD_PROPERTIES) {
+    let added = fix_kind(Kind::Java, Some(&[vm_args.to_owned()]), vars, inherited, encoding, windows).java_args;
+    if added.is_empty() {
        return None;
    }
-    let added = options(STD_PROPERTIES, encoding).join(" ");
+    let added = added.join(" ");
    Some(match vm_args.trim() {
        "" => added,
        own => format!("{own} {added}"),
@@ -237,6 +299,29 @@ impl NoticeFilter {
 mod tests {
    use super::*;

+    #[test]
+    fn tool_output_prefers_utf8() {
+        for cp in [936, 1252, 65001, 0] {
+            for text in ["", "plain ASCII\r\n", "中文 café 🦀\n"] {
+                assert_eq!(decode_tool_output_with_code_page(text.as_bytes(), cp), text);
+            }
+        }
+    }
+
+    #[test]
+    fn tool_output_decodes_native_diagnostics_and_mixed_lines() {
+        const GBK: &[u8] = b"\xcf\xb5\xcd\xb3\xd5\xd2\xb2\xbb\xb5\xbd\xd6\xb8\xb6\xa8\xb5\xc4\xc2\xb7\xbe\xb6\xa1\xa3";
+        assert_eq!(decode_tool_output_with_code_page(GBK, 936), "系统找不到指定的路径。");
+        let mut mixed = "JVM: 中文\r\n".as_bytes().to_vec();
+        mixed.extend_from_slice(GBK);
+        mixed.extend_from_slice(b"\r\nlast");
+        assert_eq!(decode_tool_output_with_code_page(&mixed, 936), "JVM: 中文\r\n系统找不到指定的路径。\r\nlast");
+        assert_eq!(decode_tool_output_with_code_page(b"caf\xe9", 1252), "café");
+        for cp in [65001, 0] {
+            assert_eq!(decode_tool_output_with_code_page(b"a\xffb", cp), "a�b");
+        }
+    }
+
    const STD_UTF8: [&str; 4] = [
        "-Dstdout.encoding=UTF-8",
        "-Dstderr.encoding=UTF-8",
@@ -369,12 +454,53 @@ mod tests {

    #[test]
    fn java_debug_launches_write_what_java_debug_decodes() {
-        assert_eq!(java_debug_vm_args("", None, true).as_deref(), Some(TOOL_UTF8));
-        assert_eq!(java_debug_vm_args("-Xmx1g", Some(""), true), Some(format!("-Xmx1g {TOOL_UTF8}")));
-        assert_eq!(java_debug_vm_args("", Some("GBK"), true).unwrap().split(' ').next(), Some("-Dstdout.encoding=GBK"));
-        assert_eq!(java_debug_vm_args("-Dstdout.encoding=GBK", None, true), None);
-        assert_eq!(java_debug_vm_args("-Xmx1g", None, false), None);
-        assert!(java_debug_vm_args("", Some("GBK"), false).is_some());
+        let debug =
+            |args: &str, encoding, windows| java_debug_vm_args(args, &BTreeMap::new(), |_| None, encoding, windows);
+        for encoding in [None, Some(""), Some("  "), Some("UTF-8"), Some("utf8")] {
+            let streams = encoding.filter(|e| !e.trim().is_empty()).unwrap_or("UTF-8");
+            let utf8 = format!("{} -Dfile.encoding=UTF-8", options(STD_PROPERTIES, streams).join(" "));
+            assert_eq!(debug("", encoding, true), Some(utf8.clone()));
+            assert_eq!(debug("-Xmx1g", encoding, true), Some(format!("-Xmx1g {utf8}")));
+            assert_eq!(debug("-Xmx1g", encoding, false), None);
+        }
+        for windows in [true, false] {
+            assert_eq!(debug("", Some("GBK"), windows), Some(options(STD_PROPERTIES, "GBK").join(" ")));
+        }
+    }
+
+    #[test]
+    fn java_debug_preserves_user_options_independently() {
+        let debug = |args: &str| java_debug_vm_args(args, &BTreeMap::new(), |_| None, None, true);
+        assert_eq!(debug("-Dfile.encoding=GBK"), Some(format!("-Dfile.encoding=GBK {TOOL_UTF8}")));
+        for property in STD_PROPERTIES {
+            let args = format!("-D{property}=GBK");
+            assert_eq!(debug(&args), Some(format!("{args} -Dfile.encoding=UTF-8")));
+            assert_eq!(debug(&format!("{args} -Dfile.encoding=GBK")), None);
+        }
+        for key in ["JDK_JAVA_OPTIONS", TOOL_OPTIONS] {
+            for (own, expected) in [
+                ("-Dfile.encoding=GBK", Some(TOOL_UTF8.to_owned())),
+                ("-Dstdout.encoding=GBK", Some("-Dfile.encoding=UTF-8".to_owned())),
+                ("-Dstdout.encoding=GBK -Dfile.encoding=GBK", None),
+            ] {
+                assert_eq!(java_debug_vm_args("", &vars(&[(key, own)]), |_| None, None, true), expected);
+                assert_eq!(
+                    java_debug_vm_args("", &BTreeMap::new(), |k| (k == key).then(|| own.to_owned()), None, true),
+                    expected
+                );
+            }
+            // A launch environment value overrides the inherited one, as in Run.
+            assert_eq!(
+                java_debug_vm_args(
+                    "",
+                    &vars(&[(key, "")]),
+                    |k| (k == key).then(|| "-Dfile.encoding=GBK".into()),
+                    None,
+                    true
+                ),
+                Some(format!("{TOOL_UTF8} -Dfile.encoding=UTF-8"))
+            );
+        }
    }

    fn filtered(chunks: &[&str]) -> String {
@@ -218,10 +218,129 @@ pub fn executable_names(name: &str, windows: bool, pathext: Option<&str>) -> Vec
    exts.iter().map(|e| format!("{name}{}", e.to_ascii_lowercase())).collect()
 }

+/// First `search` directory holding `name` (see [`executable_names`]).
+pub fn find_executable_in(
+    name: &str,
+    search: &OsStr,
+    windows: bool,
+    pathext: Option<&str>,
+) -> Option<std::path::PathBuf> {
+    let names = executable_names(name, windows, pathext);
+    std::env::split_paths(search)
+        .filter(|d| !d.as_os_str().is_empty())
+        .find_map(|dir| names.iter().map(|n| dir.join(n)).find(|p| p.is_file()))
+}
+
+/// [`find_executable_in`] for this platform (`PATHEXT` from the environment).
+pub fn find_executable(name: &str, search: &OsStr) -> Option<std::path::PathBuf> {
+    let pathext = host_var_os("PATHEXT");
+    find_executable_in(name, search, cfg!(windows), pathext.as_deref().and_then(|p| p.to_str()))
+}
+
+/// The user's own `PATH` entries on Windows (`HKCU\Environment`), the part of the
+/// merged `PATH` a process may not inherit — an IDE started before the variable was
+/// edited, or as a different user, sees only the machine entries. `%VAR%` references
+/// (`REG_EXPAND_SZ`) are expanded against the current environment. `None` elsewhere:
+/// there a login shell already supplies the user's whole `PATH`.
+#[cfg(windows)]
+pub fn user_path() -> Option<OsString> {
+    use windows_sys::Win32::Foundation::ERROR_SUCCESS;
+    use windows_sys::Win32::System::Registry::{
+        HKEY, HKEY_CURRENT_USER, KEY_READ, RRF_RT_REG_EXPAND_SZ, RRF_RT_REG_SZ, RegCloseKey, RegGetValueW,
+        RegOpenKeyExW,
+    };
+
+    fn wide(s: &str) -> Vec<u16> {
+        s.encode_utf16().chain(std::iter::once(0)).collect()
+    }
+
+    unsafe {
+        let mut key: HKEY = std::ptr::null_mut();
+        if RegOpenKeyExW(HKEY_CURRENT_USER, wide("Environment").as_ptr(), 0, KEY_READ, &mut key) != ERROR_SUCCESS {
+            return None;
+        }
+        let read = || {
+            // Only `Path`; `REG_EXPAND_SZ` is accepted so `%USERPROFILE%\…` entries expand.
+            let mut kind = 0u32;
+            let mut len = 0u32;
+            let name = wide("Path");
+            let status = RegGetValueW(
+                key,
+                std::ptr::null(),
+                name.as_ptr(),
+                RRF_RT_REG_SZ | RRF_RT_REG_EXPAND_SZ,
+                &mut kind,
+                std::ptr::null_mut(),
+                &mut len,
+            );
+            if status != ERROR_SUCCESS || len == 0 {
+                return None;
+            }
+            let mut buf = vec![0u16; (len as usize).div_ceil(2)];
+            let status = RegGetValueW(
+                key,
+                std::ptr::null(),
+                name.as_ptr(),
+                RRF_RT_REG_SZ | RRF_RT_REG_EXPAND_SZ,
+                &mut kind,
+                buf.as_mut_ptr() as *mut _,
+                &mut len,
+            );
+            if status != ERROR_SUCCESS {
+                return None;
+            }
+            let text = String::from_utf16_lossy(&buf);
+            Some(text.trim_end_matches('\0').to_owned())
+        };
+        let value = read();
+        RegCloseKey(key);
+        value.filter(|v| !v.trim().is_empty()).map(OsString::from)
+    }
+}
+
+/// The user's own `PATH` entries; `None` outside Windows (see the Windows impl).
+#[cfg(not(windows))]
+pub fn user_path() -> Option<OsString> {
+    None
+}
+
+/// `path` followed by the [`user_path`] entries it lacks.
+pub fn with_user_path(path: &OsStr) -> OsString {
+    user_path().map_or_else(|| path.to_owned(), |user| append_path_entries(path, &user))
+}
+
+fn append_path_entries(path: &OsStr, extra: &OsStr) -> OsString {
+    let mut dirs: Vec<std::path::PathBuf> = std::env::split_paths(path).filter(|d| !d.as_os_str().is_empty()).collect();
+    for dir in std::env::split_paths(extra).filter(|d| !d.as_os_str().is_empty()) {
+        if !dirs.contains(&dir) {
+            dirs.push(dir);
+        }
+    }
+    std::env::join_paths(dirs).unwrap_or_else(|_| path.to_owned())
+}
+
 #[cfg(test)]
 mod tests {
    use super::*;

+    #[cfg(windows)]
+    #[test]
+    fn user_path_reads_the_current_users_path() {
+        // This host has a user `Path` only when the test account set one; either way the call
+        // must not fail, and a present value is a non-empty `;`-joined list of directories.
+        if let Some(path) = user_path() {
+            let dirs: Vec<_> = std::env::split_paths(&path).collect();
+            assert!(!dirs.is_empty(), "user PATH should hold at least one directory");
+        }
+    }
+
+    #[test]
+    fn append_path_entries_keeps_the_order_and_adds_what_is_missing() {
+        let join = |dirs: &[&str]| std::env::join_paths(dirs).unwrap();
+        assert_eq!(append_path_entries(&join(&["a", "b"]), &join(&["b", "c"])), join(&["a", "b", "c"]));
+        assert_eq!(append_path_entries(OsStr::new(""), &join(&["c"])), join(&["c"]));
+    }
+
    #[test]
    fn shell_env_adds_only_what_the_process_lacks_and_the_overlay_wins() {
        set_shell_env(vec![("OPENIDEA_SHELL_ONLY_VAR".into(), "1".into()), ("PATH".into(), "/from/shell".into())]);
@@ -363,4 +482,23 @@ mod tests {
        prepare(&mut cmd);
        assert_eq!(cmd.get_envs().find(|(k, _)| *k == "PATH").and_then(|(_, v)| v), Some(OsStr::new("/custom")));
    }
+
+    #[test]
+    fn find_executable_finds_bare_names_on_the_given_path() {
+        let dir = tempfile::tempdir().unwrap();
+        let a = dir.path().join("a");
+        let b = dir.path().join("b");
+        std::fs::create_dir_all(&a).unwrap();
+        std::fs::create_dir_all(&b).unwrap();
+        std::fs::write(a.join("agent"), "#!/bin/sh\n").unwrap();
+        std::fs::write(b.join("agent.cmd"), "@echo off\n").unwrap();
+        let search = std::env::join_paths([&a, &b]).unwrap();
+        if cfg!(windows) {
+            // The `.cmd` shim wins over a POSIX script `Command` can't start.
+            assert_eq!(find_executable("agent", &search), Some(b.join("agent.cmd")));
+        } else {
+            assert_eq!(find_executable("agent", &search), Some(a.join("agent")));
+        }
+        assert_eq!(find_executable("nope", &search), None);
+    }
 }
@@ -103,10 +103,19 @@ impl Default for DeploymentSettings {
    }
 }

-/// An SFTP server and how project folders map onto it.
+#[derive(Clone, Copy, Debug, Default, PartialEq, Eq, Serialize, Deserialize, Type)]
+#[serde(rename_all = "camelCase")]
+pub enum DeploymentType {
+    #[default]
+    Sftp,
+    Local,
+}
+
+/// A deployment filesystem and how project folders map onto it.
 #[derive(Clone, Debug, Default, PartialEq, Eq, Serialize, Deserialize, Type)]
 #[serde(default, rename_all = "camelCase")]
 pub struct DeploymentServer {
+    pub kind: DeploymentType,
    pub id: String,
    pub name: String,
    /// [`SshConfiguration::id`].
@@ -148,3 +157,23 @@ pub struct RunTarget {
    pub node: String,
    pub java: String,
 }
+
+#[cfg(test)]
+mod deployment_tests {
+    use super::*;
+
+    #[test]
+    fn deployment_type_defaults_and_round_trips() {
+        let legacy: DeploymentServer =
+            serde_json::from_str(r#"{"id":"existing","sshConfig":"ssh","rootPath":"/srv"}"#).unwrap();
+        assert_eq!(legacy.kind, DeploymentType::Sftp);
+        assert_eq!(legacy.ssh_config, "ssh");
+        for kind in [DeploymentType::Sftp, DeploymentType::Local] {
+            let server = DeploymentServer { kind, ..legacy.clone() };
+            assert_eq!(
+                serde_json::from_str::<DeploymentServer>(&serde_json::to_string(&server).unwrap()).unwrap(),
+                server
+            );
+        }
+    }
+}
@@ -178,7 +178,7 @@ pub struct CustomKeymap {
 pub struct GeneralSettings {
    pub reopen_last_project: bool,
    pub confirm_exit: bool,
-    /// Where Open… puts a project while one is open: `ask` | `new` | `same`.
+    /// Where Open… puts a project while one is open: `ask` | `new` | `same` | `attach`.
    pub open_project_in: String,
    /// Initial folder of the Open / Clone dialogs; empty = the OS default.
    pub default_project_directory: String,
@@ -276,6 +276,8 @@ pub struct AppearanceSettings {
    /// Apply `ui_font_family` / `ui_font_size` (otherwise the theme's).
    pub use_custom_font: bool,
    pub ui_font_family: String,
+    /// Font tried when `ui_font_family` lacks a glyph; empty = none.
+    pub ui_font_fallback: String,
    pub contrast_scrollbars: bool,
    /// Adjust colours for red-green vision deficiency.
    pub red_green_vision: bool,
@@ -285,11 +287,14 @@ pub struct AppearanceSettings {
    pub project_colors_in_toolbar: bool,
    pub dnd_with_alt_only: bool,
    pub menu_icons: bool,
+    /// `hamburger` | `merged`: main menu presentation in the frameless title bar.
+    pub main_menu_style: String,
    /// `subpixel` | `greyscale` | `none`
    pub ide_antialiasing: String,
    pub editor_antialiasing: String,
    pub show_tool_window_bars: bool,
    pub show_tool_window_names: bool,
+    pub show_tool_window_badges: bool,
    pub widescreen_tool_windows: bool,
    /// Status bar widgets shown (`true`) or hidden (`false`) by the user
    /// (status bar context menu); widgets not listed use their default.
@@ -323,6 +328,7 @@ impl Default for AppearanceSettings {
            zoom: 100,
            use_custom_font: false,
            ui_font_family: "Inter".into(),
+            ui_font_fallback: String::new(),
            contrast_scrollbars: false,
            red_green_vision: false,
            different_tool_window_background: false,
@@ -331,10 +337,12 @@ impl Default for AppearanceSettings {
            project_colors_in_toolbar: true,
            dnd_with_alt_only: false,
            menu_icons: true,
+            main_menu_style: "hamburger".into(),
            ide_antialiasing: "greyscale".into(),
            editor_antialiasing: "greyscale".into(),
            show_tool_window_bars: true,
            show_tool_window_names: false,
+            show_tool_window_badges: true,
            widescreen_tool_windows: false,
            status_bar_widgets: BTreeMap::new(),
            main_toolbar: None,
@@ -342,6 +350,15 @@ impl Default for AppearanceSettings {
    }
 }

+/// Imported editor colour scheme on top of a built-in base.
+#[derive(Clone, Debug, PartialEq, Serialize, Deserialize, Type)]
+#[serde(rename_all = "camelCase")]
+pub struct CustomColorScheme {
+    pub name: String,
+    pub parent: String,
+    pub attributes: BTreeMap<String, TextAttributesOverride>,
+}
+
 #[derive(Clone, Debug, PartialEq, Serialize, Deserialize, Type)]
 #[serde(default, rename_all = "camelCase")]
 pub struct EditorSettings {
@@ -357,6 +374,8 @@ pub struct EditorSettings {
    pub format_on_save: bool,
    /// Editor colour scheme id; `theme-default` follows the IDE theme.
    pub color_scheme: String,
+    /// Imported editor schemes, stored in user settings.
+    pub custom_schemes: BTreeMap<String, CustomColorScheme>,
    /// Color Scheme edits: scheme id → attribute id → override.
    pub color_overrides: BTreeMap<String, BTreeMap<String, TextAttributesOverride>>,
    /// Color Scheme › Language Defaults › Semantic highlighting: local variables and
@@ -404,6 +423,7 @@ impl Default for EditorSettings {
            format_on_save: false,
            color_scheme: "theme-default".into(),
            color_overrides: BTreeMap::new(),
+            custom_schemes: BTreeMap::new(),
            semantic_highlighting: false,
            rainbow_brackets: false,
            ligatures: false,
@@ -434,6 +454,8 @@ impl Default for EditorSettings {
 pub struct FileSettings {
    /// Save on focus loss / tab switch, like IDEA.
    pub auto_save: bool,
+    /// Re-check open files against disk when the IDE window gains focus.
+    pub sync_on_focus: bool,
    pub exclude: Vec<String>,
    /// Ignored Files and Folders: name patterns hidden everywhere; see [`crate::ignored`].
    pub ignored_names: Vec<String>,
@@ -465,6 +487,7 @@ impl Default for FileSettings {
    fn default() -> Self {
        Self {
            auto_save: true,
+            sync_on_focus: true,
            exclude: vec!["**/.git".into(), "**/node_modules".into(), "**/target".into()],
            ignored_names: crate::ignored::DEFAULT_IGNORED_NAMES.iter().map(|s| (*s).into()).collect(),
            trim_trailing_whitespace: true,
@@ -485,9 +508,50 @@ pub struct LanguagesSettings {
    pub rust: RustSettings,
    pub go: GoSettings,
    pub typescript: TypeScriptSettings,
+    pub prettier: PrettierSettings,
    pub java: JavaSettings,
 }

+#[derive(Clone, Debug, PartialEq, Serialize, Deserialize, Type)]
+#[serde(default, rename_all = "camelCase")]
+pub struct PrettierSettings {
+    /// Empty path: project node_modules, managed installation, then PATH.
+    pub path: String,
+    pub languages: Vec<String>,
+    /// Prefer Prettier even when a language server offers formatting.
+    pub prefer: bool,
+    pub run_on_save: bool,
+}
+
+impl Default for PrettierSettings {
+    fn default() -> Self {
+        Self {
+            path: String::new(),
+            languages: [
+                "markdown",
+                "yaml",
+                "css",
+                "scss",
+                "less",
+                "html",
+                "graphql",
+                "javascript",
+                "javascriptreact",
+                "typescript",
+                "typescriptreact",
+                "json",
+                "jsonc",
+                "vue",
+            ]
+            .into_iter()
+            .map(String::from)
+            .collect(),
+            prefer: false,
+            run_on_save: false,
+        }
+    }
+}
+
 #[derive(Clone, Debug, PartialEq, Serialize, Deserialize, Type)]
 #[serde(default, rename_all = "camelCase")]
 pub struct PythonSettings {
@@ -546,6 +610,35 @@ pub struct GoSettings {
    pub goroot: String,
    /// Empty = `go env GOPATH`.
    pub gopath: String,
+    pub build_tags: GoBuildTags,
+    pub modules: GoModules,
+}
+
+#[derive(Clone, Debug, PartialEq, Serialize, Deserialize, Type)]
+#[serde(default, rename_all = "camelCase")]
+pub struct GoModules {
+    pub env: BTreeMap<String, String>,
+    pub auto_vendor: bool,
+}
+
+impl Default for GoModules {
+    fn default() -> Self {
+        Self { env: BTreeMap::new(), auto_vendor: true }
+    }
+}
+
+#[derive(Clone, Debug, Default, PartialEq, Serialize, Deserialize, Type)]
+#[serde(default, rename_all = "camelCase")]
+pub struct GoBuildTags {
+    /// Empty values inherit the selected toolchain's defaults.
+    pub os: String,
+    pub arch: String,
+    pub version: String,
+    pub compiler: String,
+    /// Empty = automatic, "1" = enabled, "0" = disabled.
+    pub cgo: String,
+    pub custom: String,
+    pub experiments: String,
 }

 #[derive(Clone, Debug, Default, PartialEq, Serialize, Deserialize, Type)]
@@ -563,12 +656,37 @@ pub struct JavaSettings {
    pub jdtls_vm_args: String,
    /// Build Tools › Maven.
    pub maven: MavenSettings,
+    /// Build Tools › Gradle.
+    pub gradle: GradleSettings,
+}
+
+/// Build Tools › Gradle.
+#[derive(Clone, Debug, Default, PartialEq, Serialize, Deserialize, Type)]
+#[serde(default, rename_all = "camelCase")]
+pub struct GradleSettings {
+    /// Empty = Project JDK; otherwise a JDK home.
+    pub jvm: String,
+    pub distribution: GradleDistribution,
+    /// Used only for the local distribution.
+    pub home: String,
+    /// Empty = Gradle's default user home.
+    pub user_home: String,
+}
+
+#[derive(Clone, Debug, Default, PartialEq, Serialize, Deserialize, Type)]
+#[serde(rename_all = "camelCase")]
+pub enum GradleDistribution {
+    #[default]
+    Wrapper,
+    Local,
 }

 /// Build Tools › Maven.
 #[derive(Clone, Debug, Default, PartialEq, Serialize, Deserialize, Type)]
 #[serde(default, rename_all = "camelCase")]
 pub struct MavenSettings {
+    /// Project-relative root POMs removed from the Maven project model.
+    pub unlinked_projects: Vec<String>,
    /// Maven home (or its `mvn` executable); empty = the project's `mvnw`, else `mvn` on `PATH`.
    pub home: String,
    /// User `settings.xml` (`-s`); empty = `~/.m2/settings.xml`.
@@ -647,6 +765,44 @@ impl Settings {
 mod tests {
    use super::*;

+    #[test]
+    fn ui_font_fallback_defaults_empty_and_round_trips() {
+        let old: Settings = serde_json::from_str(r#"{"appearance":{"useCustomFont":true}}"#).unwrap();
+        assert!(old.appearance.ui_font_fallback.is_empty());
+        for family in ["", "Songti SC", "Maple Mono NF CN"] {
+            let mut settings = Settings::default();
+            settings.appearance.ui_font_fallback = family.into();
+            let json = serde_json::to_value(&settings).unwrap();
+            assert_eq!(json["appearance"]["uiFontFallback"], family);
+            let restored: Settings = serde_json::from_value(json).unwrap();
+            assert_eq!(restored.appearance.ui_font_fallback, family);
+        }
+    }
+
+    #[test]
+    fn tool_window_badges_default_on_and_round_trip() {
+        let old: Settings = serde_json::from_str(r#"{"appearance":{"showToolWindowNames":true}}"#).unwrap();
+        assert!(old.appearance.show_tool_window_badges);
+        assert!(Settings::default().appearance.show_tool_window_badges);
+        for enabled in [false, true] {
+            let mut settings = Settings::default();
+            settings.appearance.show_tool_window_badges = enabled;
+            let json = serde_json::to_value(&settings).unwrap();
+            assert_eq!(json["appearance"]["showToolWindowBadges"], enabled);
+            let restored: Settings = serde_json::from_value(json).unwrap();
+            assert_eq!(restored.appearance.show_tool_window_badges, enabled);
+        }
+    }
+
+    #[test]
+    fn main_menu_style_defaults_and_round_trips() {
+        let old: Settings = serde_json::from_str(r#"{"appearance":{"compactMode":true}}"#).unwrap();
+        assert_eq!(old.appearance.main_menu_style, "hamburger");
+        let merged: Settings = serde_json::from_str(r#"{"appearance":{"mainMenuStyle":"merged"}}"#).unwrap();
+        assert_eq!(merged.appearance.main_menu_style, "merged");
+        assert_eq!(serde_json::to_value(merged).unwrap()["appearance"]["mainMenuStyle"], "merged");
+    }
+
    #[test]
    fn editor_font_weights_default_to_regular_and_bold() {
        let json = serde_json::to_value(Settings::default()).unwrap();
@@ -691,3 +847,57 @@ mod tests {
        assert!(Settings::default().files.file_types.is_empty());
    }
 }
+
+#[cfg(test)]
+mod maven_linkage_tests {
+    use super::*;
+
+    #[test]
+    fn maven_linkage_defaults_and_round_trips() {
+        let old: MavenSettings = serde_json::from_str(r#"{"home":"/opt/maven"}"#).unwrap();
+        assert!(old.unlinked_projects.is_empty());
+        let settings =
+            MavenSettings { unlinked_projects: vec!["pom.xml".into(), "services/api/pom.xml".into()], ..old };
+        let encoded = serde_json::to_string(&settings).unwrap();
+        assert!(encoded.contains("unlinkedProjects"));
+        assert_eq!(serde_json::from_str::<MavenSettings>(&encoded).unwrap(), settings);
+    }
+}
+
+#[cfg(test)]
+mod gradle_settings_tests {
+    use super::*;
+
+    #[test]
+    fn defaults_and_round_trip() {
+        let old: JavaSettings = serde_json::from_str(r#"{"jdk":"/jdk"}"#).unwrap();
+        assert_eq!(old.gradle, GradleSettings::default());
+        for distribution in [GradleDistribution::Wrapper, GradleDistribution::Local] {
+            let mut settings = Settings::default();
+            settings.languages.java.gradle = GradleSettings {
+                jvm: "/jdk21".into(),
+                distribution,
+                home: "/gradle".into(),
+                user_home: "/cache/gradle".into(),
+            };
+            let restored: Settings = serde_json::from_str(&serde_json::to_string(&settings).unwrap()).unwrap();
+            assert_eq!(restored.languages.java.gradle, settings.languages.java.gradle);
+        }
+    }
+}
+
+#[cfg(test)]
+mod go_module_tests {
+    use super::*;
+    #[test]
+    fn old_go_settings_inherit_module_defaults() {
+        let old: GoSettings = serde_json::from_str(r#"{"goroot":"/go"}"#).unwrap();
+        assert!(old.modules.auto_vendor);
+        assert!(old.modules.env.is_empty());
+        let configured: GoSettings =
+            serde_json::from_str(r#"{"modules":{"autoVendor":false,"env":{"GOPRIVATE":"example.com/private"}}}"#)
+                .unwrap();
+        assert!(!configured.modules.auto_vendor);
+        assert_eq!(configured.modules.env["GOPRIVATE"], "example.com/private");
+    }
+}
@@ -99,6 +99,44 @@ pub struct WorkspaceEdit {
    pub files: Vec<FileEdit>,
 }

+impl WorkspaceEdit {
+    /// Coalesces aliases of the same file before applying edits against its original text.
+    /// Resource operations separate batches because later edits may use the new contents.
+    pub fn deduplicate(&mut self) {
+        let mut files = Vec::new();
+        let mut batch = std::collections::HashMap::<std::path::PathBuf, usize>::new();
+        let mut resolve_aliases = true;
+        for file in std::mem::take(&mut self.files) {
+            match file {
+                FileEdit::Edit { path, edits } => {
+                    let path = if resolve_aliases {
+                        dunce::canonicalize(&path).unwrap_or_else(|_| path.to_path_buf())
+                    } else {
+                        path.to_path_buf()
+                    };
+                    let index = *batch.entry(path.clone()).or_insert_with(|| {
+                        files.push(FileEdit::Edit { path: path.into(), edits: Vec::new() });
+                        files.len() - 1
+                    });
+                    let FileEdit::Edit { edits: own, .. } = &mut files[index] else { unreachable!() };
+                    for edit in edits {
+                        if !own.contains(&edit) {
+                            own.push(edit);
+                        }
+                    }
+                }
+                op => {
+                    batch.clear();
+                    // Later paths refer to a filesystem state the resource operation has yet to create.
+                    resolve_aliases = false;
+                    files.push(op);
+                }
+            }
+        }
+        self.files = files;
+    }
+}
+
 #[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize, Type)]
 #[serde(tag = "kind", rename_all = "camelCase")]
 pub enum FileEdit {
@@ -203,3 +241,34 @@ pub struct OutlineItem {

 /// Fuzzy-match highlight: indices (in chars of the displayed string) that matched.
 pub type MatchIndices = Vec<u32>;
+
+#[cfg(all(test, unix))]
+mod workspace_edit_tests {
+    use super::*;
+
+    #[test]
+    fn aliases_are_one_edit_but_resource_operations_preserve_order() {
+        let dir = tempfile::tempdir().unwrap();
+        let real = dir.path().join("main.cpp");
+        let alias = dir.path().join("alias.cpp");
+        std::fs::write(&real, "add()").unwrap();
+        std::os::unix::fs::symlink(&real, &alias).unwrap();
+        let change = TextEdit { range: Range::new(Pos::new(0, 0), Pos::new(0, 3)), new_text: "sum_values".into() };
+        let edit = |path: PathBuf| FileEdit::Edit { path: path.into(), edits: vec![change.clone()] };
+        let mut workspace = WorkspaceEdit {
+            files: vec![
+                edit(real.clone()),
+                edit(alias),
+                FileEdit::Create { path: dir.path().join("other").into(), overwrite: false },
+                edit(real),
+            ],
+        };
+        workspace.deduplicate();
+        assert_eq!(workspace.files.len(), 3);
+        let FileEdit::Edit { edits, .. } = &workspace.files[0] else { panic!() };
+        assert_eq!(edits, &[change]);
+        let once = workspace.clone();
+        workspace.deduplicate();
+        assert_eq!(workspace, once);
+    }
+}
@@ -0,0 +1,233 @@
+//! Where the IDE looks up the executables it runs: language servers, the tools
+//! their settings come from, installers. An app started from the desktop gets a
+//! minimal `PATH`, and version managers set theirs up in shell rc files.
+
+use crate::process::{host_var_os, login_env};
+use crate::version_managers;
+use std::collections::HashSet;
+use std::ffi::{OsStr, OsString};
+use std::path::{Path, PathBuf};
+
+/// Where executables are looked up: this process's `PATH` (the login shell's in the
+/// app), the login shell's `PATH` as last read, then per-user directories and mise's,
+/// asdf's and pyenv's shims, for when the shell's setup didn't reach the app. Language server
+/// launchers, their settings hooks and tool detection all look here, so a settings
+/// hook finds the executable its server is launched from.
+pub fn search_path() -> OsString {
+    let home = std::env::var_os("HOME").or_else(|| std::env::var_os("USERPROFILE")).map(PathBuf::from);
+    let shell_path = login_env().and_then(|env| env.iter().find(|(k, _)| k == "PATH").map(|(_, v)| v.clone()));
+    let shims: Vec<PathBuf> = version_managers::managers().iter().map(|m| m.shims()).collect();
+    // The Windows user `PATH` may not reach a process started before it was set; append its
+    // entries after the inherited ones so missing user tools still resolve.
+    let user_path = crate::process::user_path();
+    let dirs = search_dirs(
+        host_var_os("PATH").as_deref(),
+        shell_path.as_deref(),
+        user_path.as_deref(),
+        home.as_deref(),
+        &shims,
+    );
+    std::env::join_paths(dirs).unwrap_or_default()
+}
+
+/// Resolves a command on the shared path, or an explicit path relative to `root`.
+pub fn find_command(command: &str, search: &OsStr, root: &Path) -> Option<PathBuf> {
+    let path = Path::new(command);
+    let explicit = path.parent().is_some_and(|p| !p.as_os_str().is_empty());
+    let pathext = host_var_os("PATHEXT");
+    let names = crate::process::executable_names(command, cfg!(windows), pathext.as_deref().and_then(OsStr::to_str));
+    let dirs = if explicit {
+        vec![root.to_path_buf()]
+    } else {
+        std::env::split_paths(search).filter(|p| !p.as_os_str().is_empty()).map(|p| root.join(p)).collect()
+    };
+    dirs.into_iter().find_map(|dir| names.iter().map(|name| dir.join(name)).find(|p| is_executable(p)))
+}
+
+fn is_executable(path: &Path) -> bool {
+    let Ok(metadata) = path.metadata() else { return false };
+    if !metadata.is_file() {
+        return false;
+    }
+    #[cfg(unix)]
+    {
+        use std::os::unix::fs::PermissionsExt;
+        metadata.permissions().mode() & 0o111 != 0
+    }
+    #[cfg(not(unix))]
+    true
+}
+
+/// [`search_path`]'s directories, in order and once each. Only absolute ones: a
+/// relative entry (`.`, `node_modules/.bin`) resolves against the project, which
+/// could then supply the tools the IDE runs. One that can't be joined (a `:` in a
+/// directory name) is left out rather than failing the whole path.
+fn search_dirs(
+    process_path: Option<&OsStr>,
+    shell_path: Option<&OsStr>,
+    user_path: Option<&OsStr>,
+    home: Option<&Path>,
+    shims: &[PathBuf],
+) -> Vec<PathBuf> {
+    let mut dirs: Vec<PathBuf> =
+        process_path.into_iter().chain(shell_path).chain(user_path).flat_map(std::env::split_paths).collect();
+    if let Some(home) = home {
+        dirs.extend(USER_DIRS.iter().map(|d| home.join(d)));
+        dirs.extend(nvm_bins(&home.join(".nvm/versions/node")));
+    }
+    // Version managers' shims after real tool directories: a shim exists for a command any
+    // installed version has, and fails when the selected one lacks it. Before the system's,
+    // as the managers' shell setup puts them.
+    dirs.extend(home.map(|h| h.join(".pyenv/shims")));
+    dirs.extend(shims.iter().cloned());
+    dirs.extend(SYSTEM_DIRS.iter().map(PathBuf::from));
+    let mut seen = HashSet::new();
+    dirs.retain(|d| d.is_absolute() && std::env::join_paths([d]).is_ok() && seen.insert(d.clone()));
+    dirs
+}
+
+/// Tool directories below the home directory.
+const USER_DIRS: &[&str] = &[
+    ".cargo/bin",
+    ".local/bin",
+    "go/bin",
+    // `dotnet tool install --global` puts fsautocomplete, csharp-ls and friends here.
+    ".dotnet/tools",
+    ".bun/bin",
+    ".deno/bin",
+    ".npm-global/bin",
+    ".volta/bin",
+    // Set up in shell rc files: fnm's default Node and pnpm's global bin (Linux, then macOS).
+    ".local/share/fnm/aliases/default/bin",
+    "Library/Application Support/fnm/aliases/default/bin",
+    ".fnm/aliases/default/bin",
+    ".local/share/pnpm/bin",
+    ".local/share/pnpm",
+    "Library/pnpm/bin",
+    "Library/pnpm",
+];
+
+const SYSTEM_DIRS: &[&str] = &["/opt/homebrew/bin", "/usr/local/go/bin", "/usr/local/bin", "/usr/bin", "/bin"];
+
+/// Whether `dir` is one of the system's own bin directories, which [`search_path`] adds
+/// whatever `PATH` holds.
+pub fn is_system_dir(dir: &Path) -> bool {
+    SYSTEM_DIRS.iter().any(|d| Path::new(d) == dir)
+}
+
+/// The `bin` directories of nvm's Node versions in `dir`, newest first.
+fn nvm_bins(dir: &Path) -> Vec<PathBuf> {
+    let mut versions: Vec<(Vec<u64>, PathBuf)> = std::fs::read_dir(dir)
+        .into_iter()
+        .flatten()
+        .flatten()
+        .map(|e| (version_key(&e.file_name().to_string_lossy()), e.path().join("bin")))
+        .collect();
+    versions.sort();
+    versions.into_iter().rev().map(|(_, bin)| bin).collect()
+}
+
+/// `v22.10.1` as `[22, 10, 1]`: v22 is newer than v9, v20.10 newer than v20.9.
+fn version_key(name: &str) -> Vec<u64> {
+    name.trim_start_matches('v').split('.').map(|n| n.parse().unwrap_or(0)).collect()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn commands_resolve_on_path_and_explicit_paths_under_root() {
+        let dir = tempfile::tempdir().unwrap();
+        let bin = dir.path().join("bin");
+        std::fs::create_dir(&bin).unwrap();
+        let name = if cfg!(windows) { "ngserver.cmd" } else { "ngserver" };
+        std::fs::write(bin.join(name), "").unwrap();
+        #[cfg(unix)]
+        {
+            use std::os::unix::fs::PermissionsExt;
+            std::fs::set_permissions(bin.join(name), std::fs::Permissions::from_mode(0o755)).unwrap();
+        }
+        let search = std::env::join_paths([&bin]).unwrap();
+        assert_eq!(find_command("ngserver", &search, dir.path()), Some(bin.join(name)));
+        assert_eq!(find_command("bin/ngserver", &search, dir.path()), Some(bin.join(name)));
+        assert_eq!(find_command(bin.join(name).to_str().unwrap(), &search, dir.path()), Some(bin.join(name)));
+        assert_eq!(find_command("absent", &search, dir.path()), None);
+        for command in ["bin/ngserver", bin.join(name).to_str().unwrap()] {
+            assert_eq!(find_command(command, OsStr::new(""), dir.path()), Some(bin.join(name)));
+        }
+    }
+
+    #[cfg(unix)]
+    #[test]
+    fn non_executable_files_do_not_shadow_commands() {
+        use std::os::unix::fs::PermissionsExt;
+        let tmp = tempfile::tempdir().unwrap();
+        let dirs = [tmp.path().join("first"), tmp.path().join("second")];
+        for (dir, mode) in dirs.iter().zip([0o644, 0o755]) {
+            std::fs::create_dir(dir).unwrap();
+            let file = dir.join("ngserver");
+            std::fs::write(&file, "#!/bin/sh\n").unwrap();
+            std::fs::set_permissions(file, std::fs::Permissions::from_mode(mode)).unwrap();
+        }
+        let path = std::env::join_paths(&dirs).unwrap();
+        assert_eq!(find_command("ngserver", &path, tmp.path()), Some(dirs[1].join("ngserver")));
+        assert_eq!(find_command("first/ngserver", &path, tmp.path()), None);
+    }
+
+    #[cfg(unix)]
+    #[test]
+    fn search_dirs_put_the_process_path_first_and_shims_after_real_tools() {
+        let shims = [PathBuf::from("/home/me/.local/share/mise/shims"), "/home/me/.asdf/shims".into()];
+        let dirs = search_dirs(
+            Some(OsStr::new("/usr/bin:.:node_modules/.bin:/opt/tools")),
+            // nushell prints `$PATH` as is.
+            Some(OsStr::new("$PATH:/opt/tools:/home/me/.asdf/shims")),
+            None,
+            Some(Path::new("/home/me")),
+            &shims,
+        );
+        let at = |d: &str| dirs.iter().position(|p| p == Path::new(d)).unwrap();
+        assert_eq!(dirs[..3], [PathBuf::from("/usr/bin"), "/opt/tools".into(), "/home/me/.asdf/shims".into()]);
+        assert!(at("/home/me/.npm-global/bin") < at("/home/me/.pyenv/shims"));
+        // Global .NET tools (fsautocomplete, csharp-ls) install here, off PATH.
+        assert!(at("/home/me/.dotnet/tools") < at("/usr/local/bin"));
+        assert!(at("/home/me/.local/share/mise/shims") < at("/usr/local/bin"));
+        assert!(dirs.iter().all(|d| d.is_absolute()));
+        let unique: HashSet<&PathBuf> = dirs.iter().collect();
+        assert_eq!(unique.len(), dirs.len());
+        // A `:` can't be in a `PATH` entry: those below such a home are left out.
+        let dirs = search_dirs(Some(OsStr::new("/usr/bin")), None, None, Some(Path::new("/home/a:b")), &[]);
+        assert!(dirs.contains(&PathBuf::from("/usr/bin")) && !dirs.iter().any(|d| d.starts_with("/home")));
+    }
+
+    #[test]
+    fn search_dirs_append_user_path_entries_once_after_the_inherited_path() {
+        let (system, dup, usertool) =
+            if cfg!(windows) { ("C:/system", "C:/dup", "C:/usertool") } else { ("/system", "/dup", "/usertool") };
+        let home = Path::new(if cfg!(windows) { "C:/home/me" } else { "/home/me" });
+        let join = |dirs: &[&str]| std::env::join_paths(dirs.iter().map(PathBuf::from)).unwrap();
+        let inherited = join(&[system, dup]);
+        let user = join(&[dup, usertool]);
+        let dirs = search_dirs(Some(inherited.as_os_str()), None, Some(user.as_os_str()), Some(home), &[]);
+        let at = |d: &str| dirs.iter().position(|p| p == Path::new(d)).unwrap();
+        // User entries follow the inherited PATH, de-duplicated, ahead of the fallbacks.
+        assert_eq!(dirs.iter().filter(|d| *d == Path::new(dup)).count(), 1);
+        assert!(at(dup) < at(usertool));
+        // And before this platform's home/system fallbacks.
+        let fallback = dirs.iter().position(|d| d == &home.join(USER_DIRS[0])).unwrap();
+        assert!(at(usertool) < fallback);
+    }
+
+    #[test]
+    fn nvm_versions_newest_first() {
+        let dir = std::env::temp_dir().join(format!("openidea-nvm-{}", std::process::id()));
+        for v in ["v9.11.2", "v20.9.0", "v22.1.0", "v20.10.0"] {
+            std::fs::create_dir_all(dir.join(v).join("bin")).unwrap();
+        }
+        let bins = nvm_bins(&dir);
+        std::fs::remove_dir_all(&dir).unwrap();
+        let names: Vec<_> = bins.iter().map(|b| b.parent().unwrap().file_name().unwrap().to_owned()).collect();
+        assert_eq!(names, ["v22.1.0", "v20.10.0", "v20.9.0", "v9.11.2"]);
+    }
+}
@@ -213,8 +213,12 @@ pub fn collect(spec: &CoverageReportSpec) -> IdeResult<CoverageSuite> {
                .output()
                .map_err(|e| IdeError::unavailable(format!("cannot run {program}: {e}")))?;
            if !out.status.success() {
-                let text = String::from_utf8_lossy(&out.stderr).trim().to_owned();
-                let text = if text.is_empty() { String::from_utf8_lossy(&out.stdout).trim().to_owned() } else { text };
+                let text = ide_core::output_encoding::decode_tool_output(&out.stderr).trim().to_owned();
+                let text = if text.is_empty() {
+                    ide_core::output_encoding::decode_tool_output(&out.stdout).trim().to_owned()
+                } else {
+                    text
+                };
                return Err(IdeError::not_found(format!("exporting the coverage data failed: {text}")));
            }
            let text = read_report(lcov)?;
@@ -6,6 +6,7 @@ edition.workspace = true
 license.workspace = true

 [dependencies]
+tempfile.workspace = true
 ide-core.workspace = true
 ide-language.workspace = true
 ide-jsonrpc.workspace = true
@@ -63,6 +63,12 @@ fn builtin(adapter: &str) -> Option<DebuggerConfig> {
            "tcp",
            "Install the CodeLLDB adapter (https://github.com/vadimcn/codelldb/releases) and put `codelldb` on PATH",
        ),
+        "kotlin-debug-adapter" => cfg(
+            "kotlin-debug-adapter",
+            &[],
+            "stdio",
+            "Install the Kotlin Debug Adapter from Settings > Language Servers",
+        ),
        "debugpy" => cfg("python3", &["-m", "debugpy.adapter"], "stdio", "pip install debugpy"),
        "js-debug" => cfg(
            "js-debug-adapter",
@@ -342,8 +348,17 @@ pub struct AdapterIo {
    pub port: Option<u16>,
    /// Recent stderr lines of the adapter process, for error messages.
    pub stderr: Arc<parking_lot::Mutex<Vec<String>>>,
+    /// (category, line) printed by the debuggee when it shares the adapter's stdio.
+    pub program_output: Option<ProgramOutput>,
 }

+pub type ProgramOutput = tokio::sync::mpsc::UnboundedReceiver<(&'static str, String)>;
+type ProgramSink = tokio::sync::mpsc::UnboundedSender<(&'static str, String)>;
+
+/// Delve's debuggee inherits its stdio; no DAP output event carries what the program prints.
+const SHARES_STDIO: &str = "delve";
+const DELVE_BANNER: &str = "DAP server listening at:";
+
 pub type LaunchFuture = Pin<Box<dyn Future<Output = IdeResult<AdapterIo>> + Send>>;

 /// Starts adapters. Tests substitute in-memory adapters.
@@ -379,6 +394,7 @@ impl AdapterLauncher for ProcessLauncher {
                    child: None,
                    port: Some(port),
                    stderr,
+                    program_output: None,
                });
            }
            let embedded = match spec.connect.as_deref().filter(|_| spec.transport == Transport::Tcp) {
@@ -401,6 +417,7 @@ impl AdapterLauncher for ProcessLauncher {
                    child: None,
                    port: Some(*port),
                    stderr,
+                    program_output: None,
                });
            }
            if spec.adapter == DEBUGPY_TOOL {
@@ -439,8 +456,14 @@ impl AdapterLauncher for ProcessLauncher {
                .kill_on_drop(true);
            let mut child =
                cmd.spawn().map_err(|e| IdeError::unavailable(format!("failed to start {}: {e}", binary.display())))?;
+            let (program_sink, program_output) = if spec.adapter == SHARES_STDIO {
+                let (tx, rx) = tokio::sync::mpsc::unbounded_channel();
+                (Some(tx), Some(rx))
+            } else {
+                (None, None)
+            };
            if let Some(err) = child.stderr.take() {
-                pump_lines(err, spec.adapter.clone(), stderr.clone());
+                pump_lines(err, spec.adapter.clone(), stderr.clone(), program_sink.clone().map(|tx| (tx, "stderr")));
            }
            match port {
                None => {
@@ -452,11 +475,12 @@ impl AdapterLauncher for ProcessLauncher {
                        child: Some(child),
                        port: None,
                        stderr,
+                        program_output,
                    })
                }
                Some(port) => {
                    if let Some(out) = child.stdout.take() {
-                        pump_lines(out, spec.adapter.clone(), stderr.clone());
+                        pump_lines(out, spec.adapter.clone(), stderr.clone(), program_sink.map(|tx| (tx, "stdout")));
                    }
                    let timeout = if embedded.is_some() { EMBEDDED_START_TIMEOUT } else { CONNECT_TIMEOUT };
                    let stream = match connect_with_retries(LOOPBACK, port, Some(&mut child), timeout).await {
@@ -478,6 +502,7 @@ impl AdapterLauncher for ProcessLauncher {
                        child: Some(child),
                        port: Some(port),
                        stderr,
+                        program_output,
                    })
                }
            }
@@ -489,9 +514,15 @@ fn pump_lines<R: AsyncRead + Unpin + Send + 'static>(
    stream: R,
    name: String,
    sink: Arc<parking_lot::Mutex<Vec<String>>>,
+    program: Option<(ProgramSink, &'static str)>,
 ) {
    tokio::spawn(ide_jsonrpc::output::read_lines(stream, move |line| {
        tracing::debug!(target: "ide_dap::adapter", "[{name}] {line}");
+        if let Some((tx, category)) = &program
+            && !line.starts_with(DELVE_BANNER)
+        {
+            let _ = tx.send((category, format!("{line}\n")));
+        }
        push_line(&sink, line);
    }));
 }
@@ -543,6 +574,18 @@ async fn connect_with_retries(
 mod tests {
    use super::*;

+    #[tokio::test]
+    async fn program_output_is_forwarded_without_the_adapter_banner() {
+        let (tx, mut rx) = tokio::sync::mpsc::unbounded_channel();
+        let sink = Arc::default();
+        let text: &[u8] = b"DAP server listening at: 127.0.0.1:1\n[hello two words]\nno newline";
+        pump_lines(text, "delve".into(), Arc::clone(&sink), Some((tx, "stdout")));
+        assert_eq!(rx.recv().await, Some(("stdout", "[hello two words]\n".into())));
+        assert_eq!(rx.recv().await, Some(("stdout", "no newline\n".into())));
+        assert_eq!(rx.recv().await, None);
+        assert_eq!(sink.lock().len(), 3);
+    }
+
    /// Managed tools win over `PATH`, and debugpy falls back to the private copy.
    #[cfg(unix)]
    #[tokio::test]
@@ -70,8 +70,10 @@ pub async fn build(
    let on_output = std::sync::Arc::new(on_output);
    let err_out = on_output.clone();
    let err_task = tokio::spawn(async move {
-        let mut lines = BufReader::new(stderr).lines();
-        while let Ok(Some(line)) = lines.next_line().await {
+        let mut lines = BufReader::new(stderr).split(b'\n');
+        while let Ok(Some(line)) = lines.next_segment().await {
+            let line = ide_core::output_encoding::decode_tool_output(&line);
+            let line = line.trim_end_matches('\r');
            err_out(format!("{line}\n"));
        }
    });
@@ -0,0 +1,218 @@
+//! Package-aligned sources for fwcd's path-based class resolver. Never write into a project.
+use ide_core::{IdeError, IdeResult};
+use serde_json::Value;
+use std::{
+    collections::HashMap,
+    fs,
+    path::{Path, PathBuf},
+};
+
+pub const ADAPTER: &str = "kotlin-debug-adapter";
+
+pub struct SourceMirror {
+    dir: tempfile::TempDir,
+    paths: HashMap<PathBuf, PathBuf>,
+    copies: Vec<(PathBuf, PathBuf)>,
+    source_dir: PathBuf,
+    roots: HashMap<PathBuf, usize>,
+}
+
+impl SourceMirror {
+    pub fn create(project: &Path) -> IdeResult<Self> {
+        let base = fs::canonicalize(std::env::temp_dir())?;
+        // Check before creating anything, including when TMPDIR points into a project.
+        if base.starts_with(fs::canonicalize(project)?) {
+            return Err(IdeError::invalid("Kotlin source mirror must be outside the project"));
+        }
+        let dir = tempfile::Builder::new().prefix("openidea-kotlin-").tempdir_in(base)?;
+        let source_dir = if project.join("src").is_dir() { project.join("src") } else { project.to_owned() };
+        let mut mirror = Self {
+            dir,
+            paths: HashMap::new(),
+            copies: Vec::new(),
+            source_dir: source_dir.clone(),
+            roots: HashMap::new(),
+        };
+        mirror.scan(&source_dir)?;
+        Ok(mirror)
+    }
+
+    pub fn root(&self) -> &Path {
+        self.dir.path()
+    }
+
+    fn scan(&mut self, dir: &Path) -> IdeResult<()> {
+        for entry in fs::read_dir(dir)? {
+            let entry = entry?;
+            let path = entry.path();
+            let kind = entry.file_type()?;
+            if kind.is_dir() {
+                if !matches!(
+                    entry.file_name().to_str(),
+                    Some(".git" | ".gradle" | "build" | "target" | "node_modules" | ".idea" | ".openidea")
+                ) {
+                    self.scan(&path)?;
+                }
+            } else if matches!(path.extension().and_then(|s| s.to_str()), Some("kt" | "java")) {
+                self.add(&path)?;
+            }
+        }
+        Ok(())
+    }
+
+    fn add(&mut self, real: &Path) -> IdeResult<()> {
+        if self.paths.contains_key(real) {
+            return Ok(());
+        }
+        let Ok(text) = fs::read_to_string(real) else {
+            tracing::debug!("Kotlin debug mirror: skipping unreadable {}", real.display());
+            return Ok(());
+        };
+        let language = if real.extension().is_some_and(|e| e == "java") { "java" } else { "kotlin" };
+        let relative = real.strip_prefix(&self.source_dir).unwrap_or(real);
+        let mut components = relative.components();
+        let source_set = components.next().map(|c| PathBuf::from(c.as_os_str())).unwrap_or_default();
+        let next_root = self.roots.len();
+        let index = *self.roots.entry(source_set).or_insert(next_root);
+        let mut mirror = self.root().join(format!("root{index}")).join("src/main").join(language);
+        for part in package(&text).split('.').filter(|s| !s.is_empty()) {
+            if part == ".." || part.contains(['/', '\\']) {
+                tracing::debug!("Kotlin debug mirror: skipping {} (invalid package)", real.display());
+                return Ok(());
+            }
+            mirror.push(part);
+        }
+        mirror.push(real.file_name().ok_or_else(|| IdeError::invalid("Source has no filename"))?);
+        // Same package and file name in one source set (e.g. main and test of a module):
+        // the first wins; breakpoints in the other stay unverified instead of failing the session.
+        if self.paths.values().any(|p| p == &mirror) {
+            tracing::debug!("Kotlin debug mirror: skipping ambiguous {}", real.display());
+            return Ok(());
+        }
+        fs::create_dir_all(mirror.parent().unwrap())?;
+        if link(real, &mirror).is_err() {
+            fs::copy(real, &mirror)?;
+            self.copies.push((real.to_owned(), mirror.clone()));
+        }
+        self.paths.insert(real.to_owned(), mirror);
+        Ok(())
+    }
+
+    pub fn adapter_path(&self, real: &Path) -> Option<PathBuf> {
+        self.paths.get(real).cloned()
+    }
+    pub fn client_path(&self, mirror: &Path) -> Option<PathBuf> {
+        self.paths.iter().find_map(|(real, p)| (p == mirror).then(|| real.clone()))
+    }
+    pub fn refresh(&mut self) -> IdeResult<()> {
+        for (real, mirror) in &self.copies {
+            if real.is_file() {
+                fs::copy(real, mirror)?;
+            }
+        }
+        self.scan(&self.source_dir.clone())
+    }
+    pub fn translate(&self, value: &mut Value) {
+        match value {
+            Value::Object(obj) => {
+                if let Some(path) = obj.get("path").and_then(Value::as_str).and_then(|p| self.client_path(Path::new(p)))
+                {
+                    obj.insert("path".into(), Value::String(path.to_string_lossy().into_owned()));
+                }
+                for child in obj.values_mut() {
+                    self.translate(child);
+                }
+            }
+            Value::Array(items) => {
+                for child in items {
+                    self.translate(child);
+                }
+            }
+            _ => {}
+        }
+    }
+}
+
+#[cfg(unix)]
+fn link(real: &Path, mirror: &Path) -> std::io::Result<()> {
+    std::os::unix::fs::symlink(real, mirror)
+}
+#[cfg(windows)]
+fn link(real: &Path, mirror: &Path) -> std::io::Result<()> {
+    std::os::windows::fs::symlink_file(real, mirror)
+}
+
+// Remove comments before reading the package directive (including nested Kotlin block comments).
+fn package(text: &str) -> String {
+    let mut clean = String::new();
+    let mut chars = text.chars().peekable();
+    let mut depth = 0;
+    while let Some(c) = chars.next() {
+        if c == '/' && chars.peek() == Some(&'*') {
+            chars.next();
+            depth += 1;
+            clean.push(' ');
+        } else if depth > 0 && c == '*' && chars.peek() == Some(&'/') {
+            chars.next();
+            depth -= 1;
+        } else if depth == 0 && c == '/' && chars.peek() == Some(&'/') {
+            for c in chars.by_ref() {
+                if c == '\n' {
+                    clean.push('\n');
+                    break;
+                }
+            }
+        } else if depth == 0 {
+            clean.push(c);
+        }
+    }
+    clean
+        .lines()
+        .find_map(|line| {
+            let rest = line.trim().strip_prefix("package")?;
+            if !rest.starts_with(char::is_whitespace) {
+                return None;
+            }
+            Some(rest.split(';').next().unwrap_or_default().trim().replace('`', ""))
+        })
+        .unwrap_or_default()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn external_mirror_round_trip_and_cleanup() {
+        let project = tempfile::tempdir().unwrap();
+        let real = project.path().join("Main.kt");
+        fs::write(&real, "/* package wrong */\npackage org.example\nfun main() {}\n").unwrap();
+        let mirror = SourceMirror::create(project.path()).unwrap();
+        let path = mirror.adapter_path(&real).unwrap();
+        assert!(!path.starts_with(project.path()));
+        assert!(path.ends_with("src/main/kotlin/org/example/Main.kt"));
+        assert_eq!(fs::read_to_string(&path).unwrap(), fs::read_to_string(&real).unwrap());
+        let mut payload =
+            serde_json::json!({"stackFrames": [{"source": {"path": path}, "line": 6}], "source": {"path": path}});
+        mirror.translate(&mut payload);
+        assert_eq!(payload["stackFrames"][0]["source"]["path"], real.to_string_lossy().as_ref());
+        assert_eq!(payload["source"]["path"], real.to_string_lossy().as_ref());
+        let root = mirror.root().to_owned();
+        drop(mirror);
+        assert!(!root.exists());
+        assert!(real.exists());
+    }
+    #[test]
+    fn copies_refresh_after_save() {
+        let project = tempfile::tempdir().unwrap();
+        let real = project.path().join("Main.java");
+        fs::write(&real, "package example;\nclass Main {}\n").unwrap();
+        let mut mirror = SourceMirror::create(project.path()).unwrap();
+        let path = mirror.adapter_path(&real).unwrap();
+        fs::remove_file(&path).unwrap();
+        fs::copy(&real, &path).unwrap();
+        mirror.copies.push((real.clone(), path.clone()));
+        fs::write(&real, "package example;\nclass Main { int i; }\n").unwrap();
+        mirror.refresh().unwrap();
+        assert_eq!(fs::read(&path).unwrap(), fs::read(&real).unwrap());
+    }
+}
@@ -0,0 +1,166 @@
+//! Keep a suspended JVM stopped until Kotlin's adapter has installed its listeners.
+//! The official 0.4.4 adapter resumes VMStart while constructing its debuggee, before
+//! installing breakpoint hooks. DAP attach completes only after those hooks exist.
+use ide_core::IdeResult;
+use std::{io, time::Duration};
+use tokio::{
+    io::{AsyncRead, AsyncReadExt, AsyncWrite, AsyncWriteExt},
+    net::{TcpListener, TcpStream},
+    sync::oneshot,
+    task::JoinHandle,
+};
+
+pub(crate) struct StartupRelay {
+    release: Option<oneshot::Sender<()>>,
+    task: JoinHandle<()>,
+}
+
+impl StartupRelay {
+    pub async fn start(host: String, port: u16) -> IdeResult<(Self, u16)> {
+        let listener = TcpListener::bind(("127.0.0.1", 0)).await?;
+        let local = listener.local_addr()?.port();
+        let (release, ready) = oneshot::channel();
+        let task = tokio::spawn(async move {
+            let connect = async {
+                let (adapter, _) = listener.accept().await?;
+                let jvm = TcpStream::connect((host.as_str(), port)).await?;
+                adapter.set_nodelay(true)?;
+                jvm.set_nodelay(true)?;
+                Ok::<_, io::Error>((adapter, jvm))
+            };
+            if let Ok(Ok((adapter, jvm))) = tokio::time::timeout(Duration::from_secs(60), connect).await {
+                let (mut ar, mut aw) = adapter.into_split();
+                let (mut jr, mut jw) = jvm.into_split();
+                let upstream = forward(&mut ar, &mut jw, ready);
+                let downstream = tokio::io::copy(&mut jr, &mut aw);
+                // Close both sockets as soon as either side disconnects.
+                tokio::select! {
+                    r = upstream => if let Err(e) = r { tracing::debug!("Kotlin JDWP relay: {e}"); },
+                    _ = downstream => {},
+                }
+            }
+        });
+        Ok((Self { release: Some(release), task }, local))
+    }
+
+    pub fn release(&mut self) {
+        if let Some(ready) = self.release.take() {
+            let _ = ready.send(());
+        }
+    }
+}
+
+impl Drop for StartupRelay {
+    fn drop(&mut self) {
+        self.task.abort();
+    }
+}
+
+async fn packet(reader: &mut (impl AsyncRead + Unpin)) -> io::Result<Vec<u8>> {
+    let mut header = [0; 11];
+    reader.read_exact(&mut header).await?;
+    let len = u32::from_be_bytes(header[..4].try_into().unwrap()) as usize;
+    if !(11..=16 * 1024 * 1024).contains(&len) {
+        return Err(io::Error::new(io::ErrorKind::InvalidData, "Invalid JDWP packet length"));
+    }
+    let mut packet = vec![0; len];
+    packet[..11].copy_from_slice(&header);
+    reader.read_exact(&mut packet[11..]).await?;
+    Ok(packet)
+}
+
+async fn forward(
+    reader: &mut (impl AsyncRead + Unpin),
+    writer: &mut (impl AsyncWrite + Unpin),
+    mut ready: oneshot::Receiver<()>,
+) -> io::Result<()> {
+    let mut handshake = [0; 14];
+    reader.read_exact(&mut handshake).await?;
+    if &handshake != b"JDWP-Handshake" {
+        return Err(io::Error::new(io::ErrorKind::InvalidData, "Invalid JDWP handshake"));
+    }
+    writer.write_all(&handshake).await?;
+    let mut released = false;
+    let mut held: Vec<Vec<u8>> = Vec::new();
+    loop {
+        // Retain the in-flight read when attach completes, including partial packets.
+        let read = packet(reader);
+        tokio::pin!(read);
+        let packet = tokio::select! {
+            result = &mut read => result?,
+            result = &mut ready, if !released => {
+                result.map_err(|_| io::Error::new(io::ErrorKind::ConnectionAborted, "Kotlin attach cancelled"))?;
+                released = true;
+                for packet in held.drain(..) {
+                    writer.write_all(&packet).await?;
+                }
+                read.await?
+            }
+        };
+        // JDWP VirtualMachine.Resume (1/9), ThreadReference.Resume (11/3).
+        // Other commands must proceed: attach itself queries threads and installs requests.
+        if !released && packet[8] == 0 && matches!((packet[9], packet[10]), (1, 9) | (11, 3)) {
+            if held.len() >= 1024 {
+                return Err(io::Error::new(io::ErrorKind::InvalidData, "Too many pending JDWP resumes"));
+            }
+            held.push(packet);
+        } else {
+            writer.write_all(&packet).await?;
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn command(id: u8, set: u8, cmd: u8) -> Vec<u8> {
+        vec![0, 0, 0, 11, 0, 0, 0, id, 0, set, cmd]
+    }
+
+    #[tokio::test]
+    async fn holds_resumes_but_allows_setup_and_preserves_partial_reads() {
+        let (mut adapter, mut reader) = tokio::io::duplex(4096);
+        let (mut writer, mut jvm) = tokio::io::duplex(4096);
+        let (release, ready) = oneshot::channel();
+        let task = tokio::spawn(async move { forward(&mut reader, &mut writer, ready).await });
+        adapter.write_all(b"JDWP-Handshake").await.unwrap();
+        let mut handshake = [0; 14];
+        jvm.read_exact(&mut handshake).await.unwrap();
+        assert_eq!(&handshake, b"JDWP-Handshake");
+        let resume = command(1, 1, 9);
+        let thread_resume = command(2, 11, 3);
+        let setup = command(3, 1, 4);
+        adapter.write_all(&resume).await.unwrap();
+        adapter.write_all(&thread_resume).await.unwrap();
+        adapter.write_all(&setup).await.unwrap();
+        assert_eq!(packet(&mut jvm).await.unwrap(), setup);
+        let next = command(4, 1, 9);
+        adapter.write_all(&next[..6]).await.unwrap();
+        release.send(()).unwrap();
+        assert_eq!(packet(&mut jvm).await.unwrap(), resume);
+        assert_eq!(packet(&mut jvm).await.unwrap(), thread_resume);
+        adapter.write_all(&next[6..]).await.unwrap();
+        assert_eq!(packet(&mut jvm).await.unwrap(), next);
+        drop(adapter);
+        assert!(task.await.unwrap().is_err());
+    }
+
+    #[tokio::test]
+    async fn dropping_session_closes_relay() {
+        let (relay, port) = StartupRelay::start("127.0.0.1".into(), 1).await.unwrap();
+        let mut adapter = TcpStream::connect(("127.0.0.1", port)).await.unwrap();
+        drop(relay);
+        let result = tokio::time::timeout(Duration::from_secs(1), adapter.read_u8()).await.unwrap();
+        assert!(result.is_err());
+    }
+
+    #[tokio::test]
+    async fn rejects_invalid_packet_lengths() {
+        for len in [0_u32, 10, 16 * 1024 * 1024 + 1] {
+            let mut bytes = command(1, 1, 9);
+            bytes[..4].copy_from_slice(&len.to_be_bytes());
+            assert_eq!(packet(&mut bytes.as_slice()).await.unwrap_err().kind(), io::ErrorKind::InvalidData);
+        }
+    }
+}
@@ -13,6 +13,8 @@ pub mod attach;
 mod cargo;
 pub mod connection;
 pub mod jdwp;
+pub mod kotlin;
+mod kotlin_jdwp;
 mod session;

 use adapter::{AdapterLauncher, AdapterSpec, ProcessLauncher};
@@ -563,6 +565,14 @@ impl DebugManager {
        let dbg = adapter::find_config(&self.languages, &config.adapter)
            .ok_or_else(|| IdeError::unavailable(format!("unknown debug adapter `{}`", config.adapter)))?;
        let mut spec = adapter::resolve(&dbg, cwd.clone());
+        if config.adapter == kotlin::ADAPTER
+            && let Some(home) = arguments
+                .as_object_mut()
+                .and_then(|o| o.remove("__adapterJavaHome"))
+                .and_then(|v| v.as_str().map(str::to_owned))
+        {
+            spec.env.push(("JAVA_HOME".into(), home));
+        }
        if let Some(command) = custom_command(&spec.command) {
            spec.command = command;
        }
@@ -687,6 +697,14 @@ impl DebugManager {
        };
        let session =
            Arc::new(Session::new(id, owner, name, adapter_name, parent, request, conn, spec, io.port, io.child));
+        if let Some(mut output) = io.program_output {
+            let session = session.clone();
+            tokio::spawn(async move {
+                while let Some((category, output)) = output.recv().await {
+                    session.emit(ide_core::event::DebugEvent::Output { category: category.into(), output });
+                }
+            });
+        }
        self.sessions.lock().insert(id, session.clone());
        self.order.lock().push(id);
        // Announced before the event loop runs, so it precedes every adapter event.
@@ -722,7 +740,19 @@ impl DebugManager {
        }
    }

-    async fn configure(&self, s: &Arc<Session>, arguments: Value) -> IdeResult<()> {
+    async fn configure(&self, s: &Arc<Session>, mut arguments: Value) -> IdeResult<()> {
+        if s.adapter == kotlin::ADAPTER {
+            let project = arguments
+                .get("projectRoot")
+                .and_then(Value::as_str)
+                .map(PathBuf::from)
+                .unwrap_or_else(|| s.spec.cwd.clone());
+            let mirror = tokio::task::spawn_blocking(move || kotlin::SourceMirror::create(&project))
+                .await
+                .map_err(|e| IdeError::internal(e.to_string()))??;
+            arguments["projectRoot"] = json!(mirror.root());
+            *s.kotlin_mirror.lock() = Some(mirror);
+        }
        let caps = s
            .conn
            .request_timeout(
@@ -749,8 +779,32 @@ impl DebugManager {
            .await?;
        *s.caps.lock() = if caps.is_object() { caps } else { json!({}) };

+        // The Kotlin adapter ignores the resolved classpath and project runtime on launch.
+        let request = if s.adapter == kotlin::ADAPTER && s.request == "launch" {
+            session::start_kotlin_debuggee(s, &mut arguments).await?;
+            "attach"
+        } else {
+            &s.request
+        };
+        if s.adapter == kotlin::ADAPTER {
+            let host = arguments
+                .get("hostName")
+                .and_then(Value::as_str)
+                .ok_or_else(|| IdeError::invalid("Missing Kotlin JDWP host"))?
+                .to_owned();
+            let port = arguments
+                .get("port")
+                .and_then(Value::as_u64)
+                .and_then(|p| u16::try_from(p).ok())
+                .filter(|p| *p != 0)
+                .ok_or_else(|| IdeError::invalid("Invalid Kotlin JDWP port"))?;
+            let (relay, port) = kotlin_jdwp::StartupRelay::start(host, port).await?;
+            *s.kotlin_relay.lock() = Some(relay);
+            arguments["hostName"] = json!("127.0.0.1");
+            arguments["port"] = json!(port);
+        }
        // Many adapters answer `launch` only after `configurationDone`, so don't wait for it yet.
-        let launch = s.conn.send_request(&s.request, arguments)?;
+        let launch = s.conn.send_request(request, arguments)?;
        let mut launch = Box::pin(async move { launch.await.unwrap_or(Err(DapError::Closed)) });
        let mut initialized = s.initialized.subscribe();
        let mut launch_result = None;
@@ -780,6 +834,7 @@ impl DebugManager {
                        s.emit(ide_core::event::DebugEvent::BreakpointsChanged { path: path.into() });
                    }
                }
+                Err(e) if s.adapter == kotlin::ADAPTER => return Err(e.into()),
                Err(e) => tracing::debug!("setBreakpoints for {} failed: {e}", path.display()),
            }
        }
@@ -802,7 +857,11 @@ impl DebugManager {
            let _ = self.send_exception_breakpoints(s).await;
        }
        if s.supports("supportsConfigurationDoneRequest") {
-            s.conn.request_timeout("configurationDone", Value::Null, REQUEST_TIMEOUT).await?;
+            if s.adapter == kotlin::ADAPTER {
+                drop(s.conn.send_request("configurationDone", json!({}))?);
+            } else {
+                s.conn.request_timeout("configurationDone", Value::Null, REQUEST_TIMEOUT).await?;
+            }
        }
        s.configured.store(true, Ordering::Release);
        if launch_result.is_none() {
@@ -813,6 +872,9 @@ impl DebugManager {
                Err(_) => return Err(DapError::Timeout(s.request.clone()).into()),
            }
        }
+        if let Some(relay) = s.kotlin_relay.lock().as_mut() {
+            relay.release();
+        }
        Ok(())
    }

@@ -869,6 +931,7 @@ impl DebugManager {
                Ok(states) => {
                    result.get_or_insert(states);
                }
+                Err(e) if s.adapter == kotlin::ADAPTER => return Err(e.into()),
                Err(e) => tracing::debug!("setBreakpoints on session {} failed: {e}", s.id.0),
            }
        }
@@ -886,6 +949,23 @@ impl DebugManager {
        Ok(states)
    }

+    /// Refresh fallback copies after an editor save.
+    pub async fn refresh_source_mirrors(&self, owner: &str) -> IdeResult<()> {
+        let sessions: Vec<_> = self.sessions.lock().values().filter(|s| s.owner.key == owner).cloned().collect();
+        tokio::task::spawn_blocking(move || {
+            for s in sessions {
+                if let Some(mirror) = s.kotlin_mirror.lock().as_mut()
+                    && let Err(e) = mirror.refresh()
+                {
+                    tracing::warn!("Could not refresh Kotlin debug sources: {e}");
+                }
+            }
+            Ok(())
+        })
+        .await
+        .map_err(|e| IdeError::internal(e.to_string()))?
+    }
+
    /// Last known verification states of a file's breakpoints (after `BreakpointsChanged`).
    pub fn breakpoint_states(&self, path: &Path) -> Vec<BreakpointState> {
        self.states.lock().get(path).cloned().unwrap_or_default()
@@ -54,6 +54,8 @@ pub(crate) struct Session {
    /// Resolved path → the path as the IDE knows it, for adapters given resolved paths.
    resolved_paths: Mutex<HashMap<PathBuf, PathBuf>>,
    progress: Mutex<HashMap<String, TaskId>>,
+    pub kotlin_relay: Mutex<Option<crate::kotlin_jdwp::StartupRelay>>,
+    pub kotlin_mirror: Mutex<Option<crate::kotlin::SourceMirror>>,
 }

 /// Adapters that only match files by their resolved path: Godot maps a script to
@@ -95,6 +97,8 @@ impl Session {
            breakpoint_ids: Mutex::new(HashMap::new()),
            resolved_paths: Mutex::new(HashMap::new()),
            progress: Mutex::new(HashMap::new()),
+            kotlin_relay: Mutex::new(None),
+            kotlin_mirror: Mutex::new(None),
        }
    }

@@ -104,6 +108,14 @@ impl Session {

    /// `path` as sent to the adapter (resolved for [`RESOLVES_PATHS`] adapters).
    pub fn adapter_path(&self, path: &Path) -> PathBuf {
+        if let Some(path) = self.kotlin_mirror.lock().as_ref().and_then(|m| m.adapter_path(path)) {
+            return path;
+        }
+        if self.adapter == "java-debug" {
+            let native = java_source_path(&path.to_string_lossy());
+            self.resolved_paths.lock().insert(native.clone(), path.to_path_buf());
+            return native;
+        }
        if !RESOLVES_PATHS.contains(&self.adapter.as_str()) {
            return path.to_path_buf();
        }
@@ -118,7 +130,14 @@ impl Session {

    /// A path from the adapter as the IDE knows it (undoes [`Session::adapter_path`]).
    pub fn client_path(&self, path: &str) -> Option<PathBuf> {
-        self.resolved_paths.lock().get(Path::new(path)).cloned()
+        if let Some(real) = self.kotlin_mirror.lock().as_ref().and_then(|m| m.client_path(Path::new(path))) {
+            return Some(real);
+        }
+        let key = if self.adapter == "java-debug" { java_source_path(path) } else { PathBuf::from(path) };
+        self.resolved_paths.lock().get(&key).cloned().or_else(|| {
+            (self.adapter == "java-debug" && is_windows_source_path(path))
+                .then(|| PathBuf::from(path.replace('\\', "/")))
+        })
    }

    pub fn supports(&self, cap: &str) -> bool {
@@ -236,6 +255,7 @@ impl Session {

    /// Kills the adapter and every debuggee we started.
    pub fn kill_processes(&self) {
+        self.kotlin_relay.lock().take();
        if let Some(mut c) = self.adapter_process.lock().take() {
            let _ = c.start_kill();
        }
@@ -245,6 +265,19 @@ impl Session {
    }
 }

+// java-debug treats a forward-slash drive path as a URI (scheme "C").
+// Keep DAP path mode, but use native Windows separators for Java source lookup.
+fn is_windows_source_path(path: &str) -> bool {
+    let bytes = path.as_bytes();
+    (bytes.len() >= 3 && bytes[0].is_ascii_alphabetic() && bytes[1] == b':' && matches!(bytes[2], b'/' | b'\\'))
+        || path.starts_with("//")
+        || path.starts_with(r"\\")
+}
+
+fn java_source_path(path: &str) -> PathBuf {
+    if is_windows_source_path(path) { PathBuf::from(path.replace('/', r"\")) } else { PathBuf::from(path) }
+}
+
 fn with_conditions(v: &mut Value, condition: Option<&str>, hit_condition: Option<&str>) {
    if let Some(c) = condition.filter(|c| !c.trim().is_empty()) {
        v["condition"] = c.into();
@@ -297,7 +330,10 @@ pub(crate) async fn event_loop(
    }
 }

-async fn on_event(mgr: &Arc<DebugManager>, s: &Arc<Session>, event: &str, body: Value) {
+async fn on_event(mgr: &Arc<DebugManager>, s: &Arc<Session>, event: &str, mut body: Value) {
+    if let Some(mirror) = s.kotlin_mirror.lock().as_ref() {
+        mirror.translate(&mut body);
+    }
    let int = |k: &str| body.get(k).and_then(Value::as_i64);
    let str_ = |k: &str| body.get(k).and_then(Value::as_str).map(str::to_owned);
    match event {
@@ -486,3 +522,74 @@ fn forward_output<R: AsyncRead + Unpin + Send + 'static>(s: &Session, mut stream
        }
    });
 }
+
+/// Launch with the IDE's resolved runtime and classpath; the adapter only attaches.
+pub(crate) async fn start_kotlin_debuggee(s: &Arc<Session>, args: &mut Value) -> ide_core::IdeResult<()> {
+    use tokio::io::{AsyncBufReadExt, BufReader};
+    let port = crate::adapter::free_port()?;
+    let java = args.get("javaExec").and_then(Value::as_str).unwrap_or("java");
+    let strings = |key: &str| -> Vec<String> {
+        args.get(key)
+            .and_then(Value::as_array)
+            .map(|a| a.iter().filter_map(Value::as_str).map(str::to_owned).collect())
+            .unwrap_or_default()
+    };
+    let classpath =
+        std::env::join_paths(strings("classPaths")).map_err(|e| ide_core::IdeError::invalid(e.to_string()))?;
+    let mut cmd = tokio::process::Command::new(java);
+    ide_core::process::prepare(cmd.as_std_mut());
+    cmd.args(strings("vmArguments"))
+        .arg(format!("-agentlib:jdwp=transport=dt_socket,server=y,suspend=y,address=127.0.0.1:{port}"))
+        .arg("-cp")
+        .arg(classpath);
+    let modules = strings("modulePaths");
+    if !modules.is_empty() {
+        cmd.arg("--module-path")
+            .arg(std::env::join_paths(modules).map_err(|e| ide_core::IdeError::invalid(e.to_string()))?);
+    }
+    cmd.arg(
+        args.get("mainClass")
+            .and_then(Value::as_str)
+            .ok_or_else(|| ide_core::IdeError::invalid("Missing Kotlin main class"))?,
+    )
+    .args(strings("programArgs"))
+    .current_dir(&s.spec.cwd)
+    .envs(ide_core::process::shell_env())
+    .stdin(Stdio::null())
+    .stdout(Stdio::piped())
+    .stderr(Stdio::piped())
+    .kill_on_drop(true);
+    if let Some(env) = args.get("env").and_then(Value::as_object) {
+        for (k, v) in env {
+            if let Some(v) = v.as_str() {
+                cmd.env(k, v);
+            }
+        }
+    }
+    let mut child = cmd.spawn()?;
+    if let Some(err) = child.stderr.take() {
+        forward_output(s, err, "stderr");
+    }
+    let mut stdout =
+        BufReader::new(child.stdout.take().ok_or_else(|| ide_core::IdeError::internal("Missing JVM stdout"))?);
+    tokio::time::timeout(Duration::from_secs(15), async {
+        loop {
+            let mut line = String::new();
+            if stdout.read_line(&mut line).await? == 0 {
+                return Err(ide_core::IdeError::unavailable("JVM exited before starting its debug listener"));
+            }
+            if line.contains("Listening for transport dt_socket") {
+                return Ok(());
+            }
+            s.emit(DebugEvent::Output { category: "stdout".into(), output: line });
+        }
+    })
+    .await
+    .map_err(|_| ide_core::IdeError::unavailable("JVM did not start its debug listener"))??;
+    forward_output(s, stdout, "stdout");
+    s.debuggees.lock().push(child);
+    args["hostName"] = json!("127.0.0.1");
+    args["port"] = json!(port);
+    args["timeout"] = json!(10000);
+    Ok(())
+}
@@ -15,6 +15,8 @@ struct Script {
    run_in_terminal: Option<Vec<String>>,
    /// Send a `startDebugging` reverse request (child session) when a non-child `launch` arrives.
    start_debugging: bool,
+    ignore_configuration_done: bool,
+    source_path: Option<String>,
 }

 struct FakeLauncher {
@@ -30,7 +32,14 @@ impl AdapterLauncher for FakeLauncher {
        tokio::spawn(fake_adapter(server, log, script));
        let (r, w) = tokio::io::split(client);
        Box::pin(async move {
-            Ok(AdapterIo { reader: Box::new(r), writer: Box::new(w), child: None, port: None, stderr: Arc::default() })
+            Ok(AdapterIo {
+                reader: Box::new(r),
+                writer: Box::new(w),
+                child: None,
+                port: None,
+                stderr: Arc::default(),
+                program_output: None,
+            })
        })
    }
 }
@@ -130,7 +139,9 @@ async fn fake_adapter<S: AsyncRead + AsyncWrite + Unpin + Send + 'static>(stream
                ok!(msg, json!({"value": format!("{}!", msg["arguments"]["value"].as_str().unwrap()), "type": "int"}))
            }
            "configurationDone" => {
-                ok!(msg, Value::Null);
+                if !script.ignore_configuration_done {
+                    ok!(msg, Value::Null);
+                }
                if let Some(l) = pending_launch.take() {
                    send!(json!({"type": "response", "request_seq": l, "command": "launch", "success": true}));
                }
@@ -139,14 +150,14 @@ async fn fake_adapter<S: AsyncRead + AsyncWrite + Unpin + Send + 'static>(stream
                    json!({"type": "event", "event": "stopped", "body": {"reason": "breakpoint", "threadId": 1, "allThreadsStopped": true}})
                );
                send!(
-                    json!({"type": "event", "event": "breakpoint", "body": {"reason": "changed", "breakpoint": {"id": 1, "verified": false, "message": "moved", "line": 9}}})
+                    json!({"type": "event", "event": "breakpoint", "body": {"reason": "changed", "breakpoint": {"id": 1, "verified": false, "message": "moved", "line": 9, "source": {"path": script.source_path}}}})
                );
            }
            "threads" => ok!(msg, json!({"threads": [{"id": 1, "name": "MainThread"}]})),
            "stackTrace" => ok!(
                msg,
                json!({"stackFrames": [
-                    {"id": 10, "name": "main", "line": 5, "column": 3, "source": {"path": "/p/a.py"}},
+                    {"id": 10, "name": "main", "line": 5, "column": 3, "source": {"path": script.source_path.as_deref().unwrap_or("/p/a.py")}},
                    {"id": 11, "name": "lib", "line": 1, "column": 1, "source": {"path": "/usr/lib/x.py", "presentationHint": "deemphasize"}},
                ]})
            ),
@@ -893,6 +904,8 @@ fn godot_registry(port: u16, command: &str, args: &[&str]) -> Arc<LanguageRegist
        block_comment: None,
        indent: None,
        ui_mode: None,
+        framework_ui_modes: Vec::new(),
+        formatter: None,
        tree_sitter: None,
        language_servers: vec![],
        debugger: Some(ide_language::DebuggerConfig {
@@ -1015,3 +1028,122 @@ fn root_and_address_placeholders() {
    assert_eq!(adapter::parse_address("[::1]:6006"), Some(("::1".into(), 6006)));
    assert_eq!(adapter::parse_address("6006"), None);
 }
+
+#[tokio::test]
+async fn kotlin_configures_without_configuration_done_response() {
+    let h = harness(Script { ignore_configuration_done: true, ..Default::default() });
+    let project = tempfile::tempdir().unwrap();
+    let path = project.path().join("Main.kt");
+    std::fs::write(&path, "package org.example\nfun main() {}\n").unwrap();
+    h.manager.set_breakpoints(path.clone(), vec![bp(1)]).await.unwrap();
+    let mut config = config();
+    config.adapter = kotlin::ADAPTER.into();
+    config.request = "attach".into();
+    config.cwd = Some(project.path().to_owned().into());
+    config.extra_json = Some(json!({"projectRoot": project.path(), "hostName": "127.0.0.1", "port": 5005}).to_string());
+    let id = tokio::time::timeout(Duration::from_secs(2), h.start(config)).await.unwrap().unwrap();
+    let root = PathBuf::from(h.request("attach")["arguments"]["projectRoot"].as_str().unwrap());
+    assert!(!root.starts_with(project.path()));
+    let request = h.request("setBreakpoints");
+    assert_eq!(request["arguments"]["source"]["name"], "Main.kt");
+    let mapped = PathBuf::from(request["arguments"]["source"]["path"].as_str().unwrap());
+    assert!(mapped.starts_with(&root));
+    assert!(mapped.is_file());
+    assert_eq!(h.manager.session(id).unwrap().client_path(mapped.to_str().unwrap()), Some(path));
+    h.manager.stop(id).await.unwrap();
+}
+
+/// Requires a compiled no-delay reporter fixture (Main.kt, package org.example,
+/// loop at line 5, println(i) at line 6), and the unmodified official adapter.
+/// KOTLIN_PROBE_CONFIG is a LaunchConfig JSON file; KOTLIN_PROBE_ADAPTER is its executable.
+#[tokio::test]
+#[ignore = "requires official Kotlin adapter and compiled reporter fixture"]
+async fn kotlin_official_release_ten_no_delay_runs() {
+    let config: LaunchConfig = serde_json::from_slice(
+        &std::fs::read(std::env::var("KOTLIN_PROBE_CONFIG").expect("KOTLIN_PROBE_CONFIG")).unwrap(),
+    )
+    .unwrap();
+    let adapter = std::env::var("KOTLIN_PROBE_ADAPTER").expect("KOTLIN_PROBE_ADAPTER");
+    let source = PathBuf::from(config.cwd.clone().unwrap()).join("src/main/kotlin/Main.kt");
+    for run in 1..=10 {
+        let (owner, events) = recording_owner("kotlin-probe");
+        let manager = DebugManager::new(Arc::new(LanguageRegistry::from_configs(Vec::new())));
+        let h = Harness { manager, owner, events, log: Arc::default() };
+        h.manager.set_breakpoints(source.clone(), vec![bp(5)]).await.unwrap();
+        let id = h.manager.start_with(config.clone(), h.owner.clone(), |_| Some(adapter.clone())).await.unwrap();
+        let stopped = h.wait_event(|e| matches!(e, DebugEvent::Stopped { reason, .. } if reason == "breakpoint")).await;
+        let DebugEvent::Stopped { thread_id, .. } = stopped else { unreachable!() };
+        let frames = h.manager.stack_trace(id, thread_id).await.unwrap();
+        assert_eq!(frames[0].line, 5);
+        assert_eq!(frames[0].path.as_deref(), Some(source.as_path()));
+        let scopes = h.manager.scopes(id, frames[0].id).await.unwrap();
+        let mut variables = Vec::new();
+        for scope in scopes {
+            variables.extend(h.manager.variables(id, scope.variables_reference).await.unwrap());
+        }
+        assert!(variables.iter().any(|v| v.name == "i" && v.value == "0"));
+        h.manager.step(id, thread_id, StepKind::Over).await.unwrap();
+        h.wait_event(|e| matches!(e, DebugEvent::Stopped { reason, .. } if reason == "step")).await;
+        let frames = h.manager.stack_trace(id, thread_id).await.unwrap();
+        assert_eq!(frames[0].line, 4);
+        h.manager.stop(id).await.unwrap();
+        println!("Run {run}/10: breakpoint Main.kt:6, i=0, step Main.kt:5; stopped");
+    }
+}
+
+#[tokio::test]
+async fn java_windows_source_paths_for_launch_and_attach() {
+    for request in ["launch", "attach"] {
+        for (client, native, returned) in [
+            ("C:/work/Main.java", r"C:\work\Main.java", r"C:\work\Main.java"),
+            ("C:/work/Main.java", r"C:\work\Main.java", "C:/work/Main.java"),
+            (r"c:\work\Main.java", r"c:\work\Main.java", "c:/work/Main.java"),
+            (r"D:/my project\Main.java", r"D:\my project\Main.java", r"D:\my project\Main.java"),
+            ("//server/share/Main.java", r"\\server\share\Main.java", "//server/share/Main.java"),
+            (r"\\server\share/Main.java", r"\\server\share\Main.java", "//server/share/Main.java"),
+            ("/work/Main.java", "/work/Main.java", "/work/Main.java"),
+        ] {
+            let h = harness(Script { source_path: Some(returned.into()), ..Script::default() });
+            let path = PathBuf::from(client);
+            h.manager.set_breakpoints(path.clone(), vec![bp(4)]).await.unwrap();
+            let mut cfg = config();
+            cfg.adapter = "java-debug".into();
+            cfg.request = request.into();
+            let id = h.start(cfg).await.unwrap();
+            assert_eq!(h.request("initialize")["arguments"]["pathFormat"], "path");
+            assert_eq!(h.request("setBreakpoints")["arguments"]["source"]["path"], native);
+            let commands = h.commands();
+            assert!(
+                commands.iter().position(|c| c == "setBreakpoints").unwrap()
+                    < commands.iter().position(|c| c == "configurationDone").unwrap()
+            );
+            let frames = h.manager.stack_trace(id, 1).await.unwrap();
+            assert_eq!(frames[0].path.as_deref(), Some(path.as_path()));
+            h.wait_event(|e| {
+                matches!(e, DebugEvent::BreakpointsChanged { path: p } if p.as_ref() == path.as_path())
+                    && h.manager.breakpoint_states(&path)[0].message.as_deref() == Some("moved")
+            })
+            .await;
+            assert_eq!(h.manager.breakpoint_states(&path)[0].message.as_deref(), Some("moved"));
+            h.manager.stop(id).await.unwrap();
+        }
+    }
+}
+
+#[tokio::test]
+async fn java_stack_frames_without_breakpoints_normalize_windows_paths() {
+    for (returned, expected) in [
+        (r"C:\work\Other.java", "C:/work/Other.java"),
+        (r"\\server\share\Other.java", "//server/share/Other.java"),
+        ("C:/work/Other.java", "C:/work/Other.java"),
+        ("/work/Other.java", "/work/Other.java"),
+    ] {
+        let h = harness(Script { source_path: Some(returned.into()), ..Script::default() });
+        let mut cfg = config();
+        cfg.adapter = "java-debug".into();
+        let id = h.start(cfg).await.unwrap();
+        let frames = h.manager.stack_trace(id, 1).await.unwrap();
+        assert_eq!(frames[0].path.as_deref(), Some(PathBuf::from(expected).as_path()));
+        h.manager.stop(id).await.unwrap();
+    }
+}
@@ -16,6 +16,9 @@ tracing.workspace = true
 parking_lot.workspace = true
 futures.workspace = true
 sqlx.workspace = true
+tiberius.workspace = true
+bb8.workspace = true
+tokio-util = { workspace = true, features = ["compat"] }
 dirs.workspace = true
 ide-ssh.workspace = true

@@ -5,6 +5,9 @@
 //! whatever its type.

 use crate::source::{DataSource, DbDriver, DbSslMode};
+use bb8::ManageConnection;
+use bb8::Pool as Bb8Pool;
+use futures::StreamExt;
 use ide_core::{CancellationToken, IdeError, IdeResult, error::ErrorKind};
 use serde::{Deserialize, Serialize};
 use specta::Type;
@@ -44,10 +47,65 @@ pub struct QueryResult {
    pub execution_ms: f64,
 }

+// Keep an empty slot when a connection is discarded after cancellation or rollback failure.
+pub struct MssqlConnectionManager(tiberius::Config);
+
+type MssqlClient = tiberius::Client<tokio_util::compat::Compat<tokio::net::TcpStream>>;
+
+pub struct MssqlConnection(Option<MssqlClient>);
+
+impl std::ops::Deref for MssqlConnection {
+    type Target = MssqlClient;
+    fn deref(&self) -> &Self::Target {
+        self.0.as_ref().expect("live SQL Server connection")
+    }
+}
+
+impl std::ops::DerefMut for MssqlConnection {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        self.0.as_mut().expect("live SQL Server connection")
+    }
+}
+
+impl ManageConnection for MssqlConnectionManager {
+    type Connection = MssqlConnection;
+    type Error = tiberius::error::Error;
+
+    async fn connect(&self) -> Result<Self::Connection, Self::Error> {
+        use tokio_util::compat::TokioAsyncWriteCompatExt;
+
+        let tcp = tokio::net::TcpStream::connect(self.0.get_addr()).await?;
+        tcp.set_nodelay(true)?;
+        let client = match MssqlClient::connect(self.0.clone(), tcp.compat_write()).await {
+            // Preserve the single redirect supported by the previous pool adapter.
+            Err(tiberius::error::Error::Routing { host, port }) => {
+                let mut config = self.0.clone();
+                config.host(host);
+                config.port(port);
+                let tcp = tokio::net::TcpStream::connect(config.get_addr()).await?;
+                tcp.set_nodelay(true)?;
+                MssqlClient::connect(config, tcp.compat_write()).await?
+            }
+            result => result?,
+        };
+        Ok(MssqlConnection(Some(client)))
+    }
+
+    async fn is_valid(&self, conn: &mut Self::Connection) -> Result<(), Self::Error> {
+        conn.simple_query("SELECT 1").await?.into_results().await?;
+        Ok(())
+    }
+
+    fn has_broken(&self, conn: &mut Self::Connection) -> bool {
+        conn.0.is_none()
+    }
+}
+
 pub enum Pool {
    Sqlite(SqlitePool),
    Postgres(PgPool),
    Mysql(MySqlPool),
+    SqlServer(Bb8Pool<MssqlConnectionManager>),
 }

 /// Runs `$body` with `$p` bound to the concrete pool of each driver.
@@ -57,6 +115,7 @@ macro_rules! with_pool {
            Pool::Sqlite($p) => $body,
            Pool::Postgres($p) => $body,
            Pool::Mysql($p) => $body,
+            Pool::SqlServer(_) => unreachable!(),
        }
    };
 }
@@ -79,6 +138,129 @@ pub(crate) fn db_err(e: sqlx::Error) -> IdeError {
    }
 }

+pub(crate) fn mssql_err(e: tiberius::error::Error) -> IdeError {
+    match &e {
+        tiberius::error::Error::Server(d) => {
+            let code = d.code();
+            // Wrong login: SQL Server 18456.
+            let auth = matches!(code, 18452 | 18456 | 18470);
+            IdeError::new(
+                if auth { ErrorKind::PermissionDenied } else { ErrorKind::InvalidInput },
+                format!("[{code}] {}", d.message()),
+            )
+        }
+        tiberius::error::Error::Io { .. } | tiberius::error::Error::Tls(_) => {
+            IdeError::new(ErrorKind::Io, e.to_string())
+        }
+        _ => IdeError::new(ErrorKind::Protocol, e.to_string()),
+    }
+}
+
+fn mssql_pool_err(e: bb8::RunError<tiberius::error::Error>) -> IdeError {
+    match e {
+        bb8::RunError::User(e) => mssql_err(e),
+        bb8::RunError::TimedOut => IdeError::new(ErrorKind::Io, "timed out connecting to the database"),
+    }
+}
+
+const DAYS_1900_01_01: i64 = 693_595;
+
+/// Formats a proleptic Gregorian date given days since `0001-01-01`.
+fn format_date(days: i64) -> String {
+    let z = days + 306;
+    let era = z.div_euclid(146_097);
+    let doe = z.rem_euclid(146_097);
+    let yoe = (doe - doe / 1460 + doe / 36524 - doe / 146_096) / 365;
+    let y = yoe + era * 400;
+    let doy = doe - (365 * yoe + yoe / 4 - yoe / 100);
+    let mp = (5 * doy + 2) / 153;
+    let d = doy - (153 * mp + 2) / 5 + 1;
+    let m = if mp < 10 { mp + 3 } else { mp - 9 };
+    let year = if m <= 2 { y + 1 } else { y };
+    format!("{year:04}-{m:02}-{d:02}")
+}
+
+fn format_hms(secs: u64, frac: u64, scale: u8) -> String {
+    let (h, m, s) = (secs / 3600, (secs / 60) % 60, secs % 60);
+    if scale == 0 || frac == 0 {
+        format!("{h:02}:{m:02}:{s:02}")
+    } else {
+        let frac = format!("{frac:0width$}", width = usize::from(scale));
+        format!("{h:02}:{m:02}:{s:02}.{}", frac.trim_end_matches('0'))
+    }
+}
+
+fn format_time(t: tiberius::time::Time) -> String {
+    let scale = t.scale().min(7);
+    let div = 10u64.pow(u32::from(scale));
+    format_hms(t.increments() / div, t.increments() % div, scale)
+}
+
+fn format_numeric(n: tiberius::numeric::Numeric) -> String {
+    let scale = u32::from(n.scale());
+    if scale == 0 {
+        return n.value().to_string();
+    }
+    let sign = if n.value() < 0 { "-" } else { "" };
+    let abs = n.value().unsigned_abs();
+    let div = 10u128.pow(scale);
+    format!("{sign}{}.{:0width$}", abs / div, abs % div, width = scale as usize)
+}
+
+fn tiberius_cell(cell: &tiberius::ColumnData<'_>, ty: tiberius::ColumnType) -> Option<String> {
+    use tiberius::ColumnData as C;
+    match cell {
+        C::U8(v) => v.map(|v| v.to_string()),
+        C::I16(v) => v.map(|v| v.to_string()),
+        C::I32(v) => v.map(|v| v.to_string()),
+        C::I64(v) => v.map(|v| v.to_string()),
+        C::F32(v) => v.map(|v| v.to_string()),
+        C::F64(v) if matches!(ty, tiberius::ColumnType::Money | tiberius::ColumnType::Money4) => {
+            // Beyond ~9e11, money precision is limited by the driver's f64 decoding.
+            v.map(|v| format!("{:.4}", v))
+        }
+        C::F64(v) => v.map(|v| v.to_string()),
+        C::Bit(v) => v.map(|v| v.to_string()),
+        C::String(v) => v.as_deref().map(str::to_owned),
+        C::Guid(v) => v.map(|v| v.to_string()),
+        C::Binary(v) => v.as_deref().map(hex),
+        C::Numeric(v) => v.map(format_numeric),
+        C::Xml(v) => v.as_deref().map(|x| x.as_ref().to_owned()),
+        C::Date(v) => v.map(|d| format_date(i64::from(d.days()))),
+        C::Time(v) => v.map(format_time),
+        C::DateTime(v) => v.map(|dt| {
+            let ms = (u64::from(dt.seconds_fragments()) * 1000 + 150) / 300;
+            format!("{} {}", format_date(DAYS_1900_01_01 + i64::from(dt.days())), format_hms(ms / 1000, ms % 1000, 3))
+        }),
+        C::SmallDateTime(v) => v.map(|dt| {
+            let secs = u64::from(dt.seconds_fragments()) * 60;
+            format!("{} {}", format_date(DAYS_1900_01_01 + i64::from(dt.days())), format_hms(secs, 0, 0))
+        }),
+        C::DateTime2(v) => {
+            v.map(|dt| format!("{} {}", format_date(i64::from(dt.date().days())), format_time(dt.time())))
+        }
+        C::DateTimeOffset(v) => v.map(|dto| {
+            let dt = dto.datetime2();
+            let t = dt.time();
+            let scale = t.scale().min(7);
+            let div = 10u64.pow(u32::from(scale));
+            let utc_secs = i64::from(dt.date().days()) * 86_400 + (t.increments() / div) as i64;
+            let local_secs = utc_secs + i64::from(dto.offset()) * 60;
+            let days = local_secs.div_euclid(86_400);
+            let secs = local_secs.rem_euclid(86_400) as u64;
+            let sign = if dto.offset() < 0 { '-' } else { '+' };
+            let off = dto.offset().unsigned_abs();
+            format!(
+                "{} {}{sign}{:02}:{:02}",
+                format_date(days),
+                format_hms(secs, t.increments() % div, scale),
+                off / 60,
+                off % 60
+            )
+        }),
+    }
+}
+
 fn hex(bytes: &[u8]) -> String {
    let mut s = String::with_capacity(2 + bytes.len() * 2);
    s.push_str("0x");
@@ -197,6 +379,37 @@ macro_rules! fetch {
 /// Columns, rows, rows affected, more rows beyond the limit, time of the first answer.
 type Fetched = (Vec<ResultColumn>, Vec<Vec<Option<String>>>, Option<u64>, bool, Option<Instant>);

+async fn mssql_command(conn: &mut MssqlClient, sql: &str) -> IdeResult<()> {
+    // Transaction control must be a batch: sp_executesql rejects a changed transaction count.
+    conn.simple_query(sql).await.map_err(mssql_err)?.into_results().await.map_err(mssql_err)?;
+    Ok(())
+}
+
+async fn mssql_fetch(conn: &mut MssqlClient, sql: &str, max: usize) -> IdeResult<Fetched> {
+    let mut stream = conn.simple_query(sql).await.map_err(mssql_err)?;
+    let first = Some(Instant::now());
+    let columns = stream
+        .columns()
+        .await
+        .map_err(mssql_err)?
+        .unwrap_or_default()
+        .iter()
+        .map(|col| ResultColumn { name: col.name().to_owned(), type_name: format!("{:?}", col.column_type()) })
+        .collect();
+    let mut rows = Vec::new();
+    let mut has_more = false;
+    while let Some(item) = stream.next().await {
+        if let tiberius::QueryItem::Row(row) = item.map_err(mssql_err)? {
+            if rows.len() >= max {
+                has_more = true;
+                break;
+            }
+            rows.push(row.cells().map(|(col, cell)| tiberius_cell(cell, col.column_type())).collect());
+        }
+    }
+    Ok((columns, rows, None, has_more, first))
+}
+
 /// The server-side id of a connection (to cancel its statement from another one).
 macro_rules! backend_id {
    ($conn:expr, $sql:expr) => {{
@@ -313,6 +526,7 @@ impl Pool {
            Pool::Sqlite(_) => DbDriver::Sqlite,
            Pool::Postgres(_) => DbDriver::Postgres,
            Pool::Mysql(_) => DbDriver::Mysql,
+            Pool::SqlServer(_) => DbDriver::SqlServer,
        }
    }

@@ -453,20 +667,60 @@ impl Pool {
                    .map_err(db_err)?;
                Ok(Pool::Mysql(pool))
            }
+            DbDriver::SqlServer => {
+                use tiberius::Config;
+                let mut config = Config::new();
+                config.host(&source.host);
+                config.port(source.port.unwrap_or(1433));
+                if !source.user.is_empty() {
+                    config.authentication(tiberius::AuthMethod::sql_server(
+                        source.user.clone(),
+                        password.unwrap_or_default().to_owned(),
+                    ));
+                }
+                if !source.database.is_empty() {
+                    config.database(&source.database);
+                }
+                if matches!(source.ssl, DbSslMode::Disable | DbSslMode::Prefer) {
+                    config.trust_cert();
+                }
+                let manager = MssqlConnectionManager(config);
+                let pool = bb8::Pool::builder()
+                    .max_size(MAX)
+                    .connection_timeout(timeout)
+                    .build(manager)
+                    .await
+                    .map_err(mssql_err)?;
+                let mut conn = pool.get_owned().await.map_err(mssql_pool_err)?;
+                conn.query("SELECT 1", &[]).await.map_err(mssql_err)?.into_results().await.map_err(mssql_err)?;
+                Ok(Pool::SqlServer(pool))
+            }
        }
    }

    pub async fn close(&self) {
-        with_pool!(self, p => p.close().await)
+        match self {
+            Pool::SqlServer(_) => {}
+            _ => with_pool!(self, p => p.close().await),
+        }
    }

    pub fn is_closed(&self) -> bool {
-        with_pool!(self, p => p.is_closed())
+        match self {
+            Pool::SqlServer(_) => false,
+            _ => with_pool!(self, p => p.is_closed()),
+        }
    }

    /// Runs `sql` (no row limit beyond `max`), for introspection: cells are text (see [`Cells::Text`]).
    pub async fn rows(&self, sql: &str, max: usize) -> IdeResult<Vec<Vec<Option<String>>>> {
-        let fetched: IdeResult<Fetched> = with_pool!(self, p => fetch!(p, sql, max, Cells::Text));
+        let fetched: IdeResult<Fetched> = match self {
+            Pool::SqlServer(p) => {
+                let mut conn = p.get_owned().await.map_err(mssql_pool_err)?;
+                mssql_fetch(&mut conn, sql, max).await
+            }
+            _ => with_pool!(self, p => fetch!(p, sql, max, Cells::Text)),
+        };
        Ok(fetched?.1)
    }

@@ -485,21 +739,47 @@ impl Pool {
    /// Runs `statements` in one transaction; each must change `expect_one`
    /// row when flagged (table editor submits).
    pub async fn transaction(&self, statements: &[(String, bool)]) -> IdeResult<u64> {
-        with_pool!(self, p => {
-            let mut tx = p.begin().await.map_err(db_err)?;
-            let mut total = 0;
-            for (sql, expect_one) in statements {
-                let done = sqlx::raw_sql(sqlx::AssertSqlSafe(sql.clone())).execute(&mut *tx).await.map_err(db_err)?;
-                let n = done.rows_affected();
-                // MySQL reports 0 for an UPDATE that leaves the row unchanged.
-                if *expect_one && (n > 1 || (n == 0 && !matches!(self, Pool::Mysql(_)))) {
-                    return Err(IdeError::invalid(format!("{sql}: expected to change 1 row, changed {n}; nothing was saved")));
+        match self {
+            Pool::SqlServer(p) => {
+                let mut conn = p.get_owned().await.map_err(mssql_pool_err)?;
+                let result = async {
+                    mssql_command(&mut conn, "BEGIN TRAN").await?;
+                    let mut total = 0;
+                    for (sql, expect_one) in statements {
+                        let n = conn.execute(sql, &[]).await.map_err(mssql_err)?.total();
+                        if *expect_one && n != 1 {
+                            return Err(IdeError::invalid(format!(
+                                "{sql}: expected to change 1 row, changed {n}; nothing was saved"
+                            )));
+                        }
+                        total += n;
+                    }
+                    mssql_command(&mut conn, "COMMIT TRAN").await?;
+                    Ok(total)
                }
-                total += n;
+                .await;
+                if result.is_err() && mssql_command(&mut conn, "IF @@TRANCOUNT > 0 ROLLBACK TRAN").await.is_err() {
+                    // A failed rollback must never return an open transaction to the pool.
+                    conn.0.take();
+                }
+                result
            }
-            tx.commit().await.map_err(db_err)?;
-            Ok(total)
-        })
+            _ => with_pool!(self, p => {
+                let mut tx = p.begin().await.map_err(db_err)?;
+                let mut total = 0;
+                for (sql, expect_one) in statements {
+                    let done = sqlx::raw_sql(sqlx::AssertSqlSafe(sql.clone())).execute(&mut *tx).await.map_err(db_err)?;
+                    let n = done.rows_affected();
+                    // MySQL reports 0 for an UPDATE that leaves the row unchanged.
+                    if *expect_one && (n > 1 || (n == 0 && !matches!(self, Pool::Mysql(_)))) {
+                        return Err(IdeError::invalid(format!("{sql}: expected to change 1 row, changed {n}; nothing was saved")));
+                    }
+                    total += n;
+                }
+                tx.commit().await.map_err(db_err)?;
+                Ok(total)
+            }),
+        }
    }
 }

@@ -509,6 +789,7 @@ pub enum Held {
    Sqlite(PoolConnection<Sqlite>),
    Postgres(PoolConnection<Postgres>),
    Mysql(PoolConnection<MySql>),
+    SqlServer(Box<bb8::PooledConnection<'static, MssqlConnectionManager>>),
 }

 impl Held {
@@ -517,18 +798,25 @@ impl Held {
            Pool::Sqlite(p) => Held::Sqlite(p.acquire().await.map_err(db_err)?),
            Pool::Postgres(p) => Held::Postgres(p.acquire().await.map_err(db_err)?),
            Pool::Mysql(p) => Held::Mysql(p.acquire().await.map_err(db_err)?),
+            Pool::SqlServer(p) => Held::SqlServer(Box::new(p.get_owned().await.map_err(mssql_pool_err)?)),
        })
    }

    /// Runs a statement without results (`BEGIN`, `COMMIT`, `ROLLBACK`).
    pub async fn command(&mut self, sql: &str) -> IdeResult<()> {
-        let sql = sqlx::AssertSqlSafe(sql.to_owned());
        match self {
-            Held::Sqlite(c) => sqlx::raw_sql(sql).execute(&mut **c).await.map(drop),
-            Held::Postgres(c) => sqlx::raw_sql(sql).execute(&mut **c).await.map(drop),
-            Held::Mysql(c) => sqlx::raw_sql(sql).execute(&mut **c).await.map(drop),
+            Held::SqlServer(c) => mssql_command(c, sql).await,
+            other => {
+                let sql = sqlx::AssertSqlSafe(sql.to_owned());
+                match other {
+                    Held::Sqlite(c) => sqlx::raw_sql(sql).execute(&mut **c).await.map(drop),
+                    Held::Postgres(c) => sqlx::raw_sql(sql).execute(&mut **c).await.map(drop),
+                    Held::Mysql(c) => sqlx::raw_sql(sql).execute(&mut **c).await.map(drop),
+                    Held::SqlServer(_) => unreachable!(),
+                }
+                .map_err(db_err)
+            }
        }
-        .map_err(db_err)
    }

    /// Closes the connection instead of returning it to the pool (its statement was
@@ -542,6 +830,9 @@ impl Held {
            Held::Mysql(c) => {
                let _ = c.detach().close().await;
            }
+            Held::SqlServer(mut c) => {
+                c.0.take();
+            }
        }
    }

@@ -589,6 +880,13 @@ impl Held {
                run!(c, Some("SELECT pg_backend_pid()"), |b: String| format!("SELECT pg_cancel_backend({b})"))
            }
            Held::Mysql(c) => run!(c, Some("SELECT CONNECTION_ID()"), |b: String| format!("KILL QUERY {b}")),
+            Held::SqlServer(c) => {
+                // Tiberius has no attention/cancel API; stop reading and discard the connection.
+                tokio::select! {
+                    r = mssql_fetch(c, sql, max_rows) => r?,
+                    () = cancel.cancelled() => return Err(IdeError::cancelled()),
+                }
+            }
        };
        let (columns, rows, affected, has_more, first) = fetched;
        let elapsed_ms = started.elapsed().as_secs_f64() * 1000.0;
@@ -608,6 +906,7 @@ impl Held {
 pub fn begin_statement(driver: DbDriver) -> &'static str {
    match driver {
        DbDriver::Mysql => "START TRANSACTION",
+        DbDriver::SqlServer => "BEGIN TRAN",
        DbDriver::Sqlite | DbDriver::Postgres => "BEGIN",
    }
 }
@@ -624,6 +923,95 @@ mod tests {
    use super::*;
    use crate::source::{DbOptions, DbProperty};

+    #[test]
+    fn discarded_sqlserver_connections_are_broken() {
+        let manager = MssqlConnectionManager(tiberius::Config::new());
+        assert!(manager.has_broken(&mut MssqlConnection(None)));
+    }
+
+    #[tokio::test]
+    async fn sqlserver_connect_reports_io_errors() {
+        let listener = tokio::net::TcpListener::bind("127.0.0.1:0").await.unwrap();
+        let mut config = tiberius::Config::new();
+        config.host("127.0.0.1");
+        config.port(listener.local_addr().unwrap().port());
+        drop(listener);
+        let result = MssqlConnectionManager(config).connect().await;
+        assert!(matches!(result, Err(tiberius::error::Error::Io { .. })));
+    }
+
+    #[test]
+    fn sqlserver_cells_preserve_values_and_nulls() {
+        use std::borrow::Cow;
+        use tiberius::time::{Date, DateTime, DateTime2, DateTimeOffset, SmallDateTime, Time};
+        use tiberius::{ColumnData as C, ColumnType as T, Uuid, numeric::Numeric};
+        let dt = DateTime2::new(Date::new(693_595), Time::new(1234567, 7));
+        let cases = [
+            (C::U8(Some(255)), "255"),
+            (C::I16(Some(-123)), "-123"),
+            (C::I32(Some(-456)), "-456"),
+            (C::I64(Some(i64::MAX)), "9223372036854775807"),
+            (C::F32(Some(1.25)), "1.25"),
+            (C::F64(Some(1.25)), "1.25"),
+            (C::Bit(Some(true)), "true"),
+            (C::String(Some(Cow::Borrowed("hello"))), "hello"),
+            (C::Binary(Some(Cow::Borrowed(&[0, 0xAB, 0xFF]))), "0x00ABFF"),
+            (
+                C::Guid(Some(Uuid::parse_str("ABCDEF01-2345-6789-ABCD-EF0123456789").unwrap())),
+                "abcdef01-2345-6789-abcd-ef0123456789",
+            ),
+            (C::Numeric(Some(Numeric::new_with_scale(-123, 5))), "-0.00123"),
+            (C::Numeric(Some(Numeric::new_with_scale(12300, 4))), "1.2300"),
+            (
+                C::Numeric(Some(Numeric::new_with_scale(10i128.pow(38) - 1, 0))),
+                "99999999999999999999999999999999999999",
+            ),
+            (C::Xml(Some(Cow::Owned(tiberius::xml::XmlData::new("<a/>")))), "<a/>"),
+            (C::Date(Some(Date::new(0))), "0001-01-01"),
+            (C::Date(Some(Date::new(3_652_058))), "9999-12-31"),
+            (C::Time(Some(Time::new(452961234567, 7))), "12:34:56.1234567"),
+            (C::DateTime(Some(DateTime::new(-1, 1))), "1899-12-31 00:00:00.003"),
+            (C::DateTime(Some(DateTime::new(0, 2))), "1900-01-01 00:00:00.007"),
+            (C::SmallDateTime(Some(SmallDateTime::new(0, 754))), "1900-01-01 12:34:00"),
+            (C::DateTime2(Some(dt)), "1900-01-01 00:00:00.1234567"),
+            (C::DateTimeOffset(Some(DateTimeOffset::new(dt, -60))), "1899-12-31 23:00:00.1234567-01:00"),
+            (C::DateTimeOffset(Some(DateTimeOffset::new(dt, 330))), "1900-01-01 05:30:00.1234567+05:30"),
+        ];
+        for (cell, expected) in cases {
+            assert_eq!(tiberius_cell(&cell, T::Null).as_deref(), Some(expected), "{cell:?}");
+        }
+        for cell in [
+            C::U8(None),
+            C::I16(None),
+            C::I32(None),
+            C::I64(None),
+            C::F32(None),
+            C::F64(None),
+            C::Bit(None),
+            C::String(None),
+            C::Guid(None),
+            C::Binary(None),
+            C::Numeric(None),
+            C::Xml(None),
+            C::Date(None),
+            C::Time(None),
+            C::DateTime(None),
+            C::SmallDateTime(None),
+            C::DateTime2(None),
+            C::DateTimeOffset(None),
+        ] {
+            assert_eq!(tiberius_cell(&cell, T::Null), None);
+        }
+        for ty in [T::Money, T::Money4] {
+            for (v, expected) in
+                [(0.0, "0.0000"), (1.2, "1.2000"), (-123.4567, "-123.4567"), (214748.3647, "214748.3647")]
+            {
+                assert_eq!(tiberius_cell(&C::F64(Some(v)), ty).as_deref(), Some(expected));
+            }
+            assert_eq!(tiberius_cell(&C::F64(None), ty), None);
+        }
+    }
+
    fn prop(name: &str, value: &str) -> DbProperty {
        DbProperty { name: name.into(), value: value.into() }
    }
@@ -549,6 +549,7 @@ impl DbManager {
            DbDriver::Sqlite => "SELECT 'SQLite ' || sqlite_version()",
            DbDriver::Postgres => "SELECT version()",
            DbDriver::Mysql => "SELECT CONCAT(@@version_comment, ' ', VERSION())",
+            DbDriver::SqlServer => "SELECT @@VERSION",
        };
        let v = pool.rows(version, 1).await.ok().and_then(|r| r.into_iter().next()?.into_iter().next()?);
        pool.close().await;
@@ -821,6 +822,13 @@ impl DbManager {
                let ddl = cells(pool.rows(&q, 1).await?, 1).into_iter().next();
                ddl.map(|d| format!("{d};\n")).ok_or_else(missing)
            }
+            DbDriver::SqlServer => {
+                let obj = format!("{}.{}", schema, name).replace('\'', "''");
+                let ddl = cells(pool.rows(&format!("SELECT OBJECT_DEFINITION(OBJECT_ID('{}'))", obj), 1).await?, 0)
+                    .into_iter()
+                    .next();
+                ddl.map(|d| format!("{d};\n")).ok_or_else(missing)
+            }
            DbDriver::Postgres => {
                let rel = pool.rows(&sql::postgres_relation(schema, name), 1).await?.into_iter().next();
                let (oid, kind) = match rel.as_deref() {
@@ -36,6 +36,7 @@ pub fn explain_statement(driver: DbDriver, statement: &str) -> String {
        DbDriver::Sqlite => format!("EXPLAIN QUERY PLAN {s}"),
        DbDriver::Postgres => format!("EXPLAIN (FORMAT JSON) {s}"),
        DbDriver::Mysql => format!("EXPLAIN {s}"),
+        DbDriver::SqlServer => format!("SET SHOWPLAN_TEXT ON; {s}"),
    }
 }

@@ -59,6 +60,7 @@ pub fn parse(driver: DbDriver, result: &QueryResult) -> IdeResult<Vec<PlanNode>>
            let names: Vec<&str> = result.columns.iter().map(|c| c.name.as_str()).collect();
            Ok(mysql(&names, &result.rows))
        }
+        DbDriver::SqlServer => Ok(Vec::new()),
    }
 }

@@ -197,6 +199,7 @@ mod tests {
        assert_eq!(explain_statement(DbDriver::Sqlite, "select 1;"), "EXPLAIN QUERY PLAN select 1");
        assert_eq!(explain_statement(DbDriver::Postgres, " select 1 "), "EXPLAIN (FORMAT JSON) select 1");
        assert_eq!(explain_statement(DbDriver::Mysql, "select 1"), "EXPLAIN select 1");
+        assert_eq!(explain_statement(DbDriver::SqlServer, "select 1"), "SET SHOWPLAN_TEXT ON; select 1");
    }

    #[test]
@@ -16,6 +16,8 @@ pub enum DbDriver {
    Postgres,
    /// MySQL and MariaDB.
    Mysql,
+    /// Microsoft SQL Server.
+    SqlServer,
 }

 impl DbDriver {
@@ -24,6 +26,7 @@ impl DbDriver {
            DbDriver::Sqlite => None,
            DbDriver::Postgres => Some(5432),
            DbDriver::Mysql => Some(3306),
+            DbDriver::SqlServer => Some(1433),
        }
    }
 }
@@ -248,6 +251,7 @@ pub fn scheme_driver(scheme: &str) -> Option<DbDriver> {
        "postgres" | "postgresql" | "pgsql" | "redshift" | "cockroachdb" | "cockroach" | "yugabytedb"
        | "timescaledb" | "greenplum" => Some(DbDriver::Postgres),
        "mysql" | "mariadb" | "tidb" | "singlestore" | "memsql" | "oceanbase" => Some(DbDriver::Mysql),
+        "sqlserver" | "mssql" | "mssqlserver" => Some(DbDriver::SqlServer),
        "sqlite" | "sqlite3" => Some(DbDriver::Sqlite),
        _ => None,
    }
@@ -472,6 +476,14 @@ mod tests {
        assert_eq!(load(tmp.path()).unwrap(), vec![s]);
    }

+    #[test]
+    fn sqlserver_defaults() {
+        assert_eq!(DbDriver::SqlServer.default_port(), Some(1433));
+        assert_eq!(scheme_driver("sqlserver"), Some(DbDriver::SqlServer));
+        assert_eq!(scheme_driver("mssql"), Some(DbDriver::SqlServer));
+        assert_eq!(scheme_driver("mssqlserver"), Some(DbDriver::SqlServer));
+    }
+
    #[test]
    fn parses_urls() {
        let u = parse_url("jdbc:postgresql://ann:s%[email protected]:5433/shop?sslmode=require&search_path=app").unwrap();
@@ -8,6 +8,7 @@ use specta::Type;
 pub fn quote_ident(driver: DbDriver, name: &str) -> String {
    match driver {
        DbDriver::Mysql => format!("`{}`", name.replace('`', "``")),
+        DbDriver::SqlServer => format!("[{}]", name.replace(']', "]]")),
        _ => format!("\"{}\"", name.replace('"', "\"\"")),
    }
 }
@@ -52,6 +53,7 @@ pub fn schemas(driver: DbDriver, system: bool) -> &'static str {
             WHERE schema_name NOT LIKE 'pg\\_toast%' AND schema_name NOT LIKE 'pg\\_temp%' ORDER BY 1"
        }
        DbDriver::Mysql if system => "SELECT schema_name FROM information_schema.schemata ORDER BY 1",
+        DbDriver::SqlServer if system => "SELECT schema_name FROM information_schema.schemata ORDER BY 1",
        DbDriver::Postgres => {
            "SELECT schema_name FROM information_schema.schemata \
             WHERE schema_name NOT IN ('pg_catalog', 'information_schema') \
@@ -61,6 +63,10 @@ pub fn schemas(driver: DbDriver, system: bool) -> &'static str {
            "SELECT schema_name FROM information_schema.schemata \
             WHERE schema_name NOT IN ('information_schema', 'mysql', 'performance_schema', 'sys') ORDER BY 1"
        }
+        DbDriver::SqlServer => {
+            "SELECT schema_name FROM information_schema.schemata \
+             WHERE schema_name NOT IN ('sys', 'information_schema', 'guest') ORDER BY 1"
+        }
    }
 }

@@ -83,6 +89,11 @@ pub fn tables(driver: DbDriver, schema: &str) -> String {
             FROM information_schema.tables WHERE table_schema = {} ORDER BY 1",
            quote_literal(driver, schema)
        ),
+        DbDriver::SqlServer => format!(
+            "SELECT table_name, CASE WHEN table_type LIKE '%VIEW%' THEN 'view' ELSE 'table' END \
+             FROM information_schema.tables WHERE table_schema = {} ORDER BY 1",
+            quote_literal(driver, schema)
+        ),
    }
 }

@@ -110,6 +121,16 @@ pub fn columns(driver: DbDriver, schema: &str, table: &str) -> String {
             FROM information_schema.columns WHERE table_schema = {s} AND table_name = {t} \
             ORDER BY ordinal_position"
        ),
+        DbDriver::SqlServer => format!(
+            "SELECT column_name, data_type, is_nullable, column_default, \
+             CASE WHEN EXISTS (SELECT 1 FROM information_schema.table_constraints tc \
+               JOIN information_schema.key_column_usage k ON k.constraint_name = tc.constraint_name \
+               AND k.table_schema = tc.table_schema AND k.table_name = tc.table_name \
+               WHERE tc.constraint_type = 'PRIMARY KEY' AND tc.table_schema = {s} \
+               AND tc.table_name = {t} AND k.column_name = c.column_name) THEN 1 ELSE 0 END \
+             FROM information_schema.columns c WHERE c.table_schema = {s} AND c.table_name = {t} \
+             ORDER BY c.ordinal_position"
+        ),
    }
 }

@@ -134,6 +155,13 @@ pub fn indexes(driver: DbDriver, schema: &str, table: &str) -> String {
             FROM information_schema.statistics WHERE table_schema = {s} AND table_name = {t} \
             ORDER BY index_name, seq_in_index"
        ),
+        DbDriver::SqlServer => format!(
+            "SELECT i.name, CASE WHEN i.is_unique = 1 THEN 1 ELSE 0 END, c.name \
+             FROM sys.indexes i JOIN sys.index_columns ic ON ic.object_id = i.object_id AND ic.index_id = i.index_id \
+             JOIN sys.columns c ON c.object_id = ic.object_id AND c.column_id = ic.column_id \
+             WHERE OBJECT_SCHEMA_NAME(i.object_id) = {s} AND OBJECT_NAME(i.object_id) = {t} AND i.name IS NOT NULL \
+             ORDER BY i.name, ic.key_ordinal"
+        ),
    }
 }

@@ -171,6 +199,20 @@ pub fn completion_columns(driver: DbDriver) -> &'static str {
             WHERE c.table_schema NOT IN ('information_schema', 'mysql', 'performance_schema', 'sys') \
             ORDER BY c.table_schema, c.table_name, c.ordinal_position LIMIT 50000"
        }
+        DbDriver::SqlServer => {
+            "SELECT c.table_schema, c.table_name, CASE WHEN t.table_type LIKE '%VIEW%' THEN 'view' ELSE 'table' END, \
+             c.column_name, c.data_type, c.is_nullable, \
+             CASE WHEN EXISTS (SELECT 1 FROM information_schema.table_constraints tc \
+               JOIN information_schema.key_column_usage k ON k.constraint_name = tc.constraint_name \
+               AND k.table_schema = tc.table_schema AND k.table_name = tc.table_name \
+               WHERE tc.constraint_type = 'PRIMARY KEY' AND tc.table_schema = c.table_schema \
+               AND tc.table_name = c.table_name AND k.column_name = c.column_name) THEN 1 ELSE 0 END, \
+             CASE WHEN c.column_default IS NOT NULL THEN 1 ELSE 0 END \
+             FROM information_schema.columns c JOIN information_schema.tables t \
+             ON t.table_schema = c.table_schema AND t.table_name = c.table_name \
+             WHERE c.table_schema NOT IN ('sys', 'information_schema') \
+             ORDER BY c.table_schema, c.table_name, c.ordinal_position"
+        }
    }
 }

@@ -202,6 +244,13 @@ pub fn foreign_keys(driver: DbDriver) -> &'static str {
             AND table_schema NOT IN ('information_schema', 'mysql', 'performance_schema', 'sys') \
             ORDER BY table_schema, table_name, constraint_name, ordinal_position LIMIT 20000"
        }
+        DbDriver::SqlServer => {
+            "SELECT table_schema, table_name, constraint_name, column_name, \
+             referenced_table_schema, referenced_table_name, referenced_column_name \
+             FROM information_schema.key_column_usage WHERE referenced_table_name IS NOT NULL \
+             AND table_schema NOT IN ('sys', 'information_schema') \
+             ORDER BY table_schema, table_name, constraint_name, ordinal_position"
+        }
    }
 }

@@ -218,6 +267,9 @@ pub fn table_foreign_keys(driver: DbDriver, schema: &str, table: &str) -> String
        DbDriver::Mysql => format!(
            "SELECT table_schema, table_name, constraint_name, column_name,              referenced_table_schema, referenced_table_name, referenced_column_name              FROM information_schema.key_column_usage WHERE referenced_table_name IS NOT NULL              AND table_schema = {s} AND table_name = {t} ORDER BY constraint_name, ordinal_position"
        ),
+        DbDriver::SqlServer => format!(
+            "SELECT table_schema, table_name, constraint_name, column_name,              referenced_table_schema, referenced_table_name, referenced_column_name              FROM information_schema.key_column_usage WHERE referenced_table_name IS NOT NULL              AND table_schema = {s} AND table_name = {t} ORDER BY constraint_name, ordinal_position"
+        ),
    }
 }

@@ -227,6 +279,7 @@ pub fn current_schema(driver: DbDriver) -> Option<&'static str> {
        DbDriver::Sqlite => None,
        DbDriver::Postgres => Some("SELECT current_schema()"),
        DbDriver::Mysql => Some("SELECT DATABASE()"),
+        DbDriver::SqlServer => Some("SELECT DB_NAME()"),
    }
 }

@@ -250,8 +303,14 @@ pub fn table_page(
 ) -> String {
    let mut sql = format!("SELECT * FROM {}", qualified(driver, schema, table));
    if let Some(f) = filter.map(str::trim).filter(|f| !f.is_empty()) {
-        let f = f.strip_prefix("WHERE ").or_else(|| f.strip_prefix("where ")).unwrap_or(f);
-        sql.push_str(&format!(" WHERE {f}"));
+        let mut f = f.strip_prefix("WHERE ").or_else(|| f.strip_prefix("where ")).unwrap_or(f);
+        if let Some(i) = f.find(';') {
+            f = &f[..i];
+        }
+        f = f.trim();
+        if !f.is_empty() {
+            sql.push_str(&format!(" WHERE {f}"));
+        }
    }
    if !sort.is_empty() {
        let keys: Vec<String> = sort
@@ -260,7 +319,14 @@ pub fn table_page(
            .collect();
        sql.push_str(&format!(" ORDER BY {}", keys.join(", ")));
    }
-    sql.push_str(&format!(" LIMIT {} OFFSET {offset}", limit + 1));
+    if driver == DbDriver::SqlServer {
+        if sort.is_empty() {
+            sql.push_str(" ORDER BY (SELECT 1)");
+        }
+        sql.push_str(&format!(" OFFSET {offset} ROWS FETCH NEXT {} ROWS ONLY", limit + 1));
+    } else {
+        sql.push_str(&format!(" LIMIT {} OFFSET {offset}", limit + 1));
+    }
    sql
 }

@@ -400,6 +466,10 @@ pub fn triggers(driver: DbDriver, schema: &str, table: &str) -> String {
            "SELECT trigger_name, lower(action_timing), lower(event_manipulation) FROM information_schema.triggers \
             WHERE event_object_schema = {s} AND event_object_table = {t} ORDER BY 1"
        ),
+        DbDriver::SqlServer => format!(
+            "SELECT t.name, lower(te.type_desc), '' FROM sys.triggers t \
+             WHERE OBJECT_SCHEMA_NAME(t.parent_id) = {s} AND OBJECT_NAME(t.parent_id) = {t} ORDER BY 1"
+        ),
    }
 }

@@ -438,6 +508,10 @@ pub fn routines(driver: DbDriver, schema: &str) -> Option<String> {
              AND p.specific_name = r.specific_name AND p.ordinal_position > 0), r.dtd_identifier \
             FROM information_schema.routines r WHERE r.routine_schema = {s} ORDER BY 1"
        )),
+        DbDriver::SqlServer => Some(format!(
+            "SELECT r.routine_name, lower(r.routine_type), '', r.data_type \
+             FROM information_schema.routines r WHERE r.routine_schema = {s} ORDER BY 1"
+        )),
    }
 }

@@ -559,6 +633,10 @@ mod tests {
            "SELECT * FROM \"public\".\"users\" WHERE age > 3 ORDER BY \"id\" DESC LIMIT 51 OFFSET 100"
        );
        assert_eq!(table_page(DbDriver::Mysql, "", "t", Some("  "), &[], 0, 10), "SELECT * FROM `t` LIMIT 11 OFFSET 0");
+        assert_eq!(
+            table_page(DbDriver::SqlServer, "dbo", "users", Some("id = 1;"), &[], 0, 500),
+            "SELECT * FROM [dbo].[users] WHERE id = 1 ORDER BY (SELECT 1) OFFSET 0 ROWS FETCH NEXT 501 ROWS ONLY"
+        );
    }

    #[test]
@@ -586,6 +664,30 @@ mod tests {
        assert!(edit_statement(DbDriver::Postgres, "s", "t", &DbRowEdit::Delete { key: vec![] }).is_err());
    }

+    #[test]
+    fn sqlserver_quoting_and_schema() {
+        assert_eq!(quote_ident(DbDriver::SqlServer, "a]b"), "[a]]b]");
+        assert_eq!(qualified(DbDriver::SqlServer, "dbo", "t"), "[dbo].[t]");
+        assert_eq!(qualified(DbDriver::SqlServer, "", "t"), "[t]");
+        assert_eq!(current_schema(DbDriver::SqlServer), Some("SELECT DB_NAME()"));
+        assert_eq!(crate::conn::begin_statement(DbDriver::SqlServer), "BEGIN TRAN");
+        assert_eq!(
+            schemas(DbDriver::SqlServer, true),
+            "SELECT schema_name FROM information_schema.schemata ORDER BY 1"
+        );
+        assert!(schemas(DbDriver::SqlServer, false).contains("NOT IN ('sys', 'information_schema', 'guest')"));
+    }
+
+    #[test]
+    fn sqlserver_introspection_queries() {
+        assert!(tables(DbDriver::SqlServer, "dbo").contains("information_schema.tables"));
+        assert!(columns(DbDriver::SqlServer, "dbo", "t").contains("information_schema.columns"));
+        assert!(indexes(DbDriver::SqlServer, "dbo", "t").contains("sys.indexes"));
+        assert!(foreign_keys(DbDriver::SqlServer).contains("referenced_table_name IS NOT NULL"));
+        assert!(table_foreign_keys(DbDriver::SqlServer, "dbo", "t").contains("table_schema = 'dbo'"));
+        assert!(completion_columns(DbDriver::SqlServer).contains("information_schema.columns"));
+    }
+
    #[test]
    fn sqlite_trigger_events() {
        let ev = sqlite_trigger_event;
@@ -0,0 +1,97 @@
+//! Live SQL Server checks, skipped unless OPENIDEA_TEST_SQLSERVER=host:port:user:password
+//! names a throwaway server.
+
+use ide_core::CancellationToken;
+use ide_db::{DataSource, DbDriver, DbSslMode, Held, Pool};
+use std::time::Duration;
+
+#[tokio::test]
+async fn sqlserver_values_paging_transactions_and_cancellation() {
+    let Ok(server) = std::env::var("OPENIDEA_TEST_SQLSERVER") else { return };
+    let mut parts = server.splitn(4, ':');
+    let source = DataSource {
+        driver: DbDriver::SqlServer,
+        host: parts.next().unwrap().into(),
+        port: Some(parts.next().unwrap().parse().unwrap()),
+        user: parts.next().unwrap().into(),
+        database: "tempdb".into(),
+        ssl: DbSslMode::Disable,
+        ..Default::default()
+    };
+    let pool = Pool::connect(&source, parts.next(), None).await.unwrap();
+    let cancel = CancellationToken::new();
+    let mut held = Held::acquire(&pool).await.unwrap();
+    let table = format!("tempdb.dbo.oi_pr276_values_{}", std::process::id());
+    held.command(&format!("CREATE TABLE {table} (id int PRIMARY KEY, d decimal(38, 7), dt datetime2(7), guid uniqueidentifier, m money, tiny tinyint, x xml)")).await.unwrap();
+    held.command(&format!("INSERT INTO {table} VALUES (1, 12345678901234567890.1234567, '2024-02-29T12:34:56.1234567', 'abcdef01-2345-6789-abcd-ef0123456789', 12.3400, 255, '<a/>'), (2, NULL, NULL, NULL, NULL, NULL, NULL)")).await.unwrap();
+    let r = held.execute(&pool, &format!("SELECT * FROM {table} ORDER BY id"), 1, &cancel).await.unwrap();
+    assert!(r.has_more);
+    assert_eq!(
+        r.rows[0],
+        [
+            "1",
+            "12345678901234567890.1234567",
+            "2024-02-29 12:34:56.1234567",
+            "abcdef01-2345-6789-abcd-ef0123456789",
+            "12.3400",
+            "255",
+            "<a/>"
+        ]
+        .map(|s| Some(s.to_owned()))
+    );
+    let r = held.execute(&pool, &format!("SELECT * FROM {table} WHERE id = 2"), 5, &cancel).await.unwrap();
+    assert!(!r.has_more);
+    assert!(r.rows[0][1..].iter().all(Option::is_none));
+    let r = held.execute(&pool, &format!("SELECT * FROM {table} WHERE id = 3"), 5, &cancel).await.unwrap();
+    assert_eq!(r.columns.len(), 7);
+    assert!(r.rows.is_empty());
+    let r = held.execute(&pool,
+        "SELECT CAST('2024-02-29T00:15:00.1234567+05:30' AS datetimeoffset(7)), CAST('2024-02-29' AS date), CAST('12:34:56.1234567' AS time(7)), CAST('2024-02-29T12:34:56.007' AS datetime), CAST('2024-02-29T12:34:00' AS smalldatetime), CAST(-12.3400 AS smallmoney)",
+        1, &cancel).await.unwrap();
+    assert_eq!(
+        r.rows[0],
+        [
+            "2024-02-29 00:15:00.1234567+05:30",
+            "2024-02-29",
+            "12:34:56.1234567",
+            "2024-02-29 12:34:56.007",
+            "2024-02-29 12:34:00",
+            "-12.3400"
+        ]
+        .map(|s| Some(s.to_owned()))
+    );
+    held.command(&format!("DROP TABLE {table}")).await.unwrap();
+    drop(held);
+
+    // A unique permanent table lets transaction calls acquire any pooled connection.
+    let table = format!("tempdb.dbo.oi_pr276_{}", std::process::id());
+    pool.execute(&format!("CREATE TABLE {table} (id int PRIMARY KEY, v int)"), 1, &cancel).await.unwrap();
+    pool.transaction(&[(format!("INSERT INTO {table} VALUES (1, 10)"), true)]).await.unwrap();
+    for failing in [format!("INSERT INTO {table} VALUES (1, 20)"), format!("UPDATE {table} SET v = 30 WHERE id = 999")]
+    {
+        assert!(
+            pool.transaction(&[(format!("UPDATE {table} SET v = 99 WHERE id = 1"), true), (failing, true)])
+                .await
+                .is_err()
+        );
+        assert_eq!(pool.rows(&format!("SELECT v FROM {table}"), 1).await.unwrap()[0][0].as_deref(), Some("10"));
+        assert_eq!(pool.rows("SELECT @@TRANCOUNT", 1).await.unwrap()[0][0].as_deref(), Some("0"));
+    }
+    assert_eq!(pool.transaction(&[(format!("UPDATE {table} SET v = 11 WHERE id = 1"), true)]).await.unwrap(), 1);
+    pool.execute(&format!("DROP TABLE {table}"), 1, &cancel).await.unwrap();
+
+    let cancel = CancellationToken::new();
+    let stop = cancel.clone();
+    let task = tokio::spawn(async move {
+        tokio::time::sleep(Duration::from_millis(100)).await;
+        stop.cancel();
+    });
+    assert!(
+        tokio::time::timeout(Duration::from_secs(2), pool.execute("WAITFOR DELAY '00:00:10'; SELECT 1", 1, &cancel))
+            .await
+            .unwrap()
+            .is_err()
+    );
+    task.await.unwrap();
+    assert_eq!(pool.rows("SELECT 1", 1).await.unwrap()[0][0].as_deref(), Some("1"));
+}
@@ -54,7 +54,7 @@ fn read_all(mut pipe: impl Read + Send + 'static) -> std::thread::JoinHandle<Str
    std::thread::spawn(move || {
        let mut buf = Vec::new();
        let _ = pipe.read_to_end(&mut buf);
-        String::from_utf8_lossy(&buf).into_owned()
+        ide_core::output_encoding::decode_tool_output(&buf)
    })
 }

@@ -115,7 +115,7 @@ fn spawn_reader(mut pipe: impl Read + Send + 'static, tx: mpsc::Sender<Event>, s
        let mut pending: Vec<u8> = Vec::new();
        let flush = |pending: &mut Vec<u8>| {
            if !pending.is_empty() {
-                let line = String::from_utf8_lossy(pending).trim_end().to_string();
+                let line = ide_core::output_encoding::decode_tool_output(pending).trim_end().to_string();
                pending.clear();
                let _ = tx.send(Event::Line(stream, line));
            }
@@ -7,10 +7,11 @@ license.workspace = true

 [dependencies]
 serde.workspace = true
+serde_json.workspace = true
 specta.workspace = true

 [target.'cfg(target_os = "macos")'.dependencies]
-objc2-core-foundation = { version = "0.3", default-features = false, features = ["std", "CFArray", "CFDictionary", "CFNumber", "CFString"] }
+objc2-core-foundation = { version = "0.3", default-features = false, features = ["std", "CFArray", "CFDictionary", "CFNumber", "CFString", "CFURL"] }
 objc2-core-text = { version = "0.3", default-features = false, features = ["std", "CTFontCollection", "CTFontDescriptor", "CTFontTraits"] }

 [target.'cfg(windows)'.dependencies]
@@ -1,16 +1,16 @@
 //! The font families installed on this machine, for the font pickers in
 //! Settings (editor, typography fallback, terminal, UI font).
 //!
-//! Each platform asks the font system the WebView itself resolves CSS
-//! `font-family` names against, so every listed name renders: CoreText on
+//! Each platform asks the native font system for installed families: CoreText on
 //! macOS, DirectWrite on Windows, fontconfig (`fc-list`) on Linux and the BSDs.
-//! The list is read once per run and cached; the first read can take a few
-//! hundred milliseconds, so callers run it off the UI and command threads.
+//! The list is read on first use and cached until explicitly refreshed; the
+//! query can take a few hundred milliseconds, so callers run it off the UI and
+//! command threads.

 use serde::{Deserialize, Serialize};
 use specta::Type;
 use std::collections::BTreeMap;
-use std::sync::OnceLock;
+use std::sync::{Arc, Mutex};

 /// One installed family. `monospaced` is the font system's own flag (fixed
 /// pitch; on Linux also fontconfig's dual-width CJK monospace).
@@ -21,10 +21,23 @@ pub struct FontFamily {
    pub monospaced: bool,
 }

-/// The installed families, sorted case-insensitively, read on first use.
-pub fn families() -> &'static [FontFamily] {
-    static CACHE: OnceLock<Vec<FontFamily>> = OnceLock::new();
-    CACHE.get_or_init(|| normalize(imp::list()))
+type Cache = Mutex<Option<Arc<[FontFamily]>>>;
+
+/// The installed families, sorted case-insensitively, read on first use and
+/// re-queried when `refresh` is true.
+pub fn families(refresh: bool) -> Arc<[FontFamily]> {
+    static CACHE: Cache = Mutex::new(None);
+    cached(&CACHE, refresh, imp::list)
+}
+
+fn cached(cache: &Cache, refresh: bool, list: impl FnOnce(bool) -> Vec<(String, bool)>) -> Arc<[FontFamily]> {
+    let mut guard = cache.lock().unwrap_or_else(|e| e.into_inner());
+    if !refresh && let Some(families) = guard.as_ref() {
+        return Arc::clone(families);
+    }
+    let families: Arc<[FontFamily]> = normalize(list(refresh)).into();
+    *guard = Some(Arc::clone(&families));
+    families
 }

 /// Merges the per-face records a font system reports into one entry per
@@ -70,16 +83,166 @@ pub fn parse_fc_list(output: &str) -> Vec<(String, bool)> {
        .collect()
 }

+/// Binary font bundle: little-endian u32 JSON-header length, a face metadata
+/// array, then raw font bytes. Paths never cross IPC; only CoreText-enumerated
+/// files under user font directories can be read, selected by family name.
+/// Includes only the nearest regular/bold faces and their optional italics.
+pub fn user_font_data(family: &str) -> std::io::Result<Vec<u8>> {
+    #[cfg(target_os = "macos")]
+    {
+        let entries = imp::user_faces();
+        bundle_family(family, &entries)
+    }
+    #[cfg(not(target_os = "macos"))]
+    {
+        let _ = family;
+        Err(std::io::Error::new(std::io::ErrorKind::Unsupported, "User font loading is macOS only"))
+    }
+}
+
+#[cfg(any(target_os = "macos", test))]
+#[derive(Debug)]
+struct UserFace {
+    family: String,
+    path: std::path::PathBuf,
+    weight: u16,
+    italic: bool,
+}
+
+#[cfg(any(target_os = "macos", test))]
+fn user_font_path(path: &std::path::Path, roots: &[std::path::PathBuf]) -> Option<std::path::PathBuf> {
+    let path = path.canonicalize().ok()?;
+    roots.iter().any(|root| path.starts_with(root)).then_some(path)
+}
+
+#[cfg(any(target_os = "macos", test))]
+fn family_faces<'a>(family: &str, entries: &'a [UserFace]) -> Vec<&'a UserFace> {
+    let mut selected: Vec<&UserFace> = Vec::new();
+    for italic in [false, true] {
+        for weight in [400u16, 700] {
+            let closest = entries
+                .iter()
+                .filter(|e| e.family.eq_ignore_ascii_case(family.trim()) && e.italic == italic)
+                .min_by_key(|e| (e.weight.abs_diff(weight), e.weight, &e.path));
+            if let Some(face) = closest
+                && !selected.iter().any(|f| std::ptr::eq(*f, face))
+            {
+                selected.push(face);
+            }
+        }
+    }
+    selected
+}
+
+#[cfg(any(target_os = "macos", test))]
+fn bundle_family(family: &str, entries: &[UserFace]) -> std::io::Result<Vec<u8>> {
+    #[derive(Serialize)]
+    struct Face {
+        weight: u16,
+        style: &'static str,
+        offset: usize,
+        length: usize,
+    }
+    let mut faces = Vec::new();
+    let mut data = Vec::new();
+    let mut files = BTreeMap::new();
+    // Bound large CJK families to regular/bold and their nearest italic faces.
+    for entry in family_faces(family, entries) {
+        // Reject a file replaced by a symlink after enumeration.
+        if entry.path.canonicalize()? != entry.path {
+            return Err(std::io::Error::new(std::io::ErrorKind::PermissionDenied, "Font file changed"));
+        }
+        let (offset, length) = if let Some(range) = files.get(&entry.path) {
+            *range
+        } else {
+            let bytes = std::fs::read(&entry.path)?;
+            let range = (data.len(), bytes.len());
+            data.extend(bytes);
+            files.insert(entry.path.clone(), range);
+            range
+        };
+        faces.push(Face {
+            weight: entry.weight,
+            style: if entry.italic { "italic" } else { "normal" },
+            offset,
+            length,
+        });
+    }
+    if faces.is_empty() {
+        return Err(std::io::Error::new(std::io::ErrorKind::NotFound, "No installed user font family"));
+    }
+    let header = serde_json::to_vec(&faces)?;
+    let mut out = (header.len() as u32).to_le_bytes().to_vec();
+    out.extend(header);
+    out.extend(data);
+    Ok(out)
+}
+
 #[cfg(target_os = "macos")]
 mod imp {
-    use objc2_core_foundation::{CFArray, CFDictionary, CFNumber, CFString, CFType};
+    use objc2_core_foundation::{CFArray, CFDictionary, CFNumber, CFString, CFType, CFURL};
    use objc2_core_text::{
        CTFontCollection, CTFontDescriptor, CTFontSymbolicTraits, kCTFontFamilyNameAttribute, kCTFontSymbolicTrait,
-        kCTFontTraitsAttribute,
+        kCTFontTraitsAttribute, kCTFontURLAttribute, kCTFontWeightTrait,
    };

+    pub(crate) fn user_faces() -> Vec<super::UserFace> {
+        let mut roots = vec![std::path::PathBuf::from("/Library/Fonts")];
+        if let Some(home) = std::env::var_os("HOME") {
+            roots.push(std::path::PathBuf::from(home).join("Library/Fonts"));
+        }
+        let roots: Vec<_> = roots.into_iter().filter_map(|r| r.canonicalize().ok()).collect();
+        // SAFETY: CoreText descriptors carry documented CFString, CFURL and trait dictionary values.
+        unsafe {
+            let collection = CTFontCollection::from_available_fonts(None);
+            let Some(descriptors) = collection.matching_font_descriptors() else { return Vec::new() };
+            let mut seen = std::collections::BTreeSet::new();
+            descriptors
+                .cast_unchecked::<CTFontDescriptor>()
+                .iter()
+                .filter_map(|d| {
+                    let family = d.attribute(kCTFontFamilyNameAttribute)?.downcast::<CFString>().ok()?.to_string();
+                    let path = d.attribute(kCTFontURLAttribute)?.downcast::<CFURL>().ok()?.to_file_path()?;
+                    let path = super::user_font_path(&path, &roots)?;
+                    let traits = d.attribute(kCTFontTraitsAttribute)?.downcast::<CFDictionary>().ok()?;
+                    let traits = traits.cast_unchecked::<CFString, CFType>();
+                    let symbolic = traits
+                        .get(kCTFontSymbolicTrait)
+                        .and_then(|n| n.downcast::<CFNumber>().ok())
+                        .and_then(|n| n.as_i64())
+                        .unwrap_or(0) as u32;
+                    let weight = traits
+                        .get(kCTFontWeightTrait)
+                        .and_then(|n| n.downcast::<CFNumber>().ok())
+                        .and_then(|n| n.as_f64())
+                        .unwrap_or(0.0);
+                    // CoreText's normalized weight values corresponding to CSS's nine standard weights.
+                    let weight = [
+                        (-0.8, 100),
+                        (-0.6, 200),
+                        (-0.4, 300),
+                        (0.0, 400),
+                        (0.23, 500),
+                        (0.3, 600),
+                        (0.4, 700),
+                        (0.56, 800),
+                        (0.62, 900),
+                    ]
+                    .into_iter()
+                    .min_by(|(a, _), (b, _)| (weight - a).abs().total_cmp(&(weight - b).abs()))?
+                    .1;
+                    let italic = symbolic & CTFontSymbolicTraits::TraitItalic.0 != 0;
+                    if !seen.insert((family.clone(), path.clone(), weight, italic)) {
+                        return None;
+                    }
+                    Some(super::UserFace { family, path, weight, italic })
+                })
+                .collect()
+        }
+    }
+
    /// Every face CoreText makes available to this process, as (family, fixed pitch).
-    pub(crate) fn list() -> Vec<(String, bool)> {
+    pub(crate) fn list(_refresh: bool) -> Vec<(String, bool)> {
        // SAFETY: CoreText's documented types: the matching descriptors array
        // holds CTFontDescriptors and the traits dictionary maps CFString keys.
        unsafe {
@@ -116,15 +279,15 @@ mod imp {

    /// The system font collection's families, named in English when the
    /// family has an English name (what CSS matches), else its first name.
-    pub(crate) fn list() -> Vec<(String, bool)> {
+    pub(crate) fn list(refresh: bool) -> Vec<(String, bool)> {
        // SAFETY: plain DirectWrite COM calls on interfaces we own.
-        unsafe { read() }.unwrap_or_default()
+        unsafe { read(refresh) }.unwrap_or_default()
    }

-    unsafe fn read() -> windows::core::Result<Vec<(String, bool)>> {
+    unsafe fn read(refresh: bool) -> windows::core::Result<Vec<(String, bool)>> {
        let factory: IDWriteFactory = unsafe { DWriteCreateFactory(DWRITE_FACTORY_TYPE_SHARED) }?;
        let mut collection = None;
-        unsafe { factory.GetSystemFontCollection(&mut collection, false) }?;
+        unsafe { factory.GetSystemFontCollection(&mut collection, refresh) }?;
        let Some(collection) = collection else {
            return Ok(Vec::new());
        };
@@ -171,7 +334,7 @@ mod imp {

    /// fontconfig's view, which WebKitGTK resolves names with. Empty when
    /// `fc-list` isn't installed.
-    pub(crate) fn list() -> Vec<(String, bool)> {
+    pub(crate) fn list(_refresh: bool) -> Vec<(String, bool)> {
        Command::new("fc-list")
            .args(["-f", "%{family[0]}\t%{spacing}\n"])
            .stdin(Stdio::null())
@@ -186,7 +349,7 @@ mod imp {

 #[cfg(not(any(unix, windows)))]
 mod imp {
-    pub(crate) fn list() -> Vec<(String, bool)> {
+    pub(crate) fn list(_refresh: bool) -> Vec<(String, bool)> {
        Vec::new()
    }
 }
@@ -194,6 +357,93 @@ mod imp {
 #[cfg(test)]
 mod tests {
    use super::*;
+    use std::sync::atomic::{AtomicUsize, Ordering};
+
+    #[test]
+    fn selects_only_regular_bold_and_matching_italics_from_dense_families() {
+        let entries: Vec<_> = [false, true]
+            .into_iter()
+            .flat_map(|italic| {
+                (100..=900).step_by(100).map(move |weight| UserFace {
+                    family: "CJK".into(),
+                    path: format!("{weight}-{italic}.ttf").into(),
+                    weight,
+                    italic,
+                })
+            })
+            .collect();
+        let selected = family_faces(" cjk ", &entries);
+        assert_eq!(
+            selected.iter().map(|f| (f.weight, f.italic)).collect::<Vec<_>>(),
+            [(400, false), (700, false), (400, true), (700, true),]
+        );
+        assert!(family_faces("unknown", &entries).is_empty());
+    }
+
+    #[test]
+    fn selects_nearest_available_weights_once_with_optional_italics() {
+        let entries: Vec<_> = [(300, false), (500, false), (800, false), (500, true)]
+            .into_iter()
+            .map(|(weight, italic)| UserFace {
+                family: "Sparse".into(),
+                path: format!("{weight}-{italic}.ttf").into(),
+                weight,
+                italic,
+            })
+            .collect();
+        let selected = family_faces("Sparse", &entries);
+        assert_eq!(
+            selected.iter().map(|f| (f.weight, f.italic)).collect::<Vec<_>>(),
+            [(300, false), (800, false), (500, true),]
+        );
+        assert_eq!(family_faces("Sparse", &entries[..1]).len(), 1);
+    }
+
+    #[test]
+    fn bundle_only_reads_enumerated_family_faces() {
+        let root = std::env::current_dir().unwrap().join(format!("../../.font-bundle-test-{}", std::process::id()));
+        std::fs::create_dir_all(&root).unwrap();
+        let root = root.canonicalize().unwrap();
+        let regular = root.join("regular.ttf");
+        let bold = root.join("bold.ttf");
+        std::fs::write(&regular, [1, 2, 3]).unwrap();
+        std::fs::write(&bold, [4, 5]).unwrap();
+        let entries = [
+            UserFace { family: "Test Nerd Font".into(), path: regular.clone(), weight: 400, italic: false },
+            UserFace { family: "Test Nerd Font".into(), path: bold, weight: 700, italic: false },
+            // A non-selected face is never opened, even if its file has disappeared.
+            UserFace { family: "Test Nerd Font".into(), path: root.join("thin.ttf"), weight: 100, italic: false },
+        ];
+        let result = bundle_family("test nerd font", &entries).unwrap();
+        let len = u32::from_le_bytes(result[..4].try_into().unwrap()) as usize;
+        let faces: serde_json::Value = serde_json::from_slice(&result[4..4 + len]).unwrap();
+        assert_eq!(faces[0]["weight"], 400);
+        assert_eq!(faces[1]["weight"], 700);
+        assert_eq!(faces.as_array().unwrap().len(), 2);
+        assert_eq!(&result[4 + len..], &[1, 2, 3, 4, 5]);
+        // Existing files are not inputs: neither paths nor unenumerated families grant access.
+        assert!(bundle_family(regular.to_str().unwrap(), &entries).is_err());
+        assert!(bundle_family("Unenumerated", &entries).is_err());
+        assert!(user_font_path(&regular, &[]).is_none());
+        assert!(user_font_path(&regular, std::slice::from_ref(&root)).is_some());
+        // Multiple selected descriptors in a collection still transfer the file only once.
+        let shared = [
+            UserFace { family: "Collection".into(), path: regular.clone(), weight: 400, italic: false },
+            UserFace { family: "Collection".into(), path: regular, weight: 700, italic: false },
+        ];
+        let result = bundle_family("Collection", &shared).unwrap();
+        let len = u32::from_le_bytes(result[..4].try_into().unwrap()) as usize;
+        let faces: serde_json::Value = serde_json::from_slice(&result[4..4 + len]).unwrap();
+        assert_eq!(faces[0]["offset"], faces[1]["offset"]);
+        assert_eq!(&result[4 + len..], &[1, 2, 3]);
+        #[cfg(unix)]
+        {
+            let link = root.join("outside.ttf");
+            std::os::unix::fs::symlink(std::env::current_exe().unwrap(), &link).unwrap();
+            assert!(user_font_path(&link, std::slice::from_ref(&root)).is_none());
+        }
+        std::fs::remove_dir_all(root).unwrap();
+    }

    fn fam(name: &str, monospaced: bool) -> FontFamily {
        FontFamily { name: name.into(), monospaced }
@@ -243,12 +493,38 @@ mod tests {
        );
    }

+    #[test]
+    fn caches_until_refresh_requested() {
+        let cache = Mutex::new(None);
+        let calls = AtomicUsize::new(0);
+        let lister = |refresh: bool| {
+            let n = calls.fetch_add(1, Ordering::SeqCst);
+            vec![(format!("Font {n} (refresh={refresh})"), n.is_multiple_of(2))]
+        };
+
+        let first = cached(&cache, false, lister);
+        assert_eq!(&*first, &[fam("Font 0 (refresh=false)", true)]);
+        assert_eq!(calls.load(Ordering::SeqCst), 1);
+
+        let second = cached(&cache, false, lister);
+        assert!(Arc::ptr_eq(&first, &second));
+        assert_eq!(calls.load(Ordering::SeqCst), 1);
+
+        let refreshed = cached(&cache, true, lister);
+        assert_eq!(&*refreshed, &[fam("Font 1 (refresh=true)", false)]);
+        assert_eq!(calls.load(Ordering::SeqCst), 2);
+
+        let after_refresh = cached(&cache, false, lister);
+        assert!(Arc::ptr_eq(&refreshed, &after_refresh));
+        assert_eq!(calls.load(Ordering::SeqCst), 2);
+    }
+
    /// The real font system: every desktop OS ships some fonts, at least one
    /// of them monospaced, and the list comes back sorted without duplicates.
    #[cfg(any(target_os = "macos", windows))]
    #[test]
    fn lists_installed_families() {
-        let list = families();
+        let list = families(false);
        assert!(list.len() > 20, "only {} families", list.len());
        assert!(list.iter().any(|f| f.monospaced));
        assert!(list.iter().any(|f| !f.monospaced));
@@ -260,5 +536,6 @@ mod tests {
            assert!(menlo.monospaced);
            assert!(list.iter().any(|f| f.name == "Helvetica Neue" && !f.monospaced));
        }
+        assert_eq!(&*families(true), &*list);
    }
 }
@@ -107,7 +107,7 @@ pub fn availability(root: &Path) -> GhAvailability {
    }
    let (repo, login) = std::thread::scope(|s| {
        let repo = s.spawn(|| {
-            let cmd = command(root, &["repo", "view", "--json", "nameWithOwner,url,defaultBranchRef"])?;
+            let cmd = command(root, &["repo", "view", "--json", REPO_FIELDS])?;
            process::run(cmd, QUICK, None)
        });
        let login = s.spawn(|| run(root, &["api", "user", "--jq", ".login"]));
@@ -278,6 +278,53 @@ pub fn add_comment(root: &Path, number: u32, body: &str) -> IdeResult<()> {
    run(root, &["pr", "comment", &n, "--body", body]).map(drop)
 }

+/// A GitHub API call through `gh api`: GraphQL (`endpoint` `graphql`, `body`
+/// `{"query", "variables"}`) or REST (`repos/{owner}/{repo}/…`, gh fills in the
+/// placeholders from the project's remote).
+#[derive(Clone, Debug, PartialEq, Serialize, Deserialize, Type)]
+#[serde(rename_all = "camelCase")]
+pub struct GhApiRequest {
+    /// `GET`, `POST`, `PATCH`, `PUT`, `DELETE`.
+    pub method: String,
+    pub endpoint: String,
+    /// JSON request body, sent on stdin.
+    pub body: Option<String>,
+    /// Follow REST `Link` pages; the result is the array of all pages (`--slurp`).
+    pub paginate: bool,
+}
+
+const METHODS: &[&str] = &["GET", "POST", "PATCH", "PUT", "DELETE"];
+
+/// `gh api` arguments for `req`.
+pub fn api_args(req: &GhApiRequest) -> IdeResult<Vec<String>> {
+    let method = req.method.to_ascii_uppercase();
+    if !METHODS.contains(&method.as_str()) {
+        return Err(IdeError::invalid(format!("unsupported HTTP method {}", req.method)));
+    }
+    let endpoint = req.endpoint.trim();
+    if endpoint.is_empty() || endpoint.starts_with('-') || endpoint.contains("://") {
+        return Err(IdeError::invalid(format!("not a GitHub API endpoint: {endpoint}")));
+    }
+    let mut args: Vec<String> = vec!["api".into(), "--method".into(), method, endpoint.into()];
+    if req.body.is_some() {
+        args.push("--input".into());
+        args.push("-".into());
+    }
+    if req.paginate {
+        args.push("--paginate".into());
+        args.push("--slurp".into());
+    }
+    Ok(args)
+}
+
+/// Runs `req`; returns the response body (JSON text, empty for `204 No Content`).
+pub fn api(root: &Path, req: &GhApiRequest) -> IdeResult<String> {
+    let args = api_args(req)?;
+    let refs: Vec<&str> = args.iter().map(String::as_str).collect();
+    let out = process::run_with_input(command(root, &refs)?, req.body.as_deref(), QUICK, None)?;
+    if out.success { Ok(out.stdout) } else { Err(failure(&out.stderr, &out.stdout)) }
+}
+
 /// Revisions to diff a pull request's files with, present in the local repository.
 #[derive(Clone, Debug, Serialize, Deserialize, Type)]
 #[serde(rename_all = "camelCase")]
@@ -34,6 +34,12 @@ pub struct GhRepo {
    pub name_with_owner: String,
    pub url: String,
    pub default_branch: Option<String>,
+    /// Merge methods the repository allows (all of them when gh does not say).
+    pub merge_commit_allowed: bool,
+    pub squash_merge_allowed: bool,
+    pub rebase_merge_allowed: bool,
+    /// The signed-in user's permission: `ADMIN`, `MAINTAIN`, `WRITE`, `TRIAGE`, `READ`; empty when unknown.
+    pub viewer_permission: String,
 }

 #[derive(Clone, Copy, Debug, PartialEq, Eq, Serialize, Deserialize, Type)]
@@ -152,6 +158,8 @@ pub struct PullRequestDetails {
    pub base_oid: String,
    /// `MERGEABLE`, `CONFLICTING`, `UNKNOWN`.
    pub mergeable: String,
+    /// GitHub's merge box state: `CLEAN`, `UNSTABLE`, `HAS_HOOKS`, `BLOCKED`, `BEHIND`, `DIRTY`, `DRAFT`, `UNKNOWN`.
+    pub merge_state_status: String,
    pub is_cross_repository: bool,
    pub merged_at: Option<String>,
    pub closed_at: Option<String>,
@@ -242,7 +250,7 @@ impl RawSummary {
 pub const LIST_FIELDS: &str = "number,title,author,state,isDraft,headRefName,baseRefName,createdAt,updatedAt,labels,reviewDecision,url,additions,deletions";

 /// Fields requested from `gh pr view`.
-pub const VIEW_FIELDS: &str = "number,title,author,state,isDraft,headRefName,baseRefName,createdAt,updatedAt,labels,reviewDecision,url,additions,deletions,body,headRefOid,baseRefOid,mergeable,isCrossRepository,mergedAt,closedAt,statusCheckRollup,reviewRequests,reviews,assignees,commits,files,comments";
+pub const VIEW_FIELDS: &str = "number,title,author,state,isDraft,headRefName,baseRefName,createdAt,updatedAt,labels,reviewDecision,url,additions,deletions,body,headRefOid,baseRefOid,mergeable,mergeStateStatus,isCrossRepository,mergedAt,closedAt,statusCheckRollup,reviewRequests,reviews,assignees,commits,files,comments";

 pub fn parse_list(json: &str) -> serde_json::Result<Vec<PullRequestSummary>> {
    let raw: Vec<RawSummary> = serde_json::from_str(json)?;
@@ -348,6 +356,7 @@ struct RawDetails {
    head_ref_oid: String,
    base_ref_oid: String,
    mergeable: String,
+    merge_state_status: String,
    is_cross_repository: bool,
    merged_at: Option<String>,
    closed_at: Option<String>,
@@ -442,6 +451,7 @@ pub fn parse_view(json: &str) -> serde_json::Result<PullRequestDetails> {
        head_oid: raw.head_ref_oid,
        base_oid: raw.base_ref_oid,
        mergeable: raw.mergeable,
+        merge_state_status: raw.merge_state_status,
        is_cross_repository: raw.is_cross_repository,
        merged_at: raw.merged_at.filter(|s| !s.is_empty()),
        closed_at: raw.closed_at.filter(|s| !s.is_empty()),
@@ -534,6 +544,10 @@ struct RawRepo {
    name_with_owner: String,
    url: String,
    default_branch_ref: Option<RawBranchRef>,
+    merge_commit_allowed: Option<bool>,
+    squash_merge_allowed: Option<bool>,
+    rebase_merge_allowed: Option<bool>,
+    viewer_permission: Option<String>,
 }

 #[derive(Deserialize, Default)]
@@ -542,13 +556,21 @@ struct RawBranchRef {
    name: String,
 }

-/// `gh repo view --json nameWithOwner,url,defaultBranchRef`.
+/// Fields requested from `gh repo view`.
+pub const REPO_FIELDS: &str =
+    "nameWithOwner,url,defaultBranchRef,mergeCommitAllowed,squashMergeAllowed,rebaseMergeAllowed,viewerPermission";
+
+/// `gh repo view --json` with [`REPO_FIELDS`].
 pub fn parse_repo(json: &str) -> serde_json::Result<GhRepo> {
    let raw: RawRepo = serde_json::from_str(json)?;
    Ok(GhRepo {
        name_with_owner: raw.name_with_owner,
        url: raw.url,
        default_branch: raw.default_branch_ref.map(|b| b.name).filter(|n| !n.is_empty()),
+        merge_commit_allowed: raw.merge_commit_allowed.unwrap_or(true),
+        squash_merge_allowed: raw.squash_merge_allowed.unwrap_or(true),
+        rebase_merge_allowed: raw.rebase_merge_allowed.unwrap_or(true),
+        viewer_permission: raw.viewer_permission.unwrap_or_default(),
    })
 }

@@ -60,9 +60,30 @@ fn read_all(mut pipe: impl Read + Send + 'static) -> std::thread::JoinHandle<Str

 /// Runs `cmd` to completion. Fails when it outlives `timeout` or `cancel` fires;
 /// a non-zero exit is reported in [`Output::success`], not as an error.
-pub(crate) fn run(mut cmd: Command, timeout: Duration, cancel: Option<&CancellationToken>) -> IdeResult<Output> {
+pub(crate) fn run(cmd: Command, timeout: Duration, cancel: Option<&CancellationToken>) -> IdeResult<Output> {
+    run_with_input(cmd, None, timeout, cancel)
+}
+
+/// [`run`] with `input` written to the child's stdin (then closed).
+pub(crate) fn run_with_input(
+    mut cmd: Command,
+    input: Option<&str>,
+    timeout: Duration,
+    cancel: Option<&CancellationToken>,
+) -> IdeResult<Output> {
    prepare(&mut cmd);
+    if input.is_some() {
+        cmd.stdin(Stdio::piped());
+    }
    let mut child = spawn(&mut cmd)?;
+    if let (Some(input), Some(mut stdin)) = (input, child.stdin.take()) {
+        let input = input.to_owned();
+        // A writer thread: a large body must not block on a full pipe while gh is not reading yet.
+        std::thread::spawn(move || {
+            use std::io::Write;
+            let _ = stdin.write_all(input.as_bytes());
+        });
+    }
    let out = child.stdout.take().map(read_all);
    let err = child.stderr.take().map(read_all);
    let deadline = Instant::now() + timeout;
@@ -1 +1 @@
-{"additions":42,"assignees":[],"author":{"id":"MDQ6VXNlcjM2NzI4OTMx","is_bot":false,"login":"babakks","name":"Babak K. Shandiz"},"baseRefName":"trunk","baseRefOid":"ae7b9715976c5508398b11dc8546e1279e10f6fc","body":"### Description\n\nThis PR moves gh to the tagged version of `cli/oauth`.","closedAt":"2026-10-21T12:29:58Z","comments":[{"id":"IC_1","author":{"login":"babakks"},"authorAssociation":"MEMBER","body":"Rebased on trunk.","createdAt":"2026-10-21T08:00:00Z","includesCreatedEdit":false,"isMinimized":false,"minimizedReason":"","reactionGroups":[],"url":"https://github.com/cli/cli/pull/14768#issuecomment-1","viewerDidAuthor":false}],"commits":[{"authoredDate":"2026-10-20T16:37:24Z","authors":[{"email":"[email protected]","id":"MDQ6VXNlcjM2NzI4OTMx","login":"babakks","name":"Babak K. Shandiz"}],"committedDate":"2026-10-21T12:06:51Z","messageBody":"cli/oauth v1.3.0 exposes the token expiry fields as time.Duration values.","messageHeadline":"chore(deps): bump github.com/cli/oauth to v1.3.0","oid":"fd1b1feb222dde885d00262b2c21b107c6c6e416"}],"createdAt":"2026-10-20T16:40:41Z","deletions":48,"files":[{"path":"go.mod","additions":1,"deletions":1,"changeType":"MODIFIED"},{"path":"pkg/cmd/status/status.go","additions":3,"deletions":2,"changeType":"MODIFIED"}],"headRefName":"babakks/refresh-token-bump-deps","headRefOid":"6ec1ba54542baca6cc5932582634104c83f36a28","isCrossRepository":false,"isDraft":false,"labels":[],"mergeable":"UNKNOWN","mergedAt":"2026-10-21T12:29:58Z","number":14768,"reviewDecision":"APPROVED","reviewRequests":[{"__typename":"User","login":"niik"}],"reviews":[{"id":"PRR_1","author":{"login":"copilot-pull-request-reviewer"},"authorAssociation":"CONTRIBUTOR","body":"","submittedAt":"2026-10-21T09:46:01Z","includesCreatedEdit":false,"reactionGroups":[],"state":"COMMENTED","commit":{"oid":"831b9343fa77c2f11f521a49fd01da2d2d007b8e"}},{"id":"PRR_2","author":{"login":"williammartin"},"authorAssociation":"MEMBER","body":"LGTM","submittedAt":"2026-10-21T12:20:00Z","includesCreatedEdit":false,"reactionGroups":[],"state":"APPROVED","commit":{"oid":"6ec1ba54542baca6cc5932582634104c83f36a28"}}],"state":"MERGED","statusCheckRollup":[{"__typename":"CheckRun","completedAt":"2026-10-21T12:09:03Z","conclusion":"SUCCESS","detailsUrl":"https://github.com/cli/cli/actions/runs/1/job/1","name":"build (ubuntu)","startedAt":"2026-10-21T12:07:01Z","status":"COMPLETED","workflowName":"Tests"},{"__typename":"CheckRun","completedAt":"0001-01-01T00:00:00Z","conclusion":"","detailsUrl":"https://github.com/cli/cli/actions/runs/1/job/2","name":"build (windows)","startedAt":"2026-10-21T12:07:01Z","status":"IN_PROGRESS","workflowName":"Tests"},{"__typename":"CheckRun","completedAt":"2026-10-21T12:08:00Z","conclusion":"FAILURE","detailsUrl":"https://github.com/cli/cli/actions/runs/1/job/3","name":"lint","startedAt":"2026-10-21T12:07:01Z","status":"COMPLETED","workflowName":"Lint"},{"__typename":"CheckRun","completedAt":"2026-10-21T12:08:00Z","conclusion":"SKIPPED","detailsUrl":"","name":"docs","startedAt":"2026-10-21T12:07:01Z","status":"COMPLETED","workflowName":""},{"__typename":"StatusContext","context":"ci/legacy","state":"PENDING","targetUrl":"https://ci.example.com/1","startedAt":"2026-10-21T12:07:01Z"}],"title":"Refreshable tokens: bump cli/oauth to v1.3.0 and fix `gh status` column width","updatedAt":"2026-10-21T12:30:00Z","url":"https://github.com/cli/cli/pull/14768"}
+{"additions":42,"assignees":[],"author":{"id":"MDQ6VXNlcjM2NzI4OTMx","is_bot":false,"login":"babakks","name":"Babak K. Shandiz"},"baseRefName":"trunk","baseRefOid":"ae7b9715976c5508398b11dc8546e1279e10f6fc","body":"### Description\n\nThis PR moves gh to the tagged version of `cli/oauth`.","closedAt":"2026-10-21T12:29:58Z","comments":[{"id":"IC_1","author":{"login":"babakks"},"authorAssociation":"MEMBER","body":"Rebased on trunk.","createdAt":"2026-10-21T08:00:00Z","includesCreatedEdit":false,"isMinimized":false,"minimizedReason":"","reactionGroups":[],"url":"https://github.com/cli/cli/pull/14768#issuecomment-1","viewerDidAuthor":false}],"commits":[{"authoredDate":"2026-10-20T16:37:24Z","authors":[{"email":"[email protected]","id":"MDQ6VXNlcjM2NzI4OTMx","login":"babakks","name":"Babak K. Shandiz"}],"committedDate":"2026-10-21T12:06:51Z","messageBody":"cli/oauth v1.3.0 exposes the token expiry fields as time.Duration values.","messageHeadline":"chore(deps): bump github.com/cli/oauth to v1.3.0","oid":"fd1b1feb222dde885d00262b2c21b107c6c6e416"}],"createdAt":"2026-10-20T16:40:41Z","deletions":48,"files":[{"path":"go.mod","additions":1,"deletions":1,"changeType":"MODIFIED"},{"path":"pkg/cmd/status/status.go","additions":3,"deletions":2,"changeType":"MODIFIED"}],"headRefName":"babakks/refresh-token-bump-deps","headRefOid":"6ec1ba54542baca6cc5932582634104c83f36a28","isCrossRepository":false,"isDraft":false,"labels":[],"mergeable":"UNKNOWN","mergeStateStatus":"UNKNOWN","mergedAt":"2026-10-21T12:29:58Z","number":14768,"reviewDecision":"APPROVED","reviewRequests":[{"__typename":"User","login":"niik"}],"reviews":[{"id":"PRR_1","author":{"login":"copilot-pull-request-reviewer"},"authorAssociation":"CONTRIBUTOR","body":"","submittedAt":"2026-10-21T09:46:01Z","includesCreatedEdit":false,"reactionGroups":[],"state":"COMMENTED","commit":{"oid":"831b9343fa77c2f11f521a49fd01da2d2d007b8e"}},{"id":"PRR_2","author":{"login":"williammartin"},"authorAssociation":"MEMBER","body":"LGTM","submittedAt":"2026-10-21T12:20:00Z","includesCreatedEdit":false,"reactionGroups":[],"state":"APPROVED","commit":{"oid":"6ec1ba54542baca6cc5932582634104c83f36a28"}}],"state":"MERGED","statusCheckRollup":[{"__typename":"CheckRun","completedAt":"2026-10-21T12:09:03Z","conclusion":"SUCCESS","detailsUrl":"https://github.com/cli/cli/actions/runs/1/job/1","name":"build (ubuntu)","startedAt":"2026-10-21T12:07:01Z","status":"COMPLETED","workflowName":"Tests"},{"__typename":"CheckRun","completedAt":"0001-01-01T00:00:00Z","conclusion":"","detailsUrl":"https://github.com/cli/cli/actions/runs/1/job/2","name":"build (windows)","startedAt":"2026-10-21T12:07:01Z","status":"IN_PROGRESS","workflowName":"Tests"},{"__typename":"CheckRun","completedAt":"2026-10-21T12:08:00Z","conclusion":"FAILURE","detailsUrl":"https://github.com/cli/cli/actions/runs/1/job/3","name":"lint","startedAt":"2026-10-21T12:07:01Z","status":"COMPLETED","workflowName":"Lint"},{"__typename":"CheckRun","completedAt":"2026-10-21T12:08:00Z","conclusion":"SKIPPED","detailsUrl":"","name":"docs","startedAt":"2026-10-21T12:07:01Z","status":"COMPLETED","workflowName":""},{"__typename":"StatusContext","context":"ci/legacy","state":"PENDING","targetUrl":"https://ci.example.com/1","startedAt":"2026-10-21T12:07:01Z"}],"title":"Refreshable tokens: bump cli/oauth to v1.3.0 and fix `gh status` column width","updatedAt":"2026-10-21T12:30:00Z","url":"https://github.com/cli/cli/pull/14768"}
@@ -22,6 +22,7 @@ fn pr_view() {
    assert_eq!(pr.summary.number, 14768);
    assert_eq!(pr.summary.head_ref, "babakks/refresh-token-bump-deps");
    assert_eq!(pr.head_oid, "6ec1ba54542baca6cc5932582634104c83f36a28");
+    assert_eq!(pr.merge_state_status, "UNKNOWN");
    assert_eq!(pr.files.len(), 2);
    assert_eq!(pr.files[0].change_type, "MODIFIED");
    assert_eq!(pr.commits[0].headline, "chore(deps): bump github.com/cli/oauth to v1.3.0");
@@ -69,6 +70,16 @@ fn repo_view() {
        .unwrap();
    assert_eq!(r.name_with_owner, "l0ng-ai/openidea");
    assert_eq!(r.default_branch.as_deref(), Some("main"));
+    assert!(r.merge_commit_allowed && r.squash_merge_allowed && r.rebase_merge_allowed, "unknown: allowed");
+    assert_eq!(r.viewer_permission, "");
+
+    let r = parse_repo(
+        r#"{"mergeCommitAllowed":true,"nameWithOwner":"o/r","url":"","rebaseMergeAllowed":false,"squashMergeAllowed":false,"viewerPermission":"WRITE"}"#,
+    )
+    .unwrap();
+    assert!(r.merge_commit_allowed);
+    assert!(!r.squash_merge_allowed && !r.rebase_merge_allowed);
+    assert_eq!(r.viewer_permission, "WRITE");
 }

 #[test]
@@ -87,3 +98,24 @@ fn list_arguments() {
    assert!(joined.contains("--limit 500 --state merged --author @me"));
    assert_eq!(args.last().map(String::as_str), Some("review-requested:@me fix login"));
 }
+
+#[test]
+fn api_arguments() {
+    let req =
+        GhApiRequest { method: "post".into(), endpoint: "graphql".into(), body: Some("{}".into()), paginate: false };
+    assert_eq!(api_args(&req).unwrap(), ["api", "--method", "POST", "graphql", "--input", "-"]);
+    let req = GhApiRequest {
+        method: "GET".into(),
+        endpoint: "repos/{owner}/{repo}/labels".into(),
+        body: None,
+        paginate: true,
+    };
+    assert_eq!(
+        api_args(&req).unwrap(),
+        ["api", "--method", "GET", "repos/{owner}/{repo}/labels", "--paginate", "--slurp"]
+    );
+    for bad in ["--hostname", "https://evil.example/x", ""] {
+        assert!(api_args(&GhApiRequest { endpoint: bad.into(), ..req.clone() }).is_err(), "{bad}");
+    }
+    assert!(api_args(&GhApiRequest { method: "TRACE".into(), ..req }).is_err());
+}
@@ -10,6 +10,7 @@ name = "openidea-server"
 path = "src/bin/server.rs"

 [dependencies]
+encoding_rs.workspace = true
 ide-core.workspace = true
 ide-text.workspace = true
 ide-vfs.workspace = true
@@ -34,17 +35,20 @@ ide-ssh.workspace = true
 ide-remote.workspace = true
 ide-jsonrpc.workspace = true
 ide-agent.workspace = true
+ide-notebook.workspace = true
 ide-tools = { path = "../ide-tools" }
 serde.workspace = true
 serde_json.workspace = true
 specta.workspace = true
+specta-typescript.workspace = true
 tokio = { workspace = true, features = ["io-std"] }
 tracing.workspace = true
 tracing-subscriber.workspace = true
 parking_lot.workspace = true
 dunce.workspace = true
 dirs.workspace = true
+uuid.workspace = true
+tempfile.workspace = true

 [dev-dependencies]
-tokio = { workspace = true, features = ["rt-multi-thread", "macros", "io-util"] }
-tempfile.workspace = true
+tokio = { workspace = true, features = ["rt-multi-thread", "macros", "io-util", "test-util"] }
@@ -44,6 +44,7 @@ struct State {
    project: Changes,
    /// Project roots whose `postStartCommand` ran in this process.
    post_started: HashSet<PathBuf>,
+    post_commands: std::collections::HashMap<PathBuf, CancellationToken>,
 }

 pub struct Environment {
@@ -78,7 +79,12 @@ impl Environment {

    pub(crate) fn project_closed(&self) {
        if self.project_env {
-            self.state.lock().project.clear();
+            let mut state = self.state.lock();
+            for (_, token) in state.post_commands.drain() {
+                token.cancel();
+            }
+            state.project.clear();
+            drop(state);
            self.publish();
        }
    }
@@ -144,6 +150,7 @@ impl Environment {
    /// a failure is a notification.
    pub(crate) fn spawn_post_start(&self, cmd: LifecycleCommand, root: PathBuf, sink: SharedSink) {
        let cancel = self.cancel.child_token();
+        self.state.lock().post_commands.insert(root.clone(), cancel.clone());
        let spawned = std::thread::Builder::new().name("openidea-post-start".into()).spawn(move || {
            run_post_start(&cmd, &root, &sink, &cancel);
        });
@@ -263,6 +270,9 @@ fn run_post_start(cmd: &LifecycleCommand, root: &Path, sink: &SharedSink, cancel
 /// Runs `argv` in `root` with the children's environment, its stdout and stderr line by line
 /// to `on_line`; `Err` says how it failed.
 fn run_one(argv: &[String], root: &Path, cancel: &CancellationToken, on_line: &dyn Fn(String)) -> Result<(), String> {
+    if cancel.is_cancelled() {
+        return Err("cancelled".into());
+    }
    let (program, args) = argv.split_first().ok_or("empty command")?;
    let mut child = ide_core::process::prepare(&mut Command::new(program))
        .args(args)
@@ -281,7 +291,8 @@ fn run_one(argv: &[String], root: &Path, cancel: &CancellationToken, on_line: &d
    for pipe in pipes.into_iter().flatten() {
        let tx = tx.clone();
        std::thread::spawn(move || {
-            for line in BufReader::new(pipe).lines().map_while(Result::ok) {
+            for line in BufReader::new(pipe).split(b'\n').map_while(Result::ok) {
+                let line = ide_core::output_encoding::decode_tool_output(&line).trim_end_matches('\r').to_owned();
                if tx.send(line).is_err() {
                    break;
                }
@@ -0,0 +1,107 @@
+//! Select the document's formatting provider before executing it on this host.
+
+use crate::Host;
+use ide_core::event::NotifyLevel;
+use ide_core::settings::PrettierSettings;
+use ide_core::{DocId, IdeError, IdeEvent, IdeResult, Range, TextEdit};
+use ide_language::FormatterConfig;
+use ide_lsp::types::FormatOptions;
+use ide_tools::{Tools, formatter};
+
+fn external_selected(config: Option<&FormatterConfig>, language: &str, settings: &PrettierSettings, lsp: bool) -> bool {
+    config.is_some_and(|c| c.tool == "prettier")
+        && settings.languages.iter().any(|l| l == language)
+        && (settings.prefer || !lsp)
+}
+
+pub async fn format(
+    host: &Host,
+    window: &str,
+    doc: DocId,
+    range: Option<Range>,
+    options: FormatOptions,
+) -> IdeResult<Vec<TextEdit>> {
+    let project = host.project(window)?;
+    let snap = project.documents.snapshot(doc)?;
+    let settings = project.settings.effective();
+    let prettier = &settings.languages.prettier;
+    let language = project.languages.get(&snap.language);
+    let config = language.as_ref().and_then(|l| l.formatter.as_ref());
+    let candidate =
+        config.is_some_and(|c| c.tool == "prettier") && prettier.languages.iter().any(|l| l == snap.language.as_str());
+    let lsp = if candidate && !prettier.prefer { project.lsp.can_format(doc).await? } else { false };
+    if !external_selected(config, snap.language.as_str(), prettier, lsp) {
+        if options.on_save && !settings.editor.format_on_save {
+            return Ok(Vec::new());
+        }
+        return project.lsp.format(doc, range, options).await;
+    }
+    if options.on_save && !prettier.run_on_save {
+        return Ok(Vec::new());
+    }
+    host.require_trust(window)?;
+    if snap.read_only {
+        return Err(IdeError::invalid("The file is read-only"));
+    }
+    let config = config.unwrap().clone();
+    let custom = ide_sdk::apply::setting_path(&project.root, &prettier.path);
+    let tools = Tools::new(&host.data_dir);
+    let whole_selection = range.is_some() && !config.range;
+    let edits: IdeResult<Vec<TextEdit>> = tokio::task::spawn_blocking(move || {
+        let text = ide_text::Document::new(&snap.text);
+        let offsets = range.map(|r| (text.pos_to_offset(r.start), text.pos_to_offset(r.end)));
+        let mut command = tools.formatter_command(&config.tool, &snap.path, custom.as_deref())?;
+        command.current_dir(snap.path.parent().ok_or_else(|| IdeError::invalid("Prettier: file has no directory"))?);
+        command.args(formatter::arguments(&config, &snap.path, options.tab_size, options.insert_spaces, offsets));
+        let formatted = formatter::run(command, &snap.text, &Default::default())?;
+        Ok(text
+            .diff(&formatted)
+            .changes
+            .into_iter()
+            .map(|c| TextEdit {
+                range: Range::new(text.offset_to_pos(c.from), text.offset_to_pos(c.to)),
+                new_text: c.insert,
+            })
+            .collect())
+    })
+    .await
+    .map_err(|e| IdeError::internal(e.to_string()))?;
+    if edits.is_ok() && whole_selection {
+        project.sink.emit(IdeEvent::Notify {
+            level: NotifyLevel::Info,
+            title: "Prettier".into(),
+            body: Some(
+                "Prettier does not support selection formatting for this language; formatted the whole file".into(),
+            ),
+        });
+    }
+    edits.map_err(|e| e.with_tool("prettier"))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn language_enablement_and_preference_preserve_lsp_formatters() {
+        let languages = ide_language::LanguageRegistry::load(None).unwrap();
+        let mut settings = PrettierSettings::default();
+        for lang in languages.all() {
+            for lsp in [false, true] {
+                let configured = lang.formatter.as_ref().is_some_and(|f| f.tool == "prettier");
+                assert_eq!(
+                    external_selected(lang.formatter.as_ref(), lang.id.as_str(), &settings, lsp),
+                    configured && !lsp,
+                    "{}",
+                    lang.id
+                );
+            }
+        }
+        let ts = languages.get(&ide_core::LanguageId::new("typescript")).unwrap();
+        settings.prefer = true;
+        assert!(external_selected(ts.formatter.as_ref(), "typescript", &settings, true));
+        settings.languages.clear();
+        assert!(!external_selected(ts.formatter.as_ref(), "typescript", &settings, false));
+        assert!(!external_selected(None, "rust", &settings, false));
+    }
+}
@@ -0,0 +1,183 @@
+//! Automatic runtime provisioning belongs to the host, not SDK discovery.
+use ide_core::{CancellationToken, IdeEvent, SharedSink, TaskId};
+use ide_language::LanguageServerConfig;
+use ide_sdk::java::{jdtls_jdks, jdtls_min_java, jdtls_runtime, language_server_runtimes_dir};
+use parking_lot::{Condvar, Mutex};
+use std::collections::HashSet;
+use std::path::{Path, PathBuf};
+use std::sync::{Arc, LazyLock, Weak};
+use std::time::Duration;
+
+#[derive(Default)]
+struct State {
+    busy: bool,
+    sinks: Vec<Weak<dyn ide_core::EventSink>>,
+    attempted: HashSet<(PathBuf, u32)>,
+}
+
+#[derive(Default)]
+struct Provisioner {
+    state: Mutex<State>,
+    changed: Condvar,
+}
+
+static PROVISIONER: LazyLock<Provisioner> = LazyLock::new(Provisioner::default);
+
+fn needs_download(explicit: bool, suitable: bool, attempted: bool) -> bool {
+    !explicit && !suitable && !attempted
+}
+
+impl Provisioner {
+    fn subscribe(&self, sink: &SharedSink) {
+        let mut state = self.state.lock();
+        state.sinks.retain(|s| s.strong_count() > 0);
+        let weak = Arc::downgrade(sink);
+        if !state.sinks.iter().any(|s| s.ptr_eq(&weak)) {
+            state.sinks.push(weak);
+        }
+    }
+
+    fn emit(&self, event: IdeEvent) {
+        let sinks: Vec<_> = self.state.lock().sinks.iter().filter_map(Weak::upgrade).collect();
+        for sink in sinks {
+            sink.emit(event.clone());
+        }
+    }
+
+    fn run(&self, key: (PathBuf, u32), cancel: &CancellationToken, work: impl FnOnce()) {
+        let mut state = self.state.lock();
+        while state.busy && !cancel.is_cancelled() {
+            self.changed.wait_for(&mut state, Duration::from_millis(100));
+        }
+        if cancel.is_cancelled() || !state.attempted.insert(key) {
+            return;
+        }
+        state.busy = true;
+        drop(state);
+        // Even a panicking installer must release waiters and retain the attempt.
+        struct Flight<'a>(&'a Provisioner);
+        impl Drop for Flight<'_> {
+            fn drop(&mut self) {
+                self.0.state.lock().busy = false;
+                self.0.changed.notify_all();
+            }
+        }
+        let _flight = Flight(self);
+        work();
+    }
+}
+
+pub(crate) fn prepare(
+    cfg: &LanguageServerConfig,
+    data_dir: &Path,
+    explicit: bool,
+    sink: &SharedSink,
+    launch_cancel: &CancellationToken,
+) {
+    let min_java = jdtls_min_java(cfg);
+    let jdks = jdtls_jdks(min_java, data_dir);
+    // A launch environment override is explicit too, even if it is invalid.
+    if !needs_download(explicit || cfg.env.contains_key("JAVA_HOME"), jdtls_runtime(&jdks, min_java).is_some(), false) {
+        return;
+    }
+    PROVISIONER.subscribe(sink);
+    PROVISIONER.run((data_dir.to_path_buf(), min_java), launch_cancel, || {
+        if jdtls_runtime(&jdtls_jdks(min_java, data_dir), min_java).is_some() {
+            return;
+        }
+        let id = TaskId::next();
+        let title = format!("Downloading Java {min_java} language server runtime");
+        // Closing one project must not cancel a download other projects await.
+        let cancel = CancellationToken::new();
+        let _handle = ide_core::task::on_cancel(id, {
+            let cancel = cancel.clone();
+            move || cancel.cancel()
+        });
+        let emit = |message, fraction, done| {
+            PROVISIONER.emit(IdeEvent::Task { id, title: title.clone(), message, fraction, done, cancellable: !done });
+        };
+        emit(Some("Eclipse Temurin".into()), None, false);
+        let result = ide_tools::Tools::new(data_dir).download_java_runtime(
+            min_java,
+            &language_server_runtimes_dir(data_dir),
+            &cancel,
+            &|event| match event {
+                ide_tools::InstallEvent::Line { text } => emit(Some(text), None, false),
+                ide_tools::InstallEvent::Progress { fraction, message } => {
+                    emit(Some(message), fraction.map(|f| f as f32), false)
+                }
+            },
+        );
+        emit(result.as_ref().err().map(ToString::to_string), Some(1.0), true);
+        if let Err(error) = result {
+            // The configuration hook retains the existing manual download action.
+            tracing::warn!("automatic jdtls runtime download: {error}");
+        }
+    });
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::sync::atomic::{AtomicUsize, Ordering};
+
+    #[test]
+    fn download_decision() {
+        assert!(needs_download(false, false, false));
+        for (explicit, suitable, attempted) in [(true, false, false), (false, true, false), (false, false, true)] {
+            assert!(!needs_download(explicit, suitable, attempted));
+        }
+    }
+
+    #[test]
+    fn simultaneous_projects_share_one_attempt_and_failures_do_not_retry() {
+        let provisioner = Provisioner::default();
+        let calls = AtomicUsize::new(0);
+        let barrier = std::sync::Barrier::new(8);
+        std::thread::scope(|scope| {
+            for _ in 0..8 {
+                scope.spawn(|| {
+                    barrier.wait();
+                    provisioner.run((PathBuf::from("/data"), 25), &CancellationToken::new(), || {
+                        calls.fetch_add(1, Ordering::SeqCst);
+                        std::thread::sleep(Duration::from_millis(30));
+                    });
+                });
+            }
+        });
+        provisioner.run((PathBuf::from("/data"), 25), &CancellationToken::new(), || panic!("retried"));
+        assert_eq!(calls.load(Ordering::SeqCst), 1);
+    }
+
+    #[test]
+    fn different_versions_are_still_single_flight() {
+        let provisioner = Provisioner::default();
+        let active = AtomicUsize::new(0);
+        let calls = AtomicUsize::new(0);
+        std::thread::scope(|scope| {
+            for feature in [25, 26, 27] {
+                let provisioner = &provisioner;
+                let active = &active;
+                let calls = &calls;
+                scope.spawn(move || {
+                    provisioner.run((PathBuf::from("/data"), feature), &CancellationToken::new(), || {
+                        assert_eq!(active.fetch_add(1, Ordering::SeqCst), 0);
+                        std::thread::sleep(Duration::from_millis(10));
+                        calls.fetch_add(1, Ordering::SeqCst);
+                        active.fetch_sub(1, Ordering::SeqCst);
+                    });
+                });
+            }
+        });
+        assert_eq!(calls.load(Ordering::SeqCst), 3);
+    }
+
+    #[test]
+    fn cancelled_waiter_does_not_consume_an_attempt() {
+        let provisioner = Provisioner::default();
+        let cancel = CancellationToken::new();
+        cancel.cancel();
+        provisioner.run((PathBuf::from("/data"), 25), &cancel, || panic!("cancelled"));
+        assert!(provisioner.state.lock().attempted.is_empty());
+    }
+}
@@ -0,0 +1,429 @@
+//! Saved Kotlin -> isolated Maven output -> marked JDT libraries.
+
+use ide_build::kotlin_bridge::{self, Outcome, ProjectLibraries};
+use ide_core::event::NotifyLevel;
+use ide_core::{CancellationToken, Diagnostic, IdeEvent, Pos, Range, Severity, SharedSink};
+use ide_lsp::LspManager;
+use ide_workspace::SettingsStore;
+use ide_workspace::documents::DocumentObserver;
+use parking_lot::Mutex;
+use serde::{Deserialize, Serialize};
+use std::collections::BTreeSet;
+use std::path::{Path, PathBuf};
+use std::sync::{
+    Arc,
+    atomic::{AtomicBool, Ordering},
+};
+use std::time::Duration;
+use tokio::sync::Notify;
+
+const DELAY: Duration = Duration::from_millis(750);
+const SOURCE: &str = "kotlin-bridge";
+const COMMAND: &str = "openidea.kotlin.replace";
+
+#[derive(Default)]
+struct Revision {
+    generation: u64,
+    cancel: CancellationToken,
+}
+
+impl Revision {
+    fn change(&mut self) {
+        self.cancel.cancel();
+        self.generation += 1;
+        self.cancel = CancellationToken::new();
+    }
+    fn current(&self, generation: u64) -> bool {
+        self.generation == generation && !self.cancel.is_cancelled()
+    }
+}
+
+#[derive(Clone, Default, Serialize, Deserialize)]
+struct MavenOptions {
+    offline: bool,
+    profiles: Vec<String>,
+}
+
+pub(crate) struct KotlinBridge {
+    root: PathBuf,
+    cache: PathBuf,
+    bundle: Option<PathBuf>,
+    settings: Arc<SettingsStore>,
+    lsp: Arc<LspManager>,
+    sink: SharedSink,
+    trusted: Arc<AtomicBool>,
+    lifetime: CancellationToken,
+    revision: Mutex<Revision>,
+    changed: Notify,
+    options: Mutex<MavenOptions>,
+    worker: Mutex<Option<tokio::task::JoinHandle<()>>>,
+}
+
+impl KotlinBridge {
+    pub(crate) fn new(
+        root: PathBuf,
+        cache: PathBuf,
+        data: &Path,
+        settings: Arc<SettingsStore>,
+        lsp: Arc<LspManager>,
+        sink: SharedSink,
+        trusted: Arc<AtomicBool>,
+    ) -> Arc<Self> {
+        let options = std::fs::read(cache.join("kotlin-bridge-options.json"))
+            .ok()
+            .and_then(|bytes| serde_json::from_slice(&bytes).ok())
+            .unwrap_or_default();
+        Arc::new(Self {
+            root,
+            cache,
+            bundle: ide_sdk::java::kotlin_bridge_bundle(data),
+            settings,
+            lsp,
+            sink,
+            trusted,
+            lifetime: CancellationToken::new(),
+            revision: Mutex::new(Revision::default()),
+            changed: Notify::new(),
+            options: Mutex::new(options),
+            worker: Mutex::new(None),
+        })
+    }
+
+    pub(crate) fn start(self: &Arc<Self>, runtime: &tokio::runtime::Handle) {
+        let bridge = self.clone();
+        *self.worker.lock() = Some(runtime.spawn(async move { bridge.run().await }));
+        self.schedule();
+    }
+
+    pub(crate) fn configure_maven(&self, offline: bool, profiles: Vec<String>) {
+        let options = MavenOptions { offline, profiles };
+        if let Ok(bytes) = serde_json::to_vec(&options) {
+            let _ = std::fs::create_dir_all(&self.cache);
+            let _ = std::fs::write(self.cache.join("kotlin-bridge-options.json"), bytes);
+        }
+        *self.options.lock() = options;
+        self.schedule();
+    }
+
+    pub(crate) async fn shutdown(&self) {
+        self.stop();
+        let worker = self.worker.lock().take();
+        if let Some(worker) = worker {
+            let _ = worker.await;
+        }
+    }
+
+    pub(crate) fn schedule(&self) {
+        if self.lifetime.is_cancelled() {
+            return;
+        }
+        self.revision.lock().change();
+        self.changed.notify_one();
+    }
+
+    pub(crate) fn files_changed<'a>(&self, mut paths: impl Iterator<Item = &'a PathBuf>) {
+        let settings = self.settings.effective();
+        if paths.any(|path| relevant_change(&self.root, path, &settings)) {
+            self.schedule();
+        }
+    }
+
+    pub(crate) fn stop(&self) {
+        self.lifetime.cancel();
+        self.revision.lock().cancel.cancel();
+    }
+
+    async fn replace(&self, projects: &[ProjectLibraries], cancel: &CancellationToken) -> ide_core::IdeResult<()> {
+        let snapshot = serde_json::to_value(projects).map_err(|e| ide_core::IdeError::internal(e.to_string()))?;
+        let response = self.lsp.jdtls_command_cancellable(&self.root, COMMAND, vec![snapshot], cancel).await?;
+        if response.as_u64().is_none() {
+            return Err(ide_core::IdeError::unavailable(
+                "Kotlin bridge command did not acknowledge its library snapshot",
+            ));
+        }
+        Ok(())
+    }
+
+    async fn run(self: Arc<Self>) {
+        let mut diagnostics = BTreeSet::new();
+        let mut last_failure = String::new();
+        let mut initialized = false;
+        // Also retain directories from unacknowledged replacements: JDT may have applied them.
+        let mut published = Vec::new();
+        loop {
+            tokio::select! {
+                _ = self.lifetime.cancelled() => return,
+                _ = self.changed.notified() => {},
+            }
+            let (generation, cancel) = {
+                let state = self.revision.lock();
+                (state.generation, state.cancel.clone())
+            };
+            if !self.trusted.load(Ordering::Acquire) {
+                continue;
+            }
+            if !debounce(&cancel, &self.lifetime).await {
+                continue;
+            }
+            let root = self.root.clone();
+            let cache = self.cache.clone();
+            let settings = self.settings.effective();
+            let has_sources = tokio::task::spawn_blocking(move || {
+                let model = crate::ops::build::load(&root, &cache, &settings);
+                let enabled =
+                    model.maven.as_ref().is_some_and(|m| !m.projects.is_empty()) && kotlin_bridge::has_kotlin(&root);
+                (model, enabled)
+            })
+            .await;
+            let Ok((mut model, enabled)) = has_sources else { continue };
+            if !self.revision.lock().current(generation) {
+                continue;
+            }
+            if !enabled {
+                if self.cache.join("kotlin-bridge").exists()
+                    && let Err(error) = self.replace(&[], &cancel).await
+                {
+                    if !cancel.is_cancelled() {
+                        tracing::warn!("Kotlin library withdrawal: {error}");
+                    }
+                    continue;
+                }
+                for old in published.drain(..) {
+                    remove_directory(old).await;
+                }
+                self.clear_diagnostics(&mut diagnostics);
+                last_failure.clear();
+                continue;
+            }
+            if let Some(maven) = &mut model.maven {
+                let options = self.options.lock();
+                for module in &mut maven.projects {
+                    if options.offline {
+                        module.options.push("-o".into());
+                    }
+                    if !options.profiles.is_empty() {
+                        module.options.push(format!("-P{}", options.profiles.join(",")));
+                    }
+                }
+            }
+            let Some(bundle) = self.bundle.clone() else {
+                self.failure("Kotlin bridge bundle is unavailable".into(), &mut diagnostics, &mut last_failure);
+                continue;
+            };
+            // Clear entries persisted by an earlier incarnation only before our first build.
+            if !initialized {
+                if let Err(error) = self.replace(&[], &cancel).await {
+                    if !cancel.is_cancelled() {
+                        self.failure(error.message, &mut diagnostics, &mut last_failure);
+                    }
+                    continue;
+                }
+                initialized = true;
+            }
+            let directory = self.cache.join(format!("kotlin-bridge/{}", uuid::Uuid::new_v4()));
+            let staging = directory.clone();
+            let root = self.root.clone();
+            let token = cancel.clone();
+            let result =
+                tokio::task::spawn_blocking(move || kotlin_bridge::build(&root, &model, &bundle, &staging, &token))
+                    .await;
+            if !self.revision.lock().current(generation) || self.lifetime.is_cancelled() {
+                remove_directory(directory).await;
+                continue;
+            }
+            match result {
+                Ok(Ok(Outcome { success: true, projects, .. })) => {
+                    match self.replace(&projects, &cancel).await {
+                        Ok(()) => {
+                            for old in published.drain(..) {
+                                remove_directory(old).await;
+                            }
+                            published.push(directory);
+                            self.clear_diagnostics(&mut diagnostics);
+                            last_failure.clear();
+                        }
+                        Err(error) => {
+                            // Keep both snapshots until an acknowledged replacement.
+                            published.push(directory);
+                            if !cancel.is_cancelled() {
+                                self.failure(error.message, &mut diagnostics, &mut last_failure);
+                            }
+                        }
+                    }
+                }
+                other => {
+                    let text = match other {
+                        Ok(Ok(outcome)) => outcome
+                            .messages
+                            .iter()
+                            .filter(|m| m.severity == Severity::Error)
+                            .map(|m| m.text.as_str())
+                            .collect::<Vec<_>>()
+                            .join("\n"),
+                        Ok(Err(error)) => error.message,
+                        Err(error) => error.to_string(),
+                    };
+                    self.failure(text, &mut diagnostics, &mut last_failure);
+                    remove_directory(directory).await;
+                }
+            }
+        }
+    }
+
+    fn clear_diagnostics(&self, paths: &mut BTreeSet<PathBuf>) {
+        for path in std::mem::take(paths) {
+            self.sink.emit(IdeEvent::Diagnostics { path: path.into(), source: SOURCE.into(), items: Vec::new() });
+        }
+    }
+
+    fn failure(&self, text: String, paths: &mut BTreeSet<PathBuf>, previous: &mut String) {
+        let text = if text.is_empty() { "Kotlin compilation failed".to_owned() } else { text };
+        let text = format!("{text}\nJava temporarily uses the last successfully compiled Kotlin API.");
+        self.clear_diagnostics(paths);
+        let path = self.root.join("pom.xml");
+        paths.insert(path.clone());
+        self.sink.emit(IdeEvent::Diagnostics {
+            path: path.into(),
+            source: SOURCE.into(),
+            items: vec![Diagnostic {
+                range: Range { start: Pos { line: 0, col: 0 }, end: Pos { line: 0, col: 0 } },
+                severity: Severity::Error,
+                message: text.clone(),
+                source: Some(SOURCE.into()),
+                server: Some(SOURCE.into()),
+                code: None,
+                unnecessary: false,
+                deprecated: false,
+            }],
+        });
+        if previous != &text {
+            self.sink.emit(IdeEvent::Notify {
+                level: NotifyLevel::Error,
+                title: "Kotlin editor compilation failed".into(),
+                body: Some(text.clone()),
+            });
+            *previous = text;
+        }
+    }
+}
+
+fn relevant_change(root: &Path, path: &Path, settings: &ide_core::settings::Settings) -> bool {
+    let input = path.extension().is_some_and(|e| e == "kt")
+        || path.file_name().is_some_and(|n| n == "pom.xml" || n == "mvnw" || n == "mvnw.cmd")
+        || path.components().any(|c| c.as_os_str() == ".mvn");
+    let Ok(relative) = path.strip_prefix(root) else {
+        // Content roots outside the project only contribute Kotlin sources.
+        return path.extension().is_some_and(|e| e == "kt");
+    };
+    // Build outputs and generated sources (e.g. KSP's `.kt` under target/) never trigger,
+    // so a build cannot schedule itself.
+    if relative.components().any(|c| {
+        matches!(
+            c.as_os_str().to_str(),
+            Some("target" | "build" | "out" | "bin" | ".git" | "node_modules" | ".openidea")
+        )
+    }) || ide_vfs::ExcludeMatcher::new(&settings.exclude_globs()).is_excluded(relative)
+    {
+        return false;
+    }
+    if input {
+        return true;
+    }
+    if path.extension().is_some() {
+        return false;
+    }
+    // Works for deleted directories too; the module POM remains on disk.
+    path.ancestors().take_while(|ancestor| ancestor.starts_with(root)).any(|ancestor| {
+        ancestor.file_name().is_some_and(|name| name == "src")
+            && ancestor.parent().is_some_and(|module| module.join("pom.xml").is_file())
+    })
+}
+
+async fn debounce(cancel: &CancellationToken, lifetime: &CancellationToken) -> bool {
+    tokio::select! {
+        _ = lifetime.cancelled() => false,
+        _ = cancel.cancelled() => false,
+        _ = tokio::time::sleep(DELAY) => true,
+    }
+}
+
+async fn remove_directory(path: PathBuf) {
+    let _ = tokio::task::spawn_blocking(move || std::fs::remove_dir_all(path)).await;
+}
+
+impl DocumentObserver for KotlinBridge {
+    fn saved(&self, _doc: ide_core::DocId, path: &Path, _text: &str) {
+        self.files_changed(std::iter::once(&path.to_path_buf()));
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn target_package_directory_does_not_trigger() {
+        let dir = tempfile::tempdir().unwrap();
+        std::fs::write(dir.path().join("pom.xml"), "").unwrap();
+        assert!(!relevant_change(dir.path(), &dir.path().join("target/classes/probe"), &Default::default()));
+        let generated = dir.path().join("target/generated-sources/ksp/main/kotlin/Gen.kt");
+        assert!(!relevant_change(dir.path(), &generated, &Default::default()));
+        assert!(relevant_change(dir.path(), &dir.path().join("src/main/kotlin/A.kt"), &Default::default()));
+    }
+
+    #[test]
+    fn deleted_source_package_triggers_unless_excluded() {
+        let dir = tempfile::tempdir().unwrap();
+        std::fs::create_dir_all(dir.path().join("module")).unwrap();
+        std::fs::write(dir.path().join("module/pom.xml"), "").unwrap();
+        let path = dir.path().join("module/src/main/kotlin/pkg");
+        let mut settings = ide_core::settings::Settings::default();
+        assert!(relevant_change(dir.path(), &path, &settings));
+        settings.project_structure.excluded.push("module/src/main/kotlin".into());
+        assert!(!relevant_change(dir.path(), &path, &settings));
+        assert!(!relevant_change(dir.path(), &dir.path().join("module/src/build/pkg"), &Default::default()));
+    }
+
+    #[test]
+    fn extensionless_root_file_does_not_trigger() {
+        let dir = tempfile::tempdir().unwrap();
+        std::fs::write(dir.path().join("pom.xml"), "").unwrap();
+        assert!(!relevant_change(dir.path(), &dir.path().join("LICENSE"), &Default::default()));
+    }
+
+    #[tokio::test(start_paused = true)]
+    async fn burst_saves_cancel_the_pending_debounce() {
+        let mut state = Revision::default();
+        state.change();
+        let token = state.cancel.clone();
+        let lifetime = CancellationToken::new();
+        let pending_lifetime = lifetime.clone();
+        let waiting = tokio::spawn(async move { debounce(&token, &pending_lifetime).await });
+        tokio::task::yield_now().await;
+        tokio::time::advance(DELAY - Duration::from_millis(1)).await;
+        assert!(!waiting.is_finished());
+        for _ in 0..20 {
+            state.change();
+        }
+        assert!(!waiting.await.unwrap());
+        let current = state.generation;
+        assert!(debounce(&state.cancel, &lifetime).await);
+        assert!(state.current(current));
+        lifetime.cancel();
+        assert!(!debounce(&state.cancel, &lifetime).await);
+    }
+
+    #[test]
+    fn superseded_and_cancelled_builds_cannot_publish() {
+        let mut state = Revision::default();
+        state.change();
+        let first = state.generation;
+        let token = state.cancel.clone();
+        state.change();
+        assert!(token.is_cancelled());
+        assert!(!state.current(first));
+        assert!(state.current(state.generation));
+        state.cancel.cancel();
+        assert!(!state.current(state.generation));
+    }
+}
@@ -4,12 +4,17 @@
 //! runs one on a remote machine and serves it over JSON-RPC ([`rpc`]).

 pub mod environment;
+mod formatter;
+mod java_runtime;
+mod kotlin_bridge;
+pub mod notebook;
 pub mod ops;
 mod project;
 mod proxy;
 mod requests;
 pub mod rpc;
 pub mod shell_env;
+pub mod trust;

 pub use project::{Project, apply_git_executable, apply_workspace_edit, history_retention};

@@ -42,6 +47,7 @@ pub struct HostConfig {
 }

 pub struct Host {
+    pub trust: trust::TrustStore,
    pub config_dir: PathBuf,
    pub data_dir: PathBuf,
    pub languages: Arc<LanguageRegistry>,
@@ -65,6 +71,7 @@ pub struct Host {
    /// One project per window, keyed by window label.
    projects: RwLock<HashMap<String, Arc<Project>>>,
    requests: requests::Requests,
+    project_requests: RwLock<HashMap<String, Vec<RequestId>>>,
 }

 impl Host {
@@ -75,6 +82,7 @@ impl Host {
        let ssh = Arc::new(ide_ssh::SshManager::new(data_dir.join("ssh-passwords.json")));
        ssh.set_configs(global_settings.effective().ssh.configs);
        let host = Self {
+            trust: trust::TrustStore::load(&config_dir, &data_dir),
            proxy_password: ide_ssh::secrets::SecretFile::new(data_dir.join("proxy-password.json")),
            remote: Arc::new(ide_remote::RemoteService::new(ssh.clone(), data_dir.join("remote"))),
            ssh,
@@ -93,6 +101,7 @@ impl Host {
            runtime,
            projects: RwLock::default(),
            requests: Default::default(),
+            project_requests: RwLock::default(),
        };
        host.apply_proxy();
        host
@@ -117,6 +126,10 @@ impl Host {
            .ok_or_else(|| IdeError::not_found("no project is open in this window"))
    }

+    pub fn require_trust(&self, window: &str) -> IdeResult<()> {
+        self.project(window)?.require_trust()
+    }
+
    /// The window that owns what `window` starts.
    pub fn owner_window<'a>(&self, window: &'a str) -> &'a str {
        (self.owner)(window)
@@ -132,26 +145,101 @@ impl Host {
    }

    pub fn close_project(&self, window: &str) {
-        if let Some(project) = self.projects.write().remove(window) {
+        let project = self.projects.write().remove(window);
+        if let Some(project) = project {
            if !project.light {
                self.environment.project_closed();
            }
+            if let Some(bridge) = &project.kotlin_bridge {
+                bridge.stop();
+            }
            project.agents.shutdown();
+            project.notebooks.stop_admission();
+            self.shutdown_project_workers_blocking(
+                vec![project.notebooks.clone()],
+                project.kotlin_bridge.iter().cloned().collect(),
+            );
            let lsp = project.lsp.clone();
            self.runtime.spawn(async move { lsp.shutdown_all().await });
        }
    }

-    /// Stops what this host started: language servers, agents, runs and terminals.
+    /// Synchronous project/window destruction must finish owned kernel cleanup,
+    /// not enqueue work which can be lost as the desktop runtime exits.
+    fn shutdown_project_workers_blocking(
+        &self,
+        notebooks: Vec<Arc<notebook::NotebookService>>,
+        bridges: Vec<Arc<kotlin_bridge::KotlinBridge>>,
+    ) {
+        for bridge in &bridges {
+            bridge.stop();
+        }
+        for service in &notebooks {
+            service.stop_admission();
+        }
+        let runtime = self.runtime.clone();
+        let wait = move || {
+            let worker = std::thread::spawn(move || {
+                runtime.block_on(async move {
+                    for bridge in bridges {
+                        bridge.shutdown().await;
+                    }
+                    for service in notebooks {
+                        service.shutdown().await;
+                    }
+                });
+            });
+            if let Err(error) = worker.join() {
+                tracing::error!("notebook shutdown thread failed: {error:?}");
+            }
+        };
+        if tokio::runtime::Handle::try_current()
+            .is_ok_and(|handle| handle.runtime_flavor() == tokio::runtime::RuntimeFlavor::MultiThread)
+        {
+            tokio::task::block_in_place(wait);
+        } else {
+            wait();
+        }
+    }
+
+    /// Called before the desktop runtime exits, including update/restart exits.
+    pub fn shutdown_notebooks_on_exit(&self) {
+        let projects = self.projects();
+        self.shutdown_project_workers_blocking(
+            projects.iter().map(|project| project.notebooks.clone()).collect(),
+            projects.iter().filter_map(|project| project.kotlin_bridge.clone()).collect(),
+        );
+    }
+
+    /// Stops what this host started: notebook kernels, language servers, agents, runs and terminals.
    /// For a process that exits without dropping the host (the remote server).
    pub async fn shutdown(&self) {
        self.environment.shutdown();
        self.processes.kill_all();
        self.terminals.kill_all();
        let projects: Vec<_> = self.projects.write().drain().map(|(_, p)| p).collect();
-        for project in projects {
+        for project in &projects {
+            if let Some(bridge) = &project.kotlin_bridge {
+                bridge.stop();
+            }
+            project.notebooks.stop_admission();
            project.agents.shutdown();
-            project.lsp.shutdown_all().await;
+        }
+        // Kernel cleanup owns its interrupt/termination/reaping deadlines. An
+        // outer LSP timeout must never abort it before owned children are reaped.
+        for project in &projects {
+            if let Some(bridge) = &project.kotlin_bridge {
+                bridge.shutdown().await;
+            }
+            project.notebooks.shutdown().await;
+        }
+        let stop_language_servers = async {
+            for project in &projects {
+                project.lsp.shutdown_all().await;
+            }
+        };
+        if tokio::time::timeout(std::time::Duration::from_secs(10), stop_language_servers).await.is_err() {
+            tracing::warn!("language servers did not shut down in time");
        }
    }

@@ -161,7 +249,19 @@ impl Host {
        self.requests.begin(id)
    }

+    pub fn begin_project_request(&self, window: &str, id: RequestId) -> CancellationToken {
+        let token = self.begin_request(id);
+        self.project_requests.write().entry(self.owner_window(window).to_owned()).or_default().push(id);
+        if self.project(window).is_ok_and(|p| !p.is_trusted()) {
+            token.cancel();
+        }
+        token
+    }
+
    pub fn end_request(&self, id: RequestId) {
+        for ids in self.project_requests.write().values_mut() {
+            ids.retain(|entry| *entry != id);
+        }
        self.requests.end(id);
    }

@@ -0,0 +1,814 @@
+//! Project-incarnation notebook ownership and whole-batch execution admission.
+use crate::ops::Channel;
+use ide_core::error::ErrorKind;
+use ide_core::{CancellationToken, IdeError, IdeEvent, IdeResult, SharedSink};
+use ide_notebook::kernel::{KernelManager, KernelOutput};
+use ide_notebook::{NotebookDocument, NotebookEdit, NotebookSnapshot};
+use parking_lot::Mutex;
+use serde::Serialize;
+use specta::Type;
+use std::collections::{HashMap, HashSet};
+use std::path::{Path, PathBuf};
+use std::sync::Arc;
+use std::time::Duration;
+use tokio::sync::{Mutex as AsyncMutex, watch};
+
+#[derive(Clone, Debug, Serialize, Type)]
+#[serde(rename_all = "camelCase")]
+pub struct NotebookOutputEvent {
+    pub id: String,
+    pub path: String,
+    pub cell: String,
+    pub msg_id: String,
+    pub kind: String,
+    #[specta(type = specta_typescript::Unknown)]
+    pub content: serde_json::Value,
+    pub version: u32,
+    pub dirty: bool,
+    pub changed_cells: Vec<String>,
+}
+
+#[derive(Default)]
+struct Registry {
+    stopped: bool,
+    paths: HashMap<PathBuf, String>,
+    documents: HashMap<String, Arc<ManagedDocument>>,
+}
+
+struct ManagedDocument {
+    id: String,
+    path: PathBuf,
+    state: Mutex<DocumentState>,
+    control: AsyncMutex<()>,
+}
+
+struct DocumentState {
+    document: NotebookDocument,
+    generation: u64,
+    transitioning: bool,
+    closed: bool,
+    active: Option<Arc<Batch>>,
+    kernel_status: Option<(String, Option<String>)>,
+}
+
+struct Batch {
+    cancel: CancellationToken,
+    done: watch::Sender<bool>,
+}
+
+struct BatchGuard {
+    document: Arc<ManagedDocument>,
+    batch: Arc<Batch>,
+}
+
+pub(crate) struct ExecutionAdmission {
+    guard: BatchGuard,
+    generation: u64,
+    plan: Vec<(String, String)>,
+}
+
+impl Drop for BatchGuard {
+    fn drop(&mut self) {
+        let mut state = self.document.state.lock();
+        if state.active.as_ref().is_some_and(|active| Arc::ptr_eq(active, &self.batch)) {
+            if let Err(error) = state.document.set_execution_active(false) {
+                tracing::error!("notebook batch release: {error}");
+            }
+            state.active = None;
+        }
+        self.batch.done.send_replace(true);
+    }
+}
+
+pub struct NotebookService {
+    registry: Arc<Mutex<Registry>>,
+    kernels: Arc<KernelManager>,
+    sink: SharedSink,
+}
+
+impl NotebookService {
+    pub fn new(runtime_dir: PathBuf, sink: SharedSink) -> Arc<Self> {
+        let registry = Arc::new(Mutex::new(Registry::default()));
+        let status_registry = registry.clone();
+        let status_sink = sink.clone();
+        let kernels = KernelManager::new(
+            runtime_dir,
+            Arc::new(move |path, status, message| {
+                let document = {
+                    let registry = status_registry.lock();
+                    if registry.stopped {
+                        return;
+                    }
+                    registry.paths.get(path).and_then(|id| registry.documents.get(id)).cloned()
+                };
+                if let Some(document) = document {
+                    let deliver = {
+                        let mut state = document.state.lock();
+                        if state.closed {
+                            return;
+                        }
+                        state.kernel_status = Some((status.as_str().to_owned(), message.clone()));
+                        !state.transitioning
+                    };
+                    if deliver {
+                        status_sink.emit(IdeEvent::NotebookKernel {
+                            id: document.id.clone(),
+                            path: path.to_path_buf().into(),
+                            state: status.as_str().to_owned(),
+                            message,
+                        });
+                    }
+                }
+            }),
+        );
+        Arc::new(Self { registry, kernels: Arc::new(kernels), sink })
+    }
+
+    pub fn open(&self, path: &Path) -> IdeResult<NotebookSnapshot> {
+        let path = dunce::canonicalize(path)?;
+        // Serialize first load with path insertion: split views share one incarnation.
+        let mut registry = self.registry.lock();
+        if registry.stopped {
+            return Err(IdeError::cancelled());
+        }
+        if let Some(id) = registry.paths.get(&path) {
+            return snapshot(&registry.documents[id]);
+        }
+        let document = NotebookDocument::load(&path)?;
+        let initial = document.snapshot();
+        let id = initial.id.clone();
+        registry.paths.insert(path.clone(), id.clone());
+        registry.documents.insert(
+            id.clone(),
+            Arc::new(ManagedDocument {
+                id,
+                path,
+                state: Mutex::new(DocumentState {
+                    document,
+                    generation: 0,
+                    transitioning: false,
+                    closed: false,
+                    active: None,
+                    kernel_status: None,
+                }),
+                control: AsyncMutex::new(()),
+            }),
+        );
+        Ok(initial)
+    }
+
+    fn resolve(&self, id: &str) -> IdeResult<Arc<ManagedDocument>> {
+        let registry = self.registry.lock();
+        if registry.stopped {
+            return Err(IdeError::not_found("notebook project has closed"));
+        }
+        registry.documents.get(id).cloned().ok_or_else(|| IdeError::not_found("notebook incarnation is closed"))
+    }
+
+    pub fn get(&self, id: &str) -> IdeResult<NotebookSnapshot> {
+        snapshot(self.resolve(id)?.as_ref())
+    }
+
+    pub fn edit(&self, id: &str, version: u32, edit: NotebookEdit) -> IdeResult<NotebookSnapshot> {
+        let document = self.resolve(id)?;
+        let mut state = document.state.lock();
+        mutable(&state)?;
+        state.document.edit(version, edit)
+    }
+
+    pub fn save(&self, id: &str) -> IdeResult<NotebookSnapshot> {
+        let document = self.resolve(id)?;
+        let mut state = document.state.lock();
+        mutable(&state)?;
+        state.document.save()
+    }
+
+    pub fn undo(&self, id: &str, redo: bool) -> IdeResult<NotebookSnapshot> {
+        let document = self.resolve(id)?;
+        let mut state = document.state.lock();
+        mutable(&state)?;
+        if state.active.is_some() {
+            return Err(IdeError::unavailable("stop notebook execution before undo or redo"));
+        }
+        if redo { state.document.redo() } else { state.document.undo() }
+    }
+
+    pub async fn interrupt(&self, id: &str) -> IdeResult<()> {
+        let document = self.resolve(id)?;
+        let batch = document.state.lock().active.clone();
+        if let Some(batch) = &batch {
+            batch.cancel.cancel();
+        }
+        // Draining makes prepareClose/save a stable checkpoint, including when
+        // Python catches KeyboardInterrupt or cancel races with kernel startup.
+        let interrupt = self.kernels.interrupt(&document.path).await;
+        self.drain(&document, batch).await?;
+        interrupt
+    }
+
+    async fn drain(&self, document: &ManagedDocument, batch: Option<Arc<Batch>>) -> IdeResult<()> {
+        let Some(batch) = batch else { return Ok(()) };
+        let mut done = batch.done.subscribe();
+        match tokio::time::timeout(Duration::from_secs(5), done.wait_for(|done| *done)).await {
+            Ok(Ok(_)) => return Ok(()),
+            Ok(Err(_)) => return Err(IdeError::internal("notebook execution completion channel closed")),
+            Err(_) => {}
+        }
+        // An uncooperative kernel must not outlive a close/reload authorization.
+        self.kernels.shutdown_kernel(&document.path).await?;
+        tokio::time::timeout(Duration::from_secs(5), done.wait_for(|done| *done))
+            .await
+            .map_err(|_| IdeError::unavailable("notebook execution did not stop after kernel shutdown"))?
+            .map_err(|_| IdeError::internal("notebook execution completion channel closed"))?;
+        Ok(())
+    }
+
+    pub async fn reload(&self, id: &str, restart: bool) -> IdeResult<NotebookSnapshot> {
+        let document = self.resolve(id)?;
+        let _control = document.control.lock().await;
+        let batch = invalidate(&document)?;
+        let result = async {
+            let _ = self.kernels.interrupt(&document.path).await;
+            self.drain(&document, batch).await?;
+            if document.state.lock().closed {
+                return Err(IdeError::cancelled());
+            }
+            if restart {
+                self.kernels.restart(&document.path).await?;
+                snapshot(&document)
+            } else {
+                self.kernels.shutdown_kernel(&document.path).await?;
+                document.state.lock().document.reload()
+            }
+        }
+        .await;
+        let status = {
+            let mut state = document.state.lock();
+            state.transitioning = false;
+            if state.closed { None } else { state.kernel_status.clone() }
+        };
+        if let Some((state, message)) = status {
+            self.sink.emit(IdeEvent::NotebookKernel {
+                id: document.id.clone(),
+                path: document.path.clone().into(),
+                state,
+                message,
+            });
+        }
+        result
+    }
+
+    /// Frontend disposal may arrive after project replacement has already retired this id.
+    pub async fn close(&self, id: &str) -> IdeResult<()> {
+        let document = match self.resolve(id) {
+            Ok(document) => document,
+            Err(error) if error.kind == ErrorKind::NotFound => return Ok(()),
+            Err(error) => return Err(error),
+        };
+        let _control = document.control.lock().await;
+        if document.state.lock().closed {
+            return Ok(());
+        }
+        let batch = invalidate(&document)?;
+        let result = async {
+            let _ = self.kernels.interrupt(&document.path).await;
+            self.drain(&document, batch).await?;
+            self.kernels.shutdown_kernel(&document.path).await
+        }
+        .await;
+        if let Err(error) = result {
+            document.state.lock().transitioning = false;
+            return Err(error);
+        }
+        document.state.lock().closed = true;
+        let mut registry = self.registry.lock();
+        registry.documents.remove(id);
+        registry.paths.remove(&document.path);
+        Ok(())
+    }
+
+    pub(crate) fn admit(
+        &self,
+        id: &str,
+        cells: Vec<String>,
+        cancel: CancellationToken,
+    ) -> IdeResult<ExecutionAdmission> {
+        admit(self.resolve(id)?, cells, cancel)
+    }
+
+    pub(crate) async fn execute(
+        self: &Arc<Self>,
+        admission: ExecutionAdmission,
+        python: PathBuf,
+        on_output: Channel<NotebookOutputEvent>,
+    ) -> IdeResult<NotebookSnapshot> {
+        let document = admission.guard.document.clone();
+        let service = self.clone();
+        // Keep admission and native execution owned if an IPC receiver disappears.
+        tokio::spawn(async move {
+            let ExecutionAdmission { guard, generation, plan } = admission;
+            let result =
+                service.run_batch(document.clone(), generation, plan, python, guard.batch.clone(), on_output).await;
+            drop(guard);
+            match result {
+                Ok(()) => snapshot(&document),
+                Err(error) => Err(error),
+            }
+        })
+        .await
+        .map_err(|error| IdeError::internal(error.to_string()))?
+    }
+
+    async fn run_batch(
+        &self,
+        document: Arc<ManagedDocument>,
+        generation: u64,
+        plan: Vec<(String, String)>,
+        python: PathBuf,
+        batch: Arc<Batch>,
+        on_output: Channel<NotebookOutputEvent>,
+    ) -> IdeResult<()> {
+        for (cell, source) in plan {
+            {
+                let mut state = document.state.lock();
+                if batch.cancel.is_cancelled() || state.closed || state.generation != generation {
+                    return Err(IdeError::cancelled());
+                }
+                // A user may delete a queued cell while an earlier one executes.
+                // Never resurrect it from the captured source or a late output.
+                match state.document.begin_execution(&cell) {
+                    Ok(()) => {}
+                    Err(error) if error.kind == ErrorKind::NotFound => continue,
+                    Err(error) => return Err(error),
+                }
+            }
+            let output_error = Arc::new(Mutex::new(None));
+            let callback_document = document.clone();
+            let callback_batch = batch.clone();
+            let callback_error = output_error.clone();
+            let callback_cell = cell.clone();
+            let channel = on_output.clone();
+            let result = self
+                .kernels
+                .execute(
+                    &document.path,
+                    &python,
+                    &source,
+                    batch.cancel.clone(),
+                    Arc::new(move |output: KernelOutput| {
+                        let event = match commit_output(
+                            &callback_document,
+                            &callback_batch,
+                            generation,
+                            &callback_cell,
+                            output,
+                        ) {
+                            Ok(Some(event)) => event,
+                            Ok(None) => return,
+                            Err(error) => {
+                                *callback_error.lock() = Some(error);
+                                callback_batch.cancel.cancel();
+                                return;
+                            }
+                        };
+                        let _ = channel.send(event);
+                    }),
+                )
+                .await;
+            if let Some(error) = output_error.lock().take() {
+                return Err(error);
+            }
+            let result = result?;
+            if batch.cancel.is_cancelled() {
+                return Err(IdeError::cancelled());
+            }
+            if result.status != "ok" {
+                break;
+            }
+        }
+        let state = document.state.lock();
+        if state.closed || state.generation != generation || batch.cancel.is_cancelled() {
+            return Err(IdeError::cancelled());
+        }
+        Ok(())
+    }
+
+    /// Synchronously revoke admission before handing cleanup to an async runtime.
+    pub fn stop_admission(&self) {
+        let mut registry = self.registry.lock();
+        registry.stopped = true;
+        for document in registry.documents.values() {
+            let mut state = document.state.lock();
+            state.closed = true;
+            state.generation += 1;
+            if let Some(batch) = &state.active {
+                batch.cancel.cancel();
+            }
+        }
+    }
+
+    pub async fn restrict(&self) {
+        let documents: Vec<_> = self.registry.lock().documents.values().cloned().collect();
+        for document in &documents {
+            let mut state = document.state.lock();
+            state.generation += 1;
+            if let Some(batch) = &state.active {
+                batch.cancel.cancel();
+            }
+        }
+        for document in documents {
+            let _ = self.kernels.shutdown_kernel(&document.path).await;
+            let batch = document.state.lock().active.clone();
+            if let Err(error) = self.drain(&document, batch).await {
+                tracing::warn!("notebook restriction: {error}");
+            }
+        }
+    }
+
+    pub async fn shutdown(&self) {
+        self.stop_admission();
+        self.kernels.shutdown().await;
+        let documents: Vec<_> = self.registry.lock().documents.values().cloned().collect();
+        for document in documents {
+            let batch = document.state.lock().active.clone();
+            if let Err(error) = self.drain(&document, batch).await {
+                tracing::error!("notebook cleanup: {error}");
+            }
+        }
+        let mut registry = self.registry.lock();
+        registry.paths.clear();
+        registry.documents.clear();
+    }
+}
+
+fn mutable(state: &DocumentState) -> IdeResult<()> {
+    if state.closed {
+        Err(IdeError::not_found("notebook incarnation is closed"))
+    } else if state.transitioning {
+        Err(IdeError::unavailable("notebook lifecycle operation is in progress"))
+    } else {
+        Ok(())
+    }
+}
+
+fn snapshot(document: &ManagedDocument) -> IdeResult<NotebookSnapshot> {
+    let state = document.state.lock();
+    if state.closed {
+        return Err(IdeError::not_found("notebook incarnation is closed"));
+    }
+    Ok(state.document.snapshot())
+}
+
+fn invalidate(document: &ManagedDocument) -> IdeResult<Option<Arc<Batch>>> {
+    let mut state = document.state.lock();
+    mutable(&state)?;
+    state.transitioning = true;
+    state.generation += 1;
+    if let Some(batch) = &state.active {
+        batch.cancel.cancel();
+    }
+    Ok(state.active.clone())
+}
+
+fn execution_plan(snapshot: &NotebookSnapshot, cells: Vec<String>) -> IdeResult<Vec<(String, String)>> {
+    let mut selected: HashSet<_> = cells.iter().map(String::as_str).collect();
+    if selected.is_empty() || selected.len() != cells.len() {
+        return Err(IdeError::invalid("select distinct code cells to execute"));
+    }
+    let mut plan = Vec::with_capacity(selected.len());
+    for cell in &snapshot.cells {
+        if selected.remove(cell.id.as_str()) {
+            if cell.cell_type != "code" {
+                return Err(IdeError::invalid("only code cells can execute"));
+            }
+            plan.push((cell.id.clone(), cell.source.clone()));
+        }
+    }
+    if !selected.is_empty() {
+        return Err(IdeError::not_found("an execution cell no longer exists"));
+    }
+    Ok(plan)
+}
+
+fn admit(
+    document: Arc<ManagedDocument>,
+    cells: Vec<String>,
+    cancel: CancellationToken,
+) -> IdeResult<ExecutionAdmission> {
+    let (batch, generation, plan) = {
+        let mut state = document.state.lock();
+        mutable(&state)?;
+        if state.active.is_some() {
+            return Err(IdeError::unavailable("notebook execution batch is already running"));
+        }
+        if cancel.is_cancelled() {
+            return Err(IdeError::cancelled());
+        }
+        let plan = execution_plan(&state.document.snapshot(), cells)?;
+        state.document.set_execution_active(true)?;
+        let (done, _) = watch::channel(false);
+        let batch = Arc::new(Batch { cancel, done });
+        state.active = Some(batch.clone());
+        (batch, state.generation, plan)
+    };
+    Ok(ExecutionAdmission { guard: BatchGuard { document, batch }, generation, plan })
+}
+
+/// Commit under the short document lock; the caller delivers only after release.
+fn commit_output(
+    document: &ManagedDocument,
+    batch: &Arc<Batch>,
+    generation: u64,
+    cell: &str,
+    output: KernelOutput,
+) -> IdeResult<Option<NotebookOutputEvent>> {
+    let mut state = document.state.lock();
+    if state.closed
+        || state.generation != generation
+        || !state.active.as_ref().is_some_and(|active| Arc::ptr_eq(active, batch))
+    {
+        return Ok(None);
+    }
+    let changed_cells = match state.document.record_output(cell, &output) {
+        Ok(changed) => changed,
+        Err(error) if error.kind == ErrorKind::NotFound => return Ok(None),
+        Err(error) => return Err(error),
+    };
+    Ok(Some(NotebookOutputEvent {
+        id: document.id.clone(),
+        path: document.path.to_string_lossy().into_owned(),
+        cell: cell.to_owned(),
+        msg_id: output.msg_id,
+        kind: output.kind,
+        content: output.content,
+        version: state.document.version(),
+        dirty: state.document.is_dirty(),
+        changed_cells,
+    }))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use serde_json::json;
+
+    fn fixture() -> (tempfile::TempDir, Arc<NotebookService>, NotebookSnapshot) {
+        let dir = tempfile::tempdir().unwrap();
+        let path = dir.path().join("session.ipynb");
+        std::fs::write(&path, serde_json::to_vec(&json!({
+            "nbformat": 4, "nbformat_minor": 5, "metadata": {},
+            "cells": [
+                {"id":"first","cell_type":"code","metadata":{},"source":"x = 1","outputs":[],"execution_count":null},
+                {"id":"second","cell_type":"code","metadata":{},"source":"print(x)","outputs":[],"execution_count":null},
+                {"id":"prose","cell_type":"markdown","metadata":{},"source":"notes"}
+            ]
+        })).unwrap()).unwrap();
+        let service = NotebookService::new(dir.path().join("kernels"), Arc::new(ide_core::NullSink));
+        let snapshot = service.open(&path).unwrap();
+        (dir, service, snapshot)
+    }
+
+    fn output(kind: &str, content: serde_json::Value) -> KernelOutput {
+        KernelOutput { kind: kind.into(), content, msg_id: "actual-parent-request".into() }
+    }
+
+    #[tokio::test]
+    async fn canonical_split_opens_share_incarnation_but_reopen_and_projects_do_not() {
+        let (dir, service, initial) = fixture();
+        let alternate = dir.path().join(".").join("session.ipynb");
+        assert_eq!(service.open(&alternate).unwrap().id, initial.id);
+        let other = NotebookService::new(dir.path().join("other-runtime"), Arc::new(ide_core::NullSink));
+        let independent = other.open(&alternate).unwrap();
+        assert_ne!(initial.id, independent.id);
+        assert_eq!(other.get(&initial.id).unwrap_err().kind, ErrorKind::NotFound);
+        service.close(&initial.id).await.unwrap();
+        let reopened = service.open(&alternate).unwrap();
+        assert_ne!(reopened.id, initial.id);
+        assert_eq!(service.get(&initial.id).unwrap_err().kind, ErrorKind::NotFound);
+        // A delayed old-incarnation close cannot dispose a new session at that path.
+        service.close(&initial.id).await.unwrap();
+        assert_eq!(service.get(&reopened.id).unwrap().id, reopened.id);
+        service.shutdown().await;
+        other.shutdown().await;
+    }
+
+    #[tokio::test(start_paused = true)]
+    async fn failed_close_keeps_the_incarnation_recoverable_until_a_retry_succeeds() {
+        let (dir, service, initial) = fixture();
+        // A batch that never drains models a kernel that ignores interrupt and shutdown.
+        let admission =
+            service.admit(&initial.id, vec![initial.cells[0].id.clone()], CancellationToken::new()).unwrap();
+        let error = service.close(&initial.id).await.unwrap_err();
+        assert_eq!(error.kind, ErrorKind::Unavailable);
+        assert!(admission.guard.batch.cancel.is_cancelled());
+        // The backend still owns the incarnation: a reopen shares it instead of
+        // starting a second kernel, and the failed close left it usable.
+        let reopened = service.open(&dir.path().join("session.ipynb")).unwrap();
+        assert_eq!(reopened.id, initial.id);
+        assert!(matches!(service.admit(&initial.id, vec![initial.cells[0].id.clone()], CancellationToken::new()),
+            Err(error) if error.kind == ErrorKind::Unavailable));
+        drop(admission);
+        service.close(&initial.id).await.unwrap();
+        assert_eq!(service.get(&initial.id).unwrap_err().kind, ErrorKind::NotFound);
+        assert_ne!(service.open(&dir.path().join("session.ipynb")).unwrap().id, initial.id);
+        service.shutdown().await;
+    }
+
+    #[test]
+    fn batch_admission_captures_document_order_and_retains_busy_until_drained() {
+        let (_dir, service, initial) = fixture();
+        let document = service.resolve(&initial.id).unwrap();
+        let cells = vec![initial.cells[1].id.clone(), initial.cells[0].id.clone()];
+        let admission = admit(document.clone(), cells.clone(), CancellationToken::new()).unwrap();
+        assert_eq!(
+            admission.plan,
+            vec![(initial.cells[0].id.clone(), "x = 1".into()), (initial.cells[1].id.clone(), "print(x)".into()),]
+        );
+        service
+            .edit(
+                &initial.id,
+                initial.version,
+                NotebookEdit::SetSource { cell: initial.cells[1].id.clone(), source: "print('new source')".into() },
+            )
+            .unwrap();
+        assert_eq!(admission.plan[1].1, "print(x)");
+        assert_eq!(service.undo(&initial.id, false).unwrap_err().kind, ErrorKind::Unavailable);
+        admission.guard.batch.cancel.cancel();
+        assert!(matches!(admit(document.clone(), cells.clone(), CancellationToken::new()), Err(error)
+            if error.kind == ErrorKind::Unavailable));
+        drop(admission);
+        let next = admit(document, cells, CancellationToken::new()).unwrap();
+        assert_eq!(next.plan[1].1, "print('new source')");
+    }
+
+    #[test]
+    fn output_commits_revision_and_cross_cell_display_updates_before_delivery() {
+        let (_dir, service, initial) = fixture();
+        let document = service.resolve(&initial.id).unwrap();
+        let cells: Vec<_> = initial.cells[..2].iter().map(|cell| cell.id.clone()).collect();
+        let admission = admit(document.clone(), cells.clone(), CancellationToken::new()).unwrap();
+        let event = commit_output(
+            &document,
+            &admission.guard.batch,
+            admission.generation,
+            &cells[0],
+            output(
+                "display_data",
+                json!({"data":{"text/plain":"before"},"metadata":{},"transient":{"display_id":"shared"}}),
+            ),
+        )
+        .unwrap()
+        .unwrap();
+        let committed = service.get(&initial.id).unwrap();
+        assert_eq!(event.version, committed.version);
+        assert!(event.version > initial.version);
+        assert!(event.dirty);
+        assert_eq!(event.msg_id, "actual-parent-request");
+        assert_eq!(committed.cells[0].outputs[0]["data"]["text/plain"], "before");
+        let updated = commit_output(
+            &document,
+            &admission.guard.batch,
+            admission.generation,
+            &cells[1],
+            output(
+                "update_display_data",
+                json!({"data":{"text/plain":"after"},"metadata":{},"transient":{"display_id":"shared"}}),
+            ),
+        )
+        .unwrap()
+        .unwrap();
+        assert!(updated.changed_cells.contains(&cells[0]));
+        let committed = service.get(&initial.id).unwrap();
+        assert_eq!(committed.cells[0].outputs[0]["data"]["text/plain"], "after");
+        assert!(committed.cells[0].outputs[0].get("transient").is_none());
+        assert_eq!(updated.version, committed.version);
+    }
+
+    #[test]
+    fn invalidated_or_completed_batches_cannot_commit_and_deleted_cells_stay_deleted() {
+        let (_dir, service, initial) = fixture();
+        let document = service.resolve(&initial.id).unwrap();
+        let cell = initial.cells[0].id.clone();
+        let admission = admit(document.clone(), vec![cell.clone()], CancellationToken::new()).unwrap();
+        let deleted =
+            service.edit(&initial.id, initial.version, NotebookEdit::DeleteCell { cell: cell.clone() }).unwrap();
+        assert!(
+            commit_output(
+                &document,
+                &admission.guard.batch,
+                admission.generation,
+                &cell,
+                output("stream", json!({"name":"stdout","text":"late"}))
+            )
+            .unwrap()
+            .is_none()
+        );
+        assert_eq!(service.get(&initial.id).unwrap().version, deleted.version);
+        let other = initial.cells[1].id.clone();
+        invalidate(&document).unwrap();
+        assert!(admission.guard.batch.cancel.is_cancelled());
+        assert!(
+            commit_output(
+                &document,
+                &admission.guard.batch,
+                admission.generation,
+                &other,
+                output("stream", json!({"name":"stdout","text":"old generation"}))
+            )
+            .unwrap()
+            .is_none()
+        );
+        let batch = admission.guard.batch.clone();
+        let generation = document.state.lock().generation;
+        drop(admission);
+        assert!(
+            commit_output(
+                &document,
+                &batch,
+                generation,
+                &other,
+                output("stream", json!({"name":"stdout","text":"post idle"}))
+            )
+            .unwrap()
+            .is_none()
+        );
+        assert_eq!(service.get(&initial.id).unwrap().version, deleted.version);
+    }
+
+    #[tokio::test]
+    async fn reload_preserves_incarnation_and_project_shutdown_revokes_all_admission() {
+        let (_dir, service, initial) = fixture();
+        let changed = service
+            .edit(
+                &initial.id,
+                initial.version,
+                NotebookEdit::SetSource { cell: initial.cells[0].id.clone(), source: "changed".into() },
+            )
+            .unwrap();
+        let reloaded = service.reload(&initial.id, false).await.unwrap();
+        assert_eq!(reloaded.id, initial.id);
+        assert!(reloaded.version > changed.version);
+        assert_eq!(reloaded.cells[0].source, "x = 1");
+        assert!(!reloaded.dirty);
+        let document = service.resolve(&initial.id).unwrap();
+        let admission = admit(document.clone(), vec![initial.cells[0].id.clone()], CancellationToken::new()).unwrap();
+        service.stop_admission();
+        assert!(admission.guard.batch.cancel.is_cancelled());
+        assert_eq!(service.get(&initial.id).unwrap_err().kind, ErrorKind::NotFound);
+        assert!(matches!(admit(document, vec![initial.cells[0].id.clone()], CancellationToken::new()), Err(error)
+            if error.kind == ErrorKind::NotFound));
+        drop(admission);
+        service.shutdown().await;
+    }
+
+    #[test]
+    fn invalid_batch_selection_does_not_claim_admission() {
+        let (_dir, service, initial) = fixture();
+        let document = service.resolve(&initial.id).unwrap();
+        for cells in [
+            vec![],
+            vec![initial.cells[0].id.clone(), initial.cells[0].id.clone()],
+            vec![initial.cells[2].id.clone()],
+            vec!["deleted".into()],
+        ] {
+            assert!(admit(document.clone(), cells, CancellationToken::new()).is_err());
+        }
+        let cancelled = CancellationToken::new();
+        cancelled.cancel();
+        assert!(matches!(admit(document.clone(), vec![initial.cells[0].id.clone()], cancelled), Err(error)
+            if error.kind == ErrorKind::Cancelled));
+        let valid = admit(document, vec![initial.cells[0].id.clone()], CancellationToken::new()).unwrap();
+        assert_eq!(valid.plan[0].1, "x = 1");
+    }
+
+    #[tokio::test]
+    async fn interrupt_cancels_before_drain_and_does_not_release_a_live_batch() {
+        let (_dir, service, initial) = fixture();
+        service
+            .edit(
+                &initial.id,
+                initial.version,
+                NotebookEdit::SetSource { cell: initial.cells[0].id.clone(), source: "changed source".into() },
+            )
+            .unwrap();
+        let cancel = CancellationToken::new();
+        let admission = service.admit(&initial.id, vec![initial.cells[0].id.clone()], cancel.clone()).unwrap();
+        let interrupt_service = service.clone();
+        let id = initial.id.clone();
+        let interrupt = tokio::spawn(async move { interrupt_service.interrupt(&id).await });
+        tokio::time::timeout(Duration::from_secs(1), cancel.cancelled()).await.unwrap();
+        assert!(!interrupt.is_finished(), "interrupt must wait for owned execution to drain");
+        assert!(matches!(service.admit(&initial.id, vec![initial.cells[0].id.clone()], CancellationToken::new()),
+            Err(error) if error.kind == ErrorKind::Unavailable));
+        let mut done = admission.guard.batch.done.subscribe();
+        drop(admission);
+        assert!(*done.borrow_and_update());
+        tokio::time::timeout(Duration::from_secs(1), interrupt).await.unwrap().unwrap().unwrap();
+        let next = service.admit(&initial.id, vec![initial.cells[0].id.clone()], CancellationToken::new()).unwrap();
+        assert_eq!(next.plan[0].1, "changed source");
+        drop(next);
+        let undone = service.undo(&initial.id, false).unwrap();
+        assert_eq!(undone.cells[0].source, "x = 1");
+        service.close(&initial.id).await.unwrap();
+    }
+}
@@ -17,6 +17,7 @@ pub fn subscribe(host: &Host, window: &str, on_event: Emit<AgentEvent>) -> IdeRe
 }

 pub fn providers(host: &Host, window: &str) -> IdeResult<Vec<AgentProvider>> {
+    host.require_trust(window)?;
    let mut providers = host.project(window)?.agents.providers();
    ide_agent::registry::mark_updates(&registry_paths(host), &mut providers);
    Ok(providers)
@@ -87,12 +88,20 @@ pub fn entries(host: &Host, window: &str, task: String, subagent: Option<String>
    host.project(window)?.agents.entries(&task, subagent)
 }

-pub async fn create(host: &Host, window: &str, request: NewAgentTask) -> IdeResult<AgentTask> {
-    host.project(window)?.agents.create(request).await
+pub async fn create(host: &Host, window: &str, mut request: NewAgentTask) -> IdeResult<AgentTask> {
+    host.require_trust(window)?;
+    let project = host.project(window)?;
+    let root = project.root.clone();
+    let requested = request.project_root.take();
+    request.project_root = Some(IpcPath(
+        host.blocking(move || validate_project_root(&root, requested.as_ref().map(|p| p.0.as_path()))).await?,
+    ));
+    project.agents.create(request).await
 }

 /// Sends a message; while the agent works it is queued, or with `now` it interrupts the turn.
 pub async fn prompt(host: &Host, window: &str, task: String, prompt: AgentPrompt, now: bool) -> IdeResult<()> {
+    host.require_trust(window)?;
    host.project(window)?.agents.prompt(&task, prompt, now).await
 }

@@ -103,26 +112,31 @@ pub fn unqueue(host: &Host, window: &str, task: String, queued: String) -> IdeRe

 /// Sends a queued message now, interrupting the current turn.
 pub fn send_queued_now(host: &Host, window: &str, task: String, queued: String) -> IdeResult<()> {
+    host.require_trust(window)?;
    host.project(window)?.agents.send_queued_now(&task, &queued)
 }

 /// Changes a session setting (model, mode, thinking effort…).
 pub async fn set_config(host: &Host, window: &str, task: String, option: String, value: String) -> IdeResult<()> {
+    host.require_trust(window)?;
    host.project(window)?.agents.set_config(&task, &option, value).await
 }

 /// Copies the task's conversation into a new task, up to its first `turns` turns (all when `None`).
 pub async fn fork(host: &Host, window: &str, task: String, turns: Option<u32>) -> IdeResult<AgentTask> {
+    host.require_trust(window)?;
    host.project(window)?.agents.fork(&task, turns).await
 }

 /// Drops the task's turns after its first `turns`; returns the message of the first dropped one.
 pub async fn rollback(host: &Host, window: &str, task: String, turns: u32) -> IdeResult<Option<AgentPrompt>> {
+    host.require_trust(window)?;
    host.project(window)?.agents.rollback(&task, turns).await
 }

 /// What the agent reports about itself when it starts, without opening a session.
 pub async fn probe(host: &Host, window: &str, provider: String, refresh: bool) -> IdeResult<AgentProbe> {
+    host.require_trust(window)?;
    host.project(window)?.agents.probe(&provider, refresh).await
 }

@@ -133,6 +147,7 @@ pub fn cancel(host: &Host, window: &str, task: String, subagent: Option<String>)

 /// Answers a permission request; `option: None` cancels it.
 pub fn respond(host: &Host, window: &str, task: String, permission: u32, option: Option<String>) -> IdeResult<()> {
+    host.require_trust(window)?;
    host.project(window)?.agents.respond(&task, permission, option)
 }

@@ -140,16 +155,23 @@ pub fn archive(host: &Host, window: &str, task: String) -> IdeResult<()> {
    host.project(window)?.agents.archive(&task)
 }

+pub fn unarchive(host: &Host, window: &str, task: String) -> IdeResult<()> {
+    host.project(window)?.agents.unarchive(&task)
+}
+
 pub async fn delete(host: &Host, window: &str, task: String, remove_worktree: bool) -> IdeResult<()> {
+    host.require_trust(window)?;
    host.project(window)?.agents.delete(&task, remove_worktree).await
 }

 pub async fn changes(host: &Host, window: &str, task: String) -> IdeResult<Vec<AgentChange>> {
+    host.require_trust(window)?;
    host.project(window)?.agents.changes(&task).await
 }

 /// Content of `path` when the task started (left side of its diff).
 pub async fn base_text(host: &Host, window: &str, task: String, path: IpcPath) -> IdeResult<Option<String>> {
+    host.require_trust(window)?;
    host.project(window)?.agents.base_text(&task, path.into_path_buf()).await
 }

@@ -183,6 +205,7 @@ pub(crate) fn register(d: &mut Dispatcher) {
    d.add("agent_respond", |c| async move {
        respond(&c.host, &c.window, c.arg("task")?, c.arg("permission")?, c.arg("option")?)
    });
+    d.add("agent_unarchive", |c| async move { unarchive(&c.host, &c.window, c.arg("task")?) });
    d.add("agent_archive", |c| async move { archive(&c.host, &c.window, c.arg("task")?) });
    d.add(
        "agent_delete",
@@ -191,3 +214,43 @@ pub(crate) fn register(d: &mut Dispatcher) {
    d.add("agent_changes", |c| async move { changes(&c.host, &c.window, c.arg("task")?).await });
    d.add("agent_base_text", |c| async move { base_text(&c.host, &c.window, c.arg("task")?, c.arg("path")?).await });
 }
+
+fn validate_project_root(root: &std::path::Path, requested: Option<&std::path::Path>) -> IdeResult<std::path::PathBuf> {
+    let Some(requested) = requested else {
+        return Ok(root.to_path_buf());
+    };
+    if !requested.is_absolute() {
+        return Err(IdeError::invalid("Choose an absolute project root"));
+    }
+    let requested = dunce::canonicalize(requested)?;
+    let window_root = dunce::canonicalize(root)?;
+    if requested == window_root
+        || ide_workspace::workspace::Workspace::load(root)?.is_some_and(|w| w.projects.contains(&requested))
+    {
+        return Ok(requested);
+    }
+    Err(IdeError::invalid("Agent project must be the window project or a workspace member"))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn agent_roots_are_exact_window_or_workspace_members() {
+        let tmp = tempfile::tempdir().unwrap();
+        let root = tmp.path().join("workspace");
+        let member = tmp.path().join("member");
+        let other = tmp.path().join("other");
+        for dir in [&root, &member, &other, &member.join("child")] {
+            std::fs::create_dir_all(dir).unwrap();
+        }
+        assert_eq!(validate_project_root(&root, None).unwrap(), root);
+        assert_eq!(validate_project_root(&root, Some(&root)).unwrap(), dunce::canonicalize(&root).unwrap());
+        assert!(validate_project_root(&root, Some(&member)).is_err());
+        ide_workspace::workspace::Workspace::save(&root, "Workspace", vec![member.clone()], true).unwrap();
+        assert_eq!(validate_project_root(&root, Some(&member)).unwrap(), dunce::canonicalize(&member).unwrap());
+        for rejected in [other, member.join("child"), member.join("../other"), "relative".into()] {
+            assert!(validate_project_root(&root, Some(&rejected)).is_err(), "{rejected:?}");
+        }
+    }
+}
@@ -39,12 +39,13 @@ fn load(project: &Project, languages: &LanguageRegistry, path: &Path) -> Option<
        let snap = project.documents.text_snapshot(doc).ok()?;
        return (!snap.large).then_some((snap.language, snap.text));
    }
-    let loaded = ide_vfs::load_text(path).ok()?;
+    let loaded = project.documents.load_file(path).ok()?;
    if loaded.binary || loaded.large || loaded.too_large {
        return None;
    }
-    let language = languages.detect(path, loaded.text.lines().next());
-    Some((language, loaded.text))
+    let text = ide_text::normalize_line_endings(&loaded.text).into_owned();
+    let language = languages.detect(path, text.lines().next());
+    Some((language, text))
 }

 // ---- Inspect Code ----
@@ -27,7 +27,12 @@ fn java_env(project_jdk: Option<&ide_sdk::java::Jdk>, release: Option<u32>) -> B
 /// The build model with the launch settings applied: the JDK (`JAVA_HOME`), and
 /// the Maven home and options from Settings › Maven.
 pub fn load(root: &Path, cache: &Path, settings: &Settings) -> BuildModel {
-    let mut model = ide_build::load(root, cache, ide_sdk::apply::maven_local_repository(root, settings));
+    let mut model = ide_build::load_linked(
+        root,
+        cache,
+        ide_sdk::apply::maven_local_repository(root, settings),
+        &settings.languages.java.maven,
+    );
    let jdk = ide_sdk::apply::project_jdk(root, settings);
    if let Some(m) = &mut model.maven {
        let mvn = ide_sdk::apply::maven_command(root, settings);
@@ -41,7 +46,8 @@ pub fn load(root: &Path, cache: &Path, settings: &Settings) -> BuildModel {
        }
    }
    if let Some(g) = &mut model.gradle {
-        g.env = java_env(jdk.as_ref(), g.java_version);
+        g.env = ide_sdk::apply::gradle_env(root, settings, java_env(jdk.as_ref(), g.java_version));
+        g.command = ide_sdk::apply::gradle_command(root, &root.join(&g.dir), settings).to_string_lossy().into_owned();
    }
    // A failed sync of a project no installed JDK can build says so first (with a Download JDK action).
    let missing = |release: Option<u32>| match jdk {
@@ -62,7 +68,7 @@ pub fn load(root: &Path, cache: &Path, settings: &Settings) -> BuildModel {
    if let Some(g) = &mut model.gradle
        && g.sync_error.is_some()
    {
-        let hint = missing(g.java_version);
+        let hint = if settings.languages.java.gradle.jvm.trim().is_empty() { missing(g.java_version) } else { None };
        explain(&mut g.sync_error, hint);
    }
    model
@@ -70,6 +76,7 @@ pub fn load(root: &Path, cache: &Path, settings: &Settings) -> BuildModel {

 /// Maven and Gradle projects of the window's project, from the build files plus the last sync.
 pub async fn build_model(host: &Host, window: &str) -> IdeResult<BuildModel> {
+    host.require_trust(window)?;
    let project = host.project(window)?;
    let (root, cache, settings) = (project.root.clone(), project.build_cache_dir(), project.settings.effective());
    tokio::task::spawn_blocking(move || load(&root, &cache, &settings)).await.map_err(join_err)
@@ -87,9 +94,11 @@ pub async fn build_sync(
    profiles: Vec<String>,
    on_progress: Channel<SyncProgress>,
 ) -> IdeResult<BuildModel> {
+    host.require_trust(window)?;
    let project = host.project(window)?;
    let (root, cache, settings) = (project.root.clone(), project.build_cache_dir(), project.settings.effective());
-    let token = host.begin_request(request);
+    let bridge_profiles = profiles.clone();
+    let token = host.begin_project_request(window, request);
    let result = tokio::task::spawn_blocking(move || {
        let current = load(&root, &cache, &settings);
        let env = match tool {
@@ -107,6 +116,8 @@ pub async fn build_sync(
            env,
            maven_command: ide_sdk::apply::maven_command(&root, &settings).map(|p| p.to_string_lossy().into_owned()),
            maven_options: ide_sdk::apply::maven_options(&root, &settings),
+            maven_settings: settings.languages.java.maven.clone(),
+            gradle_command: current.gradle.as_ref().map(|g| g.command.clone()),
        };
        let progress = |p: SyncProgress| {
            let _ = on_progress.send(p);
@@ -115,12 +126,30 @@ pub async fn build_sync(
            BuildTool::Maven => ide_build::sync_maven(&root, &cache, &options, &token, &progress)?,
            BuildTool::Gradle => ide_build::sync_gradle(&root, &cache, &options, &token, &progress)?,
        }
-        Ok(load(&root, &cache, &settings))
+        Ok::<BuildModel, IdeError>(load(&root, &cache, &settings))
    })
    .await
    .map_err(join_err);
    host.end_request(request);
-    result?
+    let model = result??;
+    if tool == BuildTool::Maven
+        && let Some(maven) = &model.maven
+    {
+        // jdtls re-imports on pom changes but misses artifacts added to ~/.m2
+        // meanwhile ("missing artifact" stays until Invalidate Caches); asking it
+        // to update the project configurations re-resolves them (#436).
+        if let Some(bridge) = &project.kotlin_bridge {
+            bridge.configure_maven(offline, bridge_profiles);
+        }
+        let lsp = project.lsp.clone();
+        let uris = maven.projects.iter().map(|p| ide_lsp::path_to_uri_string(&project.root.join(&p.pom))).collect();
+        tokio::spawn(async move {
+            if let Err(e) = lsp.java_update_project_configs(&project.root, uris).await {
+                tracing::debug!("java/projectConfigurationsUpdate: {e}");
+            }
+        });
+    }
+    Ok(model)
 }

 /// The POM declaring `dependency` for the Maven module `pom` (project-relative): the
@@ -200,10 +229,12 @@ pub async fn build_run(
    clear: Vec<std::path::PathBuf>,
    on_event: Channel<BuildEvent>,
 ) -> IdeResult<BuildResult> {
+    host.require_trust(window)?;
    let project = host.project(window)?;
    let (root, cache, sink) = (project.root.clone(), project.build_cache_dir(), project.sink.clone());
    let settings = project.settings.effective();
-    let token = host.begin_request(request);
+    let config_dir = host.config_dir.clone();
+    let token = host.begin_project_request(window, request);
    let result = tokio::task::spawn_blocking(move || {
        for path in clear {
            sink.emit(IdeEvent::Diagnostics {
@@ -212,7 +243,23 @@ pub async fn build_run(
                items: Vec::new(),
            });
        }
-        let plan = compile::plan(&root, &load(&root, &cache, &settings), kind, file.as_deref())?;
+        let plan = if let Some(workspace) = ide_workspace::workspace::Workspace::load(&root)? {
+            let mut combined: Option<compile::BuildPlan> = None;
+            for member in workspace.projects.iter().filter(|p| file.as_ref().is_none_or(|f| f.starts_with(p))) {
+                let settings = ide_workspace::SettingsStore::load(&config_dir, Some(member)).effective();
+                let member_cache = cache.join(crate::project::project_key(member));
+                let plan = compile::plan(member, &load(member, &member_cache, &settings), kind, file.as_deref())?;
+                match &mut combined {
+                    Some(combined) => combined.steps.extend(plan.steps),
+                    None => combined = Some(plan),
+                }
+            }
+            let mut plan = combined.ok_or_else(|| IdeError::invalid("No workspace project to build"))?;
+            plan.title = workspace.name;
+            plan
+        } else {
+            compile::plan(&root, &load(&root, &cache, &settings), kind, file.as_deref())?
+        };
        let result = compile::run(&root, &plan, &token, &|e| {
            let _ = on_event.send(e);
        })?;
@@ -261,3 +308,34 @@ pub(crate) fn register(d: &mut Dispatcher) {
        .await
    });
 }
+
+#[cfg(test)]
+mod gradle_settings_tests {
+    use super::*;
+
+    #[test]
+    fn model_for_sync_tasks_and_compile_uses_gradle_settings() {
+        let tmp = tempfile::tempdir().unwrap();
+        let root = tmp.path();
+        std::fs::write(root.join("build.gradle"), "plugins { id 'java' }").unwrap();
+        let wrapper = root.join(if cfg!(windows) { "gradlew.bat" } else { "gradlew" });
+        std::fs::write(&wrapper, "").unwrap();
+        let mut settings = Settings::default();
+        let default = load(root, &root.join("cache"), &settings).gradle.unwrap();
+        assert_eq!(default.command, wrapper.to_string_lossy());
+        settings.languages.java.gradle.jvm = "jdk21".into();
+        settings.languages.java.gradle.user_home = "user-home".into();
+        settings.languages.java.gradle.distribution = ide_core::settings::GradleDistribution::Local;
+        settings.languages.java.gradle.home = "gradle-install".into();
+        let model = load(root, &root.join("cache"), &settings).gradle.unwrap();
+        assert_eq!(
+            model.command,
+            root.join("gradle-install")
+                .join("bin")
+                .join(if cfg!(windows) { "gradle.bat" } else { "gradle" })
+                .to_string_lossy()
+        );
+        assert_eq!(model.env["JAVA_HOME"], root.join("jdk21").to_string_lossy());
+        assert_eq!(model.env["GRADLE_USER_HOME"], root.join("user-home").to_string_lossy());
+    }
+}
@@ -16,6 +16,7 @@ pub async fn blocking<T: Send + 'static>(f: impl FnOnce() -> IdeResult<T> + Send
 /// How to run `config` with coverage: the command to launch and where its report will be,
 /// or which tool is missing.
 pub async fn coverage_prepare(host: &Host, window: &str, config: RunConfig) -> IdeResult<CoveragePrepared> {
+    host.require_trust(window)?;
    let project = host.project(window)?;
    let (root, cache) = (project.root.clone(), project.cache_dir.join("coverage"));
    blocking(move || {
@@ -26,7 +27,8 @@ pub async fn coverage_prepare(host: &Host, window: &str, config: RunConfig) -> I
 }

 /// Reads the report a coverage run left behind.
-pub async fn coverage_collect(_host: &Host, _window: &str, report: CoverageReportSpec) -> IdeResult<CoverageSuite> {
+pub async fn coverage_collect(host: &Host, window: &str, report: CoverageReportSpec) -> IdeResult<CoverageSuite> {
+    host.require_trust(window)?;
    blocking(move || ide_coverage::collect(&report)).await
 }

@@ -1,3 +1,5 @@
+mod output;
+
 use crate::Host;
 use crate::rpc::Dispatcher;
 use ide_core::{DebugSessionId, IdeResult};
@@ -6,6 +8,7 @@ use std::path::PathBuf;

 /// Starts a session owned by this window: its events (and those of child sessions) go here only.
 pub async fn debug_start(host: &Host, window: &str, config: LaunchConfig) -> IdeResult<DebugSessionId> {
+    host.require_trust(window)?;
    let mut config = match_java_debug_encoding(config, cfg!(windows));
    if config.adapter == "debugpy"
        && config.request == "launch"
@@ -14,17 +17,70 @@ pub async fn debug_start(host: &Host, window: &str, config: LaunchConfig) -> Ide
        super::python::prepare_debug(&mut config, &super::python::paths(&project))?;
    }
    let label = window;
-    let owner = SessionOwner::new(host.owner_window(label), host.window_sink(label));
+    let (sink, flush_output) = output::coalescing_sink(host.window_sink(label));
+    let owner = SessionOwner::new(host.owner_window(label), sink);
    let settings = match host.project(label) {
        Ok(project) => project.settings.effective(),
        Err(_) => host.global_settings.effective(),
    };
+    if config.adapter == "delve" && config.request == "launch" {
+        let root = host.project(window).map(|p| p.root.clone()).unwrap_or_default();
+        let settings = settings.clone();
+        config = host
+            .blocking(move || {
+                ide_sdk::go::debug_environment(&root, &settings, &mut config.env);
+                ide_sdk::go::apply_to_debug(
+                    &mut config.env,
+                    &mut config.extra_json,
+                    &settings.languages.go.build_tags,
+                )?;
+                Ok(config)
+            })
+            .await?;
+    }
+    if config.adapter == ide_dap::kotlin::ADAPTER {
+        let data_dir = host.data_dir.clone();
+        let runtime_root = config.cwd.clone().map(PathBuf::from).unwrap_or_default();
+        let runtime_settings = settings.clone();
+        let runtime = host
+            .blocking(move || {
+                if let Some(jdk) = ide_sdk::apply::jdtls_jdk(&runtime_root, &runtime_settings)
+                    .map_err(ide_core::IdeError::unavailable)?
+                {
+                    if jdk.major >= 11 {
+                        return Ok(jdk);
+                    }
+                    return Err(ide_core::IdeError::unavailable(
+                        "Kotlin debugger needs JDK 11 or newer. Choose a newer language server JDK in Settings.",
+                    ));
+                }
+                let jdks = ide_sdk::java::jdtls_jdks(11, &data_dir);
+                ide_sdk::java::jdtls_runtime(&jdks, 11).cloned().ok_or_else(|| {
+                    ide_core::IdeError::unavailable(
+                        "Kotlin debugger needs JDK 11 or newer. Download or choose a language server JDK in Settings.",
+                    )
+                })
+            })
+            .await?;
+        let mut extra: serde_json::Value = config
+            .extra_json
+            .as_deref()
+            .map(serde_json::from_str)
+            .transpose()
+            .map_err(|e| ide_core::IdeError::invalid(e.to_string()))?
+            .unwrap_or_else(|| serde_json::json!({}));
+        extra["__adapterJavaHome"] = serde_json::json!(runtime.home);
+        config.extra_json = Some(extra.to_string());
+    }
    let root = config.cwd.clone().map(PathBuf::from).unwrap_or_default();
    let custom = |command: &str| {
        let path = ide_sdk::apply::tool_command(&root, &settings, command)?;
        Some(path.to_string_lossy().into_owned())
    };
-    host.debugger.start_with(config, owner, custom).await
+    host.require_trust(window)?;
+    let result = host.debugger.start_with(config, owner, custom).await;
+    flush_output();
+    result
 }

 /// A JVM launched by java-debug writes what java-debug decodes its output as
@@ -40,7 +96,13 @@ fn match_java_debug_encoding(mut config: LaunchConfig, windows: bool) -> LaunchC
    };
    let vm_args = extra.get("vmArgs").and_then(|v| v.as_str()).unwrap_or_default();
    let encoding = extra.get("encoding").and_then(|v| v.as_str());
-    if let Some(vm_args) = ide_core::output_encoding::java_debug_vm_args(vm_args, encoding, windows) {
+    if let Some(vm_args) = ide_core::output_encoding::java_debug_vm_args(
+        vm_args,
+        &config.env,
+        |key| std::env::var(key).ok(),
+        encoding,
+        windows,
+    ) {
        extra.insert("vmArgs".into(), vm_args.into());
        config.extra_json = Some(serde_json::Value::Object(extra).to_string());
    }
@@ -253,11 +315,12 @@ pub async fn debug_attachable_processes(_host: &Host, _window: &str) -> IdeResul
 /// JVM to connect to `host:port`; returns the loopback port java-debug attaches to.
 pub async fn debug_listen_for_jvm(
    host: &Host,
-    _window: &str,
+    window: &str,
    request: ide_core::RequestId,
    jvm_host: String,
    port: u16,
 ) -> IdeResult<u16> {
+    host.require_trust(window)?;
    let token = host.begin_request(request);
    let result = jdwp::listen_for_jvm(&jvm_host, port, token).await;
    host.end_request(request);
@@ -395,7 +458,7 @@ mod tests {
            program: None,
            args: vec![],
            cwd: None,
-            env: Default::default(),
+            env: [("JDK_JAVA_OPTIONS".into(), "".into()), ("JAVA_TOOL_OPTIONS".into(), "".into())].into(),
            extra_json: Some(extra.to_string()),
        }
    }
@@ -411,7 +474,7 @@ mod tests {
        let fixed = match_java_debug_encoding(launch("java-debug", "launch", extra.clone()), true);
        assert_eq!(
            vm_args(&fixed),
-            "-Xmx1g -Dstdout.encoding=UTF-8 -Dstderr.encoding=UTF-8 -Dsun.stdout.encoding=UTF-8 -Dsun.stderr.encoding=UTF-8"
+            "-Xmx1g -Dstdout.encoding=UTF-8 -Dstderr.encoding=UTF-8 -Dsun.stdout.encoding=UTF-8 -Dsun.stderr.encoding=UTF-8 -Dfile.encoding=UTF-8"
        );
        assert_eq!(
            serde_json::from_str::<serde_json::Value>(fixed.extra_json.as_deref().unwrap()).unwrap()["mainClass"],
@@ -424,4 +487,13 @@ mod tests {
            assert_eq!(vm_args(&match_java_debug_encoding(launch(adapter, request, extra.clone()), windows)), "-Xmx1g");
        }
    }
+
+    #[test]
+    fn java_debug_launches_respect_environment_encoding() {
+        for key in ["JDK_JAVA_OPTIONS", "JAVA_TOOL_OPTIONS"] {
+            let mut config = launch("java-debug", "launch", serde_json::json!({"vmArgs": "-Dstdout.encoding=GBK"}));
+            config.env.insert(key.into(), "-Dfile.encoding=GBK".into());
+            assert_eq!(vm_args(&match_java_debug_encoding(config, true)), "-Dstdout.encoding=GBK");
+        }
+    }
 }
@@ -0,0 +1,182 @@
+use ide_core::event::DebugEvent;
+use ide_core::{DebugSessionId, IdeEvent, SharedSink};
+use parking_lot::Mutex;
+use std::collections::HashMap;
+use std::sync::Arc;
+use std::time::Duration;
+
+const WINDOW: Duration = Duration::from_millis(50);
+const MAX_BYTES: usize = 64 * 1024;
+
+#[derive(Default)]
+struct Pending {
+    sessions: HashMap<DebugSessionId, (String, String)>,
+    scheduled: bool,
+}
+
+fn flush(pending: &mut Pending, sink: &SharedSink, session: DebugSessionId) {
+    if let Some((category, output)) = pending.sessions.remove(&session) {
+        sink.emit(IdeEvent::Debug { session, event: DebugEvent::Output { category, output } });
+    }
+}
+
+/// All debug output sources (including build output and child sessions) share this
+/// bounded batch before reaching desktop or remote IPC. Control events flush
+/// their session first, so a stop or exit cannot overtake preceding output.
+pub(super) fn coalescing_sink(sink: SharedSink) -> (SharedSink, impl Fn()) {
+    let pending = Arc::new(Mutex::new(Pending::default()));
+    let flush_pending = {
+        let pending = pending.clone();
+        let sink = sink.clone();
+        move || {
+            let mut state = pending.lock();
+            for (session, (category, output)) in state.sessions.drain() {
+                sink.emit(IdeEvent::Debug { session, event: DebugEvent::Output { category, output } });
+            }
+        }
+    };
+    let runtime = tokio::runtime::Handle::current();
+    let output: SharedSink = Arc::new(move |event| {
+        let mut state = pending.lock();
+        match event {
+            IdeEvent::Debug { session, event: DebugEvent::Output { category, output } } => {
+                if output.is_empty() {
+                    return;
+                }
+                if state.sessions.get(&session).is_some_and(|(c, _)| *c != category) {
+                    flush(&mut state, &sink, session);
+                }
+                let mut rest = output.as_str();
+                while !rest.is_empty() {
+                    let (_, text) = state.sessions.entry(session).or_insert_with(|| (category.clone(), String::new()));
+                    let mut end = rest.len().min(MAX_BYTES - text.len());
+                    while !rest.is_char_boundary(end) {
+                        end -= 1;
+                    }
+                    text.push_str(&rest[..end]);
+                    rest = &rest[end..];
+                    if text.len() == MAX_BYTES || !rest.is_empty() {
+                        flush(&mut state, &sink, session);
+                    }
+                }
+                if !state.scheduled && !state.sessions.is_empty() {
+                    state.scheduled = true;
+                    let pending = pending.clone();
+                    let sink = sink.clone();
+                    runtime.spawn(async move {
+                        tokio::time::sleep(WINDOW).await;
+                        let mut state = pending.lock();
+                        for (session, (category, output)) in state.sessions.drain() {
+                            sink.emit(IdeEvent::Debug { session, event: DebugEvent::Output { category, output } });
+                        }
+                        state.scheduled = false;
+                    });
+                }
+            }
+            IdeEvent::Debug { session, event } => {
+                flush(&mut state, &sink, session);
+                sink.emit(IdeEvent::Debug { session, event });
+            }
+            event => sink.emit(event),
+        }
+    });
+    (output, flush_pending)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn setup() -> (SharedSink, Arc<Mutex<Vec<IdeEvent>>>) {
+        let events = Arc::new(Mutex::new(Vec::new()));
+        let saved = events.clone();
+        (coalescing_sink(Arc::new(move |event| saved.lock().push(event))).0, events)
+    }
+
+    fn output(sink: &SharedSink, session: u32, category: &str, output: &str) {
+        sink.emit(IdeEvent::Debug {
+            session: DebugSessionId(session),
+            event: DebugEvent::Output { category: category.into(), output: output.into() },
+        });
+    }
+
+    #[tokio::test(start_paused = true)]
+    async fn explicit_start_completion_flush_does_not_duplicate_output() {
+        let events = Arc::new(Mutex::new(Vec::new()));
+        let saved = events.clone();
+        let (sink, flush) = coalescing_sink(Arc::new(move |event| saved.lock().push(event)));
+        output(&sink, 1, "console", "build failed\n");
+        flush();
+        assert_eq!(events.lock().len(), 1);
+        tokio::task::yield_now().await;
+        tokio::time::advance(WINDOW).await;
+        tokio::task::yield_now().await;
+        assert_eq!(events.lock().len(), 1);
+    }
+
+    #[tokio::test(start_paused = true)]
+    async fn batches_per_session_and_flushes_idle_output() {
+        let (sink, events) = setup();
+        for _ in 0..500 {
+            output(&sink, 1, "stdout", "line\n");
+        }
+        output(&sink, 2, "stdout", "other\n");
+        assert!(events.lock().is_empty());
+        tokio::task::yield_now().await;
+        tokio::time::advance(WINDOW).await;
+        tokio::task::yield_now().await;
+        let events = events.lock();
+        assert_eq!(events.len(), 2);
+        assert!(events.iter().any(|event| matches!(event,
+            IdeEvent::Debug { session: DebugSessionId(1), event: DebugEvent::Output { output, .. } }
+            if output == &"line\n".repeat(500))));
+    }
+
+    #[tokio::test]
+    async fn categories_and_control_events_keep_order() {
+        let (sink, events) = setup();
+        output(&sink, 1, "stdout", "out");
+        output(&sink, 1, "stderr", "err");
+        sink.emit(IdeEvent::Debug { session: DebugSessionId(1), event: DebugEvent::Terminated });
+        let events = events.lock();
+        assert_eq!(events.len(), 3);
+        assert!(matches!(&events[0], IdeEvent::Debug { event: DebugEvent::Output { category, output }, .. }
+            if category == "stdout" && output == "out"));
+        assert!(matches!(&events[1], IdeEvent::Debug { event: DebugEvent::Output { category, output }, .. }
+            if category == "stderr" && output == "err"));
+        assert!(matches!(&events[2], IdeEvent::Debug { event: DebugEvent::Terminated, .. }));
+    }
+
+    #[tokio::test(start_paused = true)]
+    async fn terminating_one_session_preserves_other_pending_output() {
+        let (sink, events) = setup();
+        output(&sink, 1, "stdout", "first");
+        output(&sink, 2, "stdout", "second");
+        sink.emit(IdeEvent::Debug { session: DebugSessionId(1), event: DebugEvent::Terminated });
+        assert_eq!(events.lock().len(), 2);
+        tokio::task::yield_now().await;
+        tokio::time::advance(WINDOW).await;
+        tokio::task::yield_now().await;
+        let events = events.lock();
+        assert_eq!(events.len(), 3);
+        assert!(matches!(&events[2],
+            IdeEvent::Debug { session: DebugSessionId(2), event: DebugEvent::Output { output, .. } }
+            if output == "second"));
+    }
+
+    #[tokio::test]
+    async fn large_unicode_events_are_bounded_without_loss() {
+        let (sink, events) = setup();
+        let text = "日志\n".repeat(100_000);
+        output(&sink, 1, "stdout", &text);
+        sink.emit(IdeEvent::Debug { session: DebugSessionId(1), event: DebugEvent::Terminated });
+        let mut combined = String::new();
+        for event in events.lock().iter() {
+            if let IdeEvent::Debug { event: DebugEvent::Output { output, .. }, .. } = event {
+                assert!(output.len() <= MAX_BYTES);
+                combined.push_str(output);
+            }
+        }
+        assert_eq!(combined, text);
+    }
+}
@@ -0,0 +1,207 @@
+use crate::Host;
+use ide_core::{CancellationToken, IdeEvent, IdeResult, IpcPath, RequestId, SharedSink, TaskId};
+use ide_remote::{DeployedPath, DeploymentCoverage, SyncEntry, SyncStep, TransferReport};
+use ide_ssh::{FsConnection, RemoteEntry};
+use std::path::PathBuf;
+
+/// Reports a transfer as a background task (status bar progress) whose Cancel fires `token`.
+fn progress(
+    sink: SharedSink,
+    title: &str,
+    token: CancellationToken,
+) -> (impl FnMut(&str, usize, usize) + Send, impl FnOnce()) {
+    let id = TaskId::next();
+    let cancel = token;
+    let handle = ide_core::task::on_cancel(id, move || cancel.cancel());
+    let title = title.to_owned();
+    let (s, t) = (sink.clone(), title.clone());
+    let report = move |path: &str, i: usize, n: usize| {
+        let fraction = if n == 0 { None } else { Some(i as f32 / n as f32) };
+        let message = Some(path.to_owned());
+        s.emit(IdeEvent::Task { id, title: t.clone(), message, fraction, done: false, cancellable: true });
+    };
+    let done = move || {
+        drop(handle);
+        sink.emit(IdeEvent::Task { id, title, message: None, fraction: Some(1.0), done: true, cancellable: false })
+    };
+    (report, done)
+}
+
+fn local(paths: Vec<IpcPath>) -> Vec<PathBuf> {
+    paths.into_iter().map(|p| p.to_path_buf()).collect()
+}
+
+/// Eligible paths per server, without contacting any deployment host.
+pub async fn deploy_coverage(window: &str, state: &Host, paths: Vec<IpcPath>) -> IdeResult<Vec<DeploymentCoverage>> {
+    let project = state.project(window)?;
+    Ok(ide_remote::coverage(&project.settings.effective(), &project.root, &local(paths)))
+}
+
+/// Tools › Deployment › Upload to…: files and folders to `server` (default server when `None`).
+pub async fn deploy_upload(
+    window: &str,
+    state: &Host,
+    paths: Vec<IpcPath>,
+    server: Option<String>,
+    request: RequestId,
+) -> IdeResult<TransferReport> {
+    let project = state.project(window)?;
+    let token = state.begin_request(request);
+    let (mut report, done) = progress(project.sink.clone(), "Uploading", token.clone());
+    let r = state
+        .remote
+        .upload(&project.settings.effective(), &project.root, server.as_deref(), &local(paths), token, &mut report)
+        .await;
+    done();
+    state.end_request(request);
+    r
+}
+
+/// Download from…: the remote counterparts of files and folders.
+pub async fn deploy_download(
+    window: &str,
+    state: &Host,
+    paths: Vec<IpcPath>,
+    server: Option<String>,
+    request: RequestId,
+) -> IdeResult<TransferReport> {
+    let project = state.project(window)?;
+    let token = state.begin_request(request);
+    let (mut report, done) = progress(project.sink.clone(), "Downloading", token.clone());
+    let r = state
+        .remote
+        .download(&project.settings.effective(), &project.root, server.as_deref(), &local(paths), token, &mut report)
+        .await;
+    done();
+    state.end_request(request);
+    r
+}
+
+/// Deletes the remote counterparts of files and folders.
+pub async fn deploy_delete_remote(
+    window: &str,
+    state: &Host,
+    paths: Vec<IpcPath>,
+    server: Option<String>,
+) -> IdeResult<TransferReport> {
+    let project = state.project(window)?;
+    state.remote.delete_remote(&project.settings.effective(), &project.root, server.as_deref(), &local(paths)).await
+}
+
+/// Sync with Deployed: local and remote files under `path`, side by side.
+pub async fn deploy_compare(
+    window: &str,
+    state: &Host,
+    path: IpcPath,
+    server: Option<String>,
+    request: RequestId,
+) -> IdeResult<Vec<SyncEntry>> {
+    let project = state.project(window)?;
+    let token = state.begin_request(request);
+    let r = state.remote.compare(&project.settings.effective(), &project.root, server.as_deref(), &path, token).await;
+    state.end_request(request);
+    r
+}
+
+/// Applies the Sync with Deployed choices.
+pub async fn deploy_sync(
+    window: &str,
+    state: &Host,
+    steps: Vec<SyncStep>,
+    server: Option<String>,
+    request: RequestId,
+) -> IdeResult<TransferReport> {
+    let project = state.project(window)?;
+    let token = state.begin_request(request);
+    let (mut report, done) = progress(project.sink.clone(), "Synchronizing", token.clone());
+    let r = state
+        .remote
+        .sync(&project.settings.effective(), &project.root, server.as_deref(), &steps, token, &mut report)
+        .await;
+    done();
+    state.end_request(request);
+    r
+}
+
+/// Where `path` is deployed (remote path, web URL); `None` when not mapped.
+pub async fn deploy_info(
+    window: &str,
+    state: &Host,
+    path: IpcPath,
+    server: Option<String>,
+) -> IdeResult<Option<DeployedPath>> {
+    let project = state.project(window)?;
+    state.remote.deployed(&project.settings.effective(), &project.root, server.as_deref(), &path).await
+}
+
+/// Remote Host tool window: the server root of `server`, resolved on the host.
+pub async fn deploy_server_root(window: &str, state: &Host, server: String) -> IdeResult<String> {
+    let settings = match state.project(window) {
+        Ok(p) => p.settings.effective(),
+        Err(_) => state.global_settings.effective(),
+    };
+    state.remote.server_root(&settings, &server).await
+}
+
+/// Entries of a folder on the selected filesystem (`~`: its home directory).
+pub async fn remote_list(state: &Host, connection: FsConnection, path: String) -> IdeResult<Vec<RemoteEntry>> {
+    state.remote.list(&connection, &path).await
+}
+
+/// Opens a remote file for editing: a local copy, uploaded back on save.
+pub async fn remote_open(state: &Host, connection: FsConnection, path: String) -> IdeResult<IpcPath> {
+    Ok(state.remote.open_remote(&connection, &path).await?.into())
+}
+
+/// The filesystem connection and path a cached editing copy stands for.
+pub fn remote_of(state: &Host, path: IpcPath) -> Option<(FsConnection, String)> {
+    state.remote.remote_of(&path)
+}
+
+pub async fn remote_delete(state: &Host, connection: FsConnection, path: String) -> IdeResult<()> {
+    state.remote.remote_delete(&connection, &path).await
+}
+
+pub async fn remote_mkdir(state: &Host, connection: FsConnection, path: String) -> IdeResult<()> {
+    state.remote.remote_mkdir(&connection, &path).await
+}
+
+pub async fn remote_rename(state: &Host, connection: FsConnection, from: String, to: String) -> IdeResult<()> {
+    state.remote.remote_rename(&connection, &from, &to).await
+}
+
+pub async fn deploy_test_connection(state: &Host, connection: FsConnection, path: String) -> IdeResult<()> {
+    state.remote.test_connection(&connection, &path).await
+}
+
+pub(crate) fn register(d: &mut crate::rpc::Dispatcher) {
+    d.add("deploy_coverage", |c| async move { deploy_coverage(&c.window, &c.host, c.arg("paths")?).await });
+    d.add("deploy_upload", |c| async move {
+        deploy_upload(&c.window, &c.host, c.arg("paths")?, c.arg("server")?, c.arg("request")?).await
+    });
+    d.add("deploy_download", |c| async move {
+        deploy_download(&c.window, &c.host, c.arg("paths")?, c.arg("server")?, c.arg("request")?).await
+    });
+    d.add("deploy_delete_remote", |c| async move {
+        deploy_delete_remote(&c.window, &c.host, c.arg("paths")?, c.arg("server")?).await
+    });
+    d.add("deploy_compare", |c| async move {
+        deploy_compare(&c.window, &c.host, c.arg("path")?, c.arg("server")?, c.arg("request")?).await
+    });
+    d.add("deploy_sync", |c| async move {
+        deploy_sync(&c.window, &c.host, c.arg("steps")?, c.arg("server")?, c.arg("request")?).await
+    });
+    d.add("deploy_info", |c| async move { deploy_info(&c.window, &c.host, c.arg("path")?, c.arg("server")?).await });
+    d.add("deploy_server_root", |c| async move { deploy_server_root(&c.window, &c.host, c.arg("server")?).await });
+    d.add("remote_list", |c| async move { remote_list(&c.host, c.arg("connection")?, c.arg("path")?).await });
+    d.add("remote_open", |c| async move { remote_open(&c.host, c.arg("connection")?, c.arg("path")?).await });
+    d.add("remote_of", |c| async move { Ok(remote_of(&c.host, c.arg("path")?)) });
+    d.add("remote_delete", |c| async move { remote_delete(&c.host, c.arg("connection")?, c.arg("path")?).await });
+    d.add("remote_mkdir", |c| async move { remote_mkdir(&c.host, c.arg("connection")?, c.arg("path")?).await });
+    d.add("remote_rename", |c| async move {
+        remote_rename(&c.host, c.arg("connection")?, c.arg("from")?, c.arg("to")?).await
+    });
+    d.add("deploy_test_connection", |c| async move {
+        deploy_test_connection(&c.host, c.arg("connection")?, c.arg("path")?).await
+    });
+}
@@ -28,12 +28,26 @@ pub fn edit(host: &Host, window: &str, doc: DocId, base_version: u32, changes: C

 pub async fn save(host: &Host, window: &str, doc: DocId) -> IdeResult<()> {
    let project = host.project(window)?;
-    host.blocking(move || project.documents.save(doc)).await
+    host.blocking(move || project.documents.save(doc)).await?;
+    host.debugger.refresh_source_mirrors(host.owner_window(window)).await
 }

 pub async fn save_all(host: &Host, window: &str) -> IdeResult<()> {
    let project = host.project(window)?;
-    host.blocking(move || project.documents.save_all()).await
+    host.blocking(move || project.documents.save_all()).await?;
+    host.debugger.refresh_source_mirrors(host.owner_window(window)).await
+}
+
+/// Recovers external changes missed by the project's file watchers.
+pub async fn sync_from_disk(host: &Host, window: &str) -> IdeResult<()> {
+    let project = host.project(window)?;
+    host.blocking(move || {
+        if project.settings.effective().files.sync_on_focus {
+            project.documents.sync_from_disk();
+        }
+        Ok(())
+    })
+    .await
 }

 pub async fn snapshot(host: &Host, window: &str, doc: DocId) -> IdeResult<DocumentInfo> {
@@ -43,3 +57,6 @@ pub async fn snapshot(host: &Host, window: &str, doc: DocId) -> IdeResult<Docume

 mod commands;
 pub use commands::*;
+
+#[cfg(test)]
+mod tests;
@@ -22,9 +22,23 @@ pub async fn doc_open_virtual(host: &Host, window: &str, uri: String) -> IdeResu
    blocking(move || project.documents.open_virtual(&vd.uri, vd.language_id, &vd.text)).await
 }

+/// The CodeMirror mode `path` gets when opened (`DocumentInfo::ui_mode`),
+/// without opening it: previews of closed files.
+pub async fn doc_ui_mode(host: &Host, window: &str, path: PathBuf) -> IdeResult<Option<String>> {
+    let project = host.project(window)?;
+    blocking(move || Ok(project.documents.ui_mode_of(&path))).await
+}
+
 /// "Reload with Encoding" (`reload`) or "Convert to Encoding"; returns the new encoding label.
-pub fn doc_set_encoding(host: &Host, window: &str, doc: DocId, encoding: String, reload: bool) -> IdeResult<String> {
-    host.project(window)?.documents.set_encoding(doc, &encoding, reload)
+pub async fn doc_set_encoding(
+    host: &Host,
+    window: &str,
+    doc: DocId,
+    encoding: String,
+    reload: bool,
+) -> IdeResult<String> {
+    let project = host.project(window)?;
+    host.blocking(move || project.documents.set_encoding(doc, &encoding, reload)).await
 }

 pub fn doc_set_line_ending(host: &Host, window: &str, doc: DocId, line_ending: LineEnding) -> IdeResult<()> {
@@ -108,8 +122,9 @@ pub fn history_content(host: &Host, window: &str, id: String) -> IdeResult<Strin
 /// Commands of this module the remote server answers.
 pub(crate) fn register(d: &mut Dispatcher) {
    d.add("doc_open_virtual", |c| async move { doc_open_virtual(&c.host, &c.window, c.arg("uri")?).await });
+    d.add("doc_ui_mode", |c| async move { doc_ui_mode(&c.host, &c.window, c.arg("path")?).await });
    d.add("doc_set_encoding", |c| async move {
-        doc_set_encoding(&c.host, &c.window, c.arg("doc")?, c.arg("encoding")?, c.arg("reload")?)
+        doc_set_encoding(&c.host, &c.window, c.arg("doc")?, c.arg("encoding")?, c.arg("reload")?).await
    });
    d.add("doc_set_line_ending", |c| async move {
        doc_set_line_ending(&c.host, &c.window, c.arg("doc")?, c.arg("lineEnding")?)
@@ -0,0 +1,200 @@
+use super::*;
+use crate::{HostConfig, Project};
+use ide_core::{IdeEvent, TextChange, event::NotifyLevel};
+use parking_lot::Mutex;
+use std::{path::Path, sync::Arc};
+
+struct Fixture {
+    host: Host,
+    project: Arc<Project>,
+    events: Arc<Mutex<Vec<IdeEvent>>>,
+    path: PathBuf,
+    outside: PathBuf,
+    _temp: tempfile::TempDir,
+}
+
+impl Fixture {
+    fn new() -> Self {
+        let temp = tempfile::tempdir().unwrap();
+        let base = dunce::canonicalize(temp.path()).unwrap();
+        let root = base.join("project");
+        // Keep watcher delivery out of these tests: the op must recover it itself.
+        let excluded = root.join("node_modules");
+        std::fs::create_dir_all(&excluded).unwrap();
+        let path = excluded.join("file.txt");
+        let outside = base.join("outside.txt");
+        std::fs::write(&path, "original\n").unwrap();
+        std::fs::write(&outside, "outside\n").unwrap();
+        let events = Arc::new(Mutex::new(Vec::new()));
+        let captured = events.clone();
+        let host = Host::new(HostConfig {
+            config_dir: base.join("config"),
+            data_dir: base.join("data"),
+            languages: Arc::new(ide_language::LanguageRegistry::load(None).unwrap()),
+            syntax: Arc::default(),
+            sink_for: Box::new(move |_| {
+                let events = captured.clone();
+                Arc::new(move |event| events.lock().push(event))
+            }),
+            owner: |w| w,
+            runtime: tokio::runtime::Handle::current(),
+            project_environment: false,
+        });
+        let project = host.open_project("main", &root).unwrap();
+        Self { _temp: temp, host, project, events, path, outside }
+    }
+
+    async fn open(&self, path: &Path) -> DocumentInfo {
+        open(&self.host, "main", path.to_path_buf()).await.unwrap()
+    }
+
+    async fn sync(&self) {
+        sync_from_disk(&self.host, "main").await.unwrap();
+    }
+
+    fn document_events(&self) -> Vec<IdeEvent> {
+        self.events
+            .lock()
+            .iter()
+            .filter(|e| matches!(e, IdeEvent::DocPatched { .. } | IdeEvent::DocDirty { .. } | IdeEvent::Notify { .. }))
+            .cloned()
+            .collect()
+    }
+}
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn changed_clean_document_reloads_once() {
+    let f = Fixture::new();
+    let original = f.open(&f.path).await;
+    std::fs::write(&f.path, "externally changed\n").unwrap();
+    f.sync().await;
+    let loaded = f.project.documents.snapshot(original.id).unwrap();
+    assert_eq!(loaded.text, "externally changed\n");
+    assert!(!loaded.dirty);
+    assert!(loaded.version > original.version);
+    f.events.lock().clear();
+    f.sync().await;
+    assert_eq!(f.project.documents.snapshot(original.id).unwrap().version, loaded.version);
+    assert!(f.document_events().is_empty());
+}
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn unchanged_document_has_no_patch_or_event() {
+    let f = Fixture::new();
+    let original = f.open(&f.path).await;
+    f.events.lock().clear();
+    f.sync().await;
+    let loaded = f.project.documents.snapshot(original.id).unwrap();
+    assert_eq!(loaded.text, original.text);
+    assert_eq!(loaded.version, original.version);
+    assert!(f.document_events().is_empty());
+}
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn dirty_document_keeps_edits_and_warns_once() {
+    let f = Fixture::new();
+    let original = f.open(&f.path).await;
+    edit(
+        &f.host,
+        "main",
+        original.id,
+        original.version,
+        ChangeSet { changes: vec![TextChange { from: 0, to: 0, insert: "local ".into() }] },
+    )
+    .unwrap();
+    f.events.lock().clear();
+    std::fs::write(&f.path, "external replacement\n").unwrap();
+    f.sync().await;
+    let loaded = f.project.documents.snapshot(original.id).unwrap();
+    assert_eq!(loaded.text, "local original\n");
+    assert!(loaded.dirty);
+    assert!(matches!(f.document_events().as_slice(), [IdeEvent::Notify { level: NotifyLevel::Warning, .. }]));
+    f.events.lock().clear();
+    f.sync().await;
+    assert!(f.document_events().is_empty());
+}
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn deleted_document_keeps_its_buffer_and_other_documents_still_reload() {
+    let f = Fixture::new();
+    let original = f.open(&f.path).await;
+    let outside = f.open(&f.outside).await;
+    std::fs::remove_file(&f.path).unwrap();
+    std::fs::write(&f.outside, "outside changed after deletion\n").unwrap();
+    f.sync().await;
+    let loaded = f.project.documents.snapshot(original.id).unwrap();
+    assert_eq!(loaded.text, original.text);
+    assert_eq!(loaded.version, original.version);
+    assert_eq!(f.project.documents.snapshot(outside.id).unwrap().text, "outside changed after deletion\n");
+}
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn outside_project_document_reloads() {
+    let f = Fixture::new();
+    assert!(!f.outside.starts_with(&f.project.root));
+    let original = f.open(&f.outside).await;
+    std::fs::write(&f.outside, "outside changed externally\n").unwrap();
+    f.sync().await;
+    assert_eq!(f.project.documents.snapshot(original.id).unwrap().text, "outside changed externally\n");
+}
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn setting_defaults_on_and_disabled_sync_keeps_buffer() {
+    let f = Fixture::new();
+    assert!(f.project.settings.effective().files.sync_on_focus);
+    assert!(serde_json::from_value::<ide_core::settings::FileSettings>(serde_json::json!({})).unwrap().sync_on_focus);
+    let original = f.open(&f.outside).await;
+    f.project.settings.set(ide_workspace::settings::SettingsScope::Project, "files.syncOnFocus", false.into()).unwrap();
+    std::fs::write(&f.outside, "external change while disabled\n").unwrap();
+    f.sync().await;
+    assert_eq!(f.project.documents.snapshot(original.id).unwrap().version, original.version);
+    f.project.settings.set(ide_workspace::settings::SettingsScope::Project, "files.syncOnFocus", true.into()).unwrap();
+    f.sync().await;
+    assert_eq!(f.project.documents.snapshot(original.id).unwrap().text, "external change while disabled\n");
+}
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn properties_reload_preserves_native_to_ascii_decoding() {
+    let f = Fixture::new();
+    let path = f.outside.with_extension("properties");
+    std::fs::write(&path, "key=\\u4F60\n").unwrap();
+    let mut defaults = f.project.documents.file_defaults();
+    defaults.native_to_ascii = true;
+    f.project.documents.set_file_defaults(defaults);
+    let original = f.open(&path).await;
+    assert_eq!(original.text, "key=你\n");
+    std::fs::write(&path, "key=\\u4E16\\u754C\n").unwrap();
+    f.sync().await;
+    assert_eq!(f.project.documents.snapshot(original.id).unwrap().text, "key=世界\n");
+}
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn binary_and_virtual_documents_are_skipped() {
+    let f = Fixture::new();
+    let path = f.outside.with_extension("bin");
+    std::fs::write(&path, b"\0\0binary payload").unwrap();
+    let binary = f.open(&path).await;
+    assert!(binary.read_only);
+    let virtual_doc =
+        f.project.documents.open_virtual("test://virtual", ide_core::LanguageId::plain_text(), "virtual").unwrap();
+    std::fs::write(&path, "now ordinary text").unwrap();
+    f.events.lock().clear();
+    f.sync().await;
+    assert_eq!(f.project.documents.snapshot(binary.id).unwrap().version, binary.version);
+    assert_eq!(f.project.documents.snapshot(virtual_doc.id).unwrap().text, "virtual");
+    assert!(f.document_events().is_empty());
+}
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn synchronization_only_changes_the_calling_windows_documents() {
+    let f = Fixture::new();
+    let original = f.open(&f.outside).await;
+    let other_root = f.outside.parent().unwrap().join("other-project");
+    std::fs::create_dir(&other_root).unwrap();
+    let other = f.host.open_project("other", &other_root).unwrap();
+    let other_doc = open(&f.host, "other", f.outside.clone()).await.unwrap();
+    std::fs::write(&f.outside, "external change in shared file\n").unwrap();
+    f.sync().await;
+    assert_eq!(f.project.documents.snapshot(original.id).unwrap().text, "external change in shared file\n");
+    assert_eq!(other.documents.snapshot(other_doc.id).unwrap().text, other_doc.text);
+}
@@ -9,7 +9,7 @@ use std::sync::Arc;
 /// Re-reads the login shell (and the window's project `remoteEnv` where it applies);
 /// running terminals and processes keep their environment.
 pub async fn reload(host: &Arc<Host>, window: &str) -> IdeResult<EnvReloaded> {
-    let root = host.project(window).ok().filter(|p| !p.light).map(|p| p.root.clone());
+    let root = host.project(window).ok().filter(|p| !p.light && p.is_trusted()).map(|p| p.root.clone());
    let sink = host.window_sink(window);
    let h = host.clone();
    host.blocking(move || h.environment.reload(root.as_deref(), &sink)).await
@@ -1,8 +1,73 @@
+use super::Channel;
 use crate::Host;
-use ide_core::IdeResult;
+use ide_core::{IdeResult, RequestId};
 use ide_vfs::FileEntry;
 use std::path::PathBuf;

+pub async fn entry_kind(host: &Host, path: PathBuf) -> IdeResult<ide_vfs::EntryKind> {
+    host.blocking(move || {
+        let meta = std::fs::metadata(path)?;
+        Ok(if meta.is_dir() { ide_vfs::EntryKind::Dir } else { ide_vfs::EntryKind::File })
+    })
+    .await
+}
+
+pub async fn compare_directories(
+    host: &Host,
+    window: &str,
+    left: PathBuf,
+    right: PathBuf,
+    request: RequestId,
+    on_progress: Channel<ide_vfs::DirectoryCompareProgress>,
+) -> IdeResult<Vec<ide_vfs::DirectoryCompareEntry>> {
+    let project = host.project(window)?;
+    let cancel = host.begin_request(request);
+    let result = host
+        .blocking(move || {
+            let last = std::cell::Cell::new(std::time::Instant::now() - std::time::Duration::from_secs(1));
+            ide_vfs::compare_directories(&left, &right, Some(&project.root), &project.exclude_globs(), &cancel, |p| {
+                // Bound IPC traffic even when hashing multi-gigabyte files.
+                if last.get().elapsed() >= std::time::Duration::from_millis(80) || p.total == Some(p.compared) {
+                    let _ = on_progress.send(p);
+                    last.set(std::time::Instant::now());
+                }
+            })
+        })
+        .await;
+    host.end_request(request);
+    result
+}
+
+pub async fn copy_merge(
+    host: &Host,
+    window: &str,
+    source_root: PathBuf,
+    destination_root: PathBuf,
+    path: PathBuf,
+    overwrite: bool,
+) -> IdeResult<()> {
+    if path.as_os_str().is_empty() || path.components().any(|c| !matches!(c, std::path::Component::Normal(_))) {
+        return Err(ide_core::IdeError::invalid("expected a relative comparison entry path"));
+    }
+    let project = host.project(window)?;
+    host.blocking(move || {
+        let from = source_root.join(&path);
+        let to = destination_root.join(&path);
+        if overwrite {
+            project.history.record_deletion(&to, DELETE_SNAPSHOT_LIMIT);
+        }
+        ide_vfs::copy_merge(
+            &from,
+            &to,
+            overwrite,
+            Some(&project.root),
+            &project.exclude_globs(),
+            (&source_root, &destination_root),
+        )
+    })
+    .await
+}
+
 /// Files of a deleted folder snapshotted in Local History.
 const DELETE_SNAPSHOT_LIMIT: usize = 2000;

@@ -49,6 +114,10 @@ pub fn create_file(host: &Host, window: &str, path: PathBuf) -> IdeResult<()> {
    }
 }

+pub async fn create_file_bytes(host: &Host, path: PathBuf, data: Vec<u8>) -> IdeResult<()> {
+    host.blocking(move || ide_vfs::create_file_bytes(&path, &data)).await
+}
+
 /// Toggle Read-only Attribute: sets the writable bit (and the open document's
 /// state). Returns whether the file is read-only now.
 pub fn set_writable(host: &Host, window: &str, path: PathBuf, writable: bool) -> IdeResult<bool> {
@@ -1,13 +1,16 @@
 //! Java launch support: classpath / JDK resolution and the java-debug server (jdtls).
+pub(crate) mod cache;
+
 use crate::Host;
 use crate::rpc::Dispatcher;

 use super::build::load;
 use ide_build::compile;
-use ide_core::{CancellationToken, IdeError, IdeResult};
-use ide_lsp::jdtls::JavaLaunchInfo;
+use ide_core::{CancellationToken, IdeError, IdeResult, RequestId};
+use ide_lsp::jdtls::{JavaBuildStatus, JavaLaunchInfo};
 use std::path::PathBuf;

+/// Cancellable with `cancel_request(request)`.
 /// Builds the workspace (when `build`), then resolves the runtime (or test)
 /// classpath and the JDK of the module at `module` (absolute, or relative to the project root).
 /// A module with Kotlin / Groovy / Scala sources is built by its build system, whose class directories come first.
@@ -17,58 +20,140 @@ pub async fn java_resolve_launch(
    module: PathBuf,
    test: bool,
    build: bool,
+    request: RequestId,
 ) -> IdeResult<JavaLaunchInfo> {
+    host.require_trust(window)?;
+    let cancel = host.begin_project_request(window, request);
+    let result = resolve_launch(host, window, module, test, build, &cancel).await;
+    host.end_request(request);
+    result
+}
+
+async fn resolve_launch(
+    host: &Host,
+    window: &str,
+    module: PathBuf,
+    test: bool,
+    build: bool,
+    cancel: &CancellationToken,
+) -> IdeResult<JavaLaunchInfo> {
+    let started = std::time::Instant::now();
    let project = host.project(window)?;
    let module = project.root.join(module);
    let settings = project.settings.effective();
-    let built = if build && compile::has_non_java_sources(&module) {
-        let (root, cache, module, settings) =
-            (project.root.clone(), project.build_cache_dir(), module.clone(), settings.clone());
+    let (model, external, delegated) = {
+        let project = project.clone();
+        let settings = settings.clone();
+        let module = module.clone();
        tokio::task::spawn_blocking(move || {
-            compile::build_for_launch(&root, &load(&root, &cache, &settings), &module, test, &CancellationToken::new())
+            project.java_launch_snapshots.lock().initialize();
+            let model = load(&project.root, &project.build_cache_dir(), &settings);
+            let non_java = build && compile::launch_has_non_java_sources(&project.root, &model, &module, test);
+            let delegated = build
+                && model.maven.as_ref().is_some_and(|m| m.projects.iter().any(|p| project.root.join(&p.dir) == module))
+                && (non_java || cache::has_record(&project.root, &project.build_cache_dir(), &module));
+            let external = non_java || delegated;
+            (model, external, delegated)
        })
        .await
-        .map_err(|e| IdeError::internal(e.to_string()))??
-    } else {
-        Vec::new()
+        .map_err(|e| IdeError::internal(e.to_string()))?
    };
-    let mut info = project.lsp.java_launch(&module, test, build).await?;
-    let mut class_paths: Vec<String> = built.iter().map(|p| p.to_string_lossy().into_owned()).collect();
-    for p in std::mem::take(&mut info.class_paths) {
-        if !class_paths.contains(&p) {
-            class_paths.push(p);
+    let external_build = if delegated { Some(project.lsp.java_external_build(&module, cancel).await?) } else { None };
+    let mut info = project.lsp.java_launch(&module, test, build && !delegated, cancel).await?;
+    let lsp_ms = started.elapsed().as_millis();
+    let data_dir = host.data_dir.clone();
+    let cancel = cancel.clone();
+    tokio::task::spawn_blocking(move || {
+        let _external_build = external_build;
+        let built = if delegated {
+            let outputs = project.java_launch_snapshots.lock().build(
+                &project.root,
+                &model,
+                &module,
+                test,
+                ide_sdk::apply::maven_local_repository(&project.root, &settings),
+                &cancel,
+            )?;
+            let copies = use_snapshot(&mut info, &outputs.originals, &outputs.snapshot);
+            info.build = Some(JavaBuildStatus::Succeeded);
+            info.errors.clear();
+            info.error_count = 0;
+            copies
+        } else if external {
+            compile::build_for_launch(&project.root, &model, &module, test, &cancel)?
+        } else {
+            Vec::new()
+        };
+        let mut class_paths: Vec<String> = built.iter().map(|p| p.to_string_lossy().into_owned()).collect();
+        for p in std::mem::take(&mut info.class_paths) {
+            if !class_paths.contains(&p) {
+                class_paths.push(p);
+            }
+        }
+        info.class_paths = class_paths;
+        let compile_ms = started.elapsed().as_millis() - lsp_ms;
+        // The project JDK, else the JDK jdtls compiles the module against, else one matching its Java version.
+        let project_jdk = ide_sdk::apply::project_jdk(&project.root, &settings);
+        let from_jdtls = info.java_home.as_deref().map(ide_sdk::java::java_executable).filter(|p| p.is_file());
+        let java = project_jdk.map(|j| ide_sdk::java::java_executable(&j.home)).or(from_jdtls).or_else(|| {
+            let release = ide_sdk::java::project_java_version(&module);
+            let jdks = ide_sdk::java::installed_jdks();
+            info.hints.extend(ide_sdk::java::missing_jdk_message(&jdks, release));
+            ide_sdk::java::pick_jdk(&jdks, release).map(|j| ide_sdk::java::java_executable(&j.home))
+        });
+        info.java_exec = Some(java.map(|p| p.to_string_lossy().into_owned()).unwrap_or_else(|| "java".to_owned()));
+        let exec = PathBuf::from(info.java_exec.as_deref().unwrap_or("java"));
+        let shorten =
+            ide_run::java_cmdline::shortening_for(&exec, &info.class_paths, &info.module_paths, cfg!(windows));
+        info.shorten_command_line = Some(shorten.as_str().to_owned());
+        if info.error_count > 0 {
+            let own = ide_sdk::lombok::agent_in_args(settings.languages.java.jdtls_vm_args.split_whitespace());
+            let managed = ide_tools::managed_bundle(&data_dir, "lombok");
+            let repo = ide_sdk::apply::maven_local_repository(&project.root, &settings);
+            let root = project.root.clone();
+            // Detection may read the project's sources.
+            let lombok = ide_sdk::lombok::lombok_agent(&root, own, managed, repo);
+            info.hints.extend(lombok.problem());
+        }
+        if cancel.is_cancelled() {
+            return Err(IdeError::cancelled());
+        }
+        tracing::info!(
+            lsp_ms,
+            compile_ms,
+            jdk_ms = started.elapsed().as_millis() - lsp_ms - compile_ms,
+            total_ms = started.elapsed().as_millis(),
+            "Java launch resolved"
+        );
+        Ok(info)
+    })
+    .await
+    .map_err(|e| IdeError::internal(e.to_string()))?
+}
+
+fn use_snapshot(info: &mut JavaLaunchInfo, built: &[PathBuf], snapshot: &std::path::Path) -> Vec<PathBuf> {
+    let mut copies = Vec::new();
+    for (index, source) in built.iter().enumerate() {
+        let dest = snapshot.join(index.to_string());
+        let original = source.to_string_lossy();
+        info.class_paths.retain(|p| p != original.as_ref());
+        let mut modular = false;
+        for path in &mut info.module_paths {
+            if path == original.as_ref() {
+                *path = dest.to_string_lossy().into_owned();
+                modular = true;
+            }
+        }
+        if !modular {
+            copies.push(dest);
        }
    }
-    info.class_paths = class_paths;
-    // The project JDK, else the JDK jdtls compiles the module against, else one matching its Java version.
-    let project_jdk = ide_sdk::apply::project_jdk(&project.root, &settings);
-    let from_jdtls = info.java_home.as_deref().map(ide_sdk::java::java_executable).filter(|p| p.is_file());
-    let java = project_jdk.map(|j| ide_sdk::java::java_executable(&j.home)).or(from_jdtls).or_else(|| {
-        let release = ide_sdk::java::project_java_version(&module);
-        let jdks = ide_sdk::java::installed_jdks();
-        info.hints.extend(ide_sdk::java::missing_jdk_message(&jdks, release));
-        ide_sdk::java::pick_jdk(&jdks, release).map(|j| ide_sdk::java::java_executable(&j.home))
-    });
-    info.java_exec = Some(java.map(|p| p.to_string_lossy().into_owned()).unwrap_or_else(|| "java".to_owned()));
-    let exec = PathBuf::from(info.java_exec.as_deref().unwrap_or("java"));
-    let shorten = ide_run::java_cmdline::shortening_for(&exec, &info.class_paths, &info.module_paths, cfg!(windows));
-    info.shorten_command_line = Some(shorten.as_str().to_owned());
-    if info.error_count > 0 {
-        let own = ide_sdk::lombok::agent_in_args(settings.languages.java.jdtls_vm_args.split_whitespace());
-        let managed = ide_tools::managed_bundle(&host.data_dir, "lombok");
-        let repo = ide_sdk::apply::maven_local_repository(&project.root, &settings);
-        let root = project.root.clone();
-        // Detection may read the project's sources.
-        let lombok = tokio::task::spawn_blocking(move || ide_sdk::lombok::lombok_agent(&root, own, managed, repo))
-            .await
-            .map_err(|e| IdeError::internal(e.to_string()))?;
-        info.hints.extend(lombok.problem());
-    }
-    Ok(info)
+    copies
 }

 /// Port of java-debug's DAP server inside the jdtls serving `module` (started on demand).
 pub async fn java_debug_server(host: &Host, window: &str, module: PathBuf) -> IdeResult<u16> {
+    host.require_trust(window)?;
    let project = host.project(window)?;
    let module = project.root.join(module);
    project.lsp.java_debug_server(&module).await
@@ -80,16 +165,55 @@ pub async fn java_build_workspace(
    window: &str,
    module: PathBuf,
 ) -> IdeResult<ide_lsp::jdtls::JavaBuildStatus> {
+    host.require_trust(window)?;
    let project = host.project(window)?;
    let module = project.root.join(module);
-    project.lsp.java_build(&module).await
+    project.lsp.java_build(&module, &CancellationToken::new()).await
 }

 /// Commands of this module the remote server answers.
 pub(crate) fn register(d: &mut Dispatcher) {
    d.add("java_resolve_launch", |c| async move {
-        java_resolve_launch(&c.host, &c.window, c.arg("module")?, c.arg("test")?, c.arg("build")?).await
+        java_resolve_launch(&c.host, &c.window, c.arg("module")?, c.arg("test")?, c.arg("build")?, c.arg("request")?)
+            .await
    });
    d.add("java_debug_server", |c| async move { java_debug_server(&c.host, &c.window, c.arg("module")?).await });
    d.add("java_build_workspace", |c| async move { java_build_workspace(&c.host, &c.window, c.arg("module")?).await });
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn launch_snapshots_survive_jdt_overwrites_and_replace_module_outputs() {
+        let root = tempfile::tempdir().unwrap();
+        let app = root.path().join("app/target/classes");
+        let lib = root.path().join("lib/target/classes");
+        for dir in [&app, &lib] {
+            std::fs::create_dir_all(dir).unwrap();
+            std::fs::write(dir.join("Channel.class"), "Maven bytecode").unwrap();
+        }
+        let mut info = JavaLaunchInfo {
+            class_paths: vec![app.to_string_lossy().into_owned(), "stdlib.jar".into()],
+            module_paths: vec![lib.to_string_lossy().into_owned()],
+            ..Default::default()
+        };
+        let snapshot = tempfile::tempdir().unwrap();
+        for (i, source) in [&app, &lib].iter().enumerate() {
+            ide_vfs::copy(source, &snapshot.path().join(i.to_string())).unwrap();
+        }
+        let paths = use_snapshot(&mut info, &[app.clone(), lib.clone()], snapshot.path());
+        assert_eq!(paths, [snapshot.path().join("0")]);
+        assert_eq!(info.class_paths, ["stdlib.jar"]);
+        assert_eq!(info.module_paths, [snapshot.path().join("1").to_string_lossy().into_owned()]);
+        std::fs::write(app.join("Channel.class"), "JDT error stub").unwrap();
+        std::fs::remove_dir_all(lib).unwrap();
+        for index in ["0", "1"] {
+            assert_eq!(
+                std::fs::read_to_string(snapshot.path().join(index).join("Channel.class")).unwrap(),
+                "Maven bytecode"
+            );
+        }
+    }
+}
@@ -0,0 +1,371 @@
+//! Immutable Maven outputs retained in the project cache, including across close/reopen.
+use ide_build::compile::{self, LaunchFingerprint};
+use ide_core::{CancellationToken, IdeError, IdeResult};
+use serde::{Deserialize, Serialize};
+use std::collections::HashSet;
+use std::fs;
+use std::path::{Path, PathBuf};
+
+#[derive(Debug, Serialize, Deserialize)]
+pub(super) struct Outputs {
+    fingerprint: Option<LaunchFingerprint>,
+    pub snapshot: PathBuf,
+    pub originals: Vec<PathBuf>,
+}
+
+impl Outputs {
+    fn reusable(&self, fingerprint: &Option<LaunchFingerprint>, snapshots: &Path) -> bool {
+        fingerprint.is_some()
+            && self.fingerprint == *fingerprint
+            && self.snapshot.parent() == Some(snapshots)
+            && !self.originals.is_empty()
+            && (0..self.originals.len()).all(|i| self.snapshot.join(i.to_string()).is_dir())
+    }
+}
+
+fn record_path(root: &Path, cache: &Path, module: &Path, test: bool) -> Option<PathBuf> {
+    Some(cache.join("java-launch/records").join(module.strip_prefix(root).ok()?).join(if test {
+        "test.json"
+    } else {
+        "main.json"
+    }))
+}
+
+pub(super) fn has_record(root: &Path, cache: &Path, module: &Path) -> bool {
+    [false, true].into_iter().any(|test| record_path(root, cache, module, test).is_some_and(|record| record.is_file()))
+}
+
+/// Owned by Project: running JVMs may still load superseded outputs until it drops.
+pub(crate) struct Session {
+    cache: PathBuf,
+    initialized: bool,
+    unreferenced: Vec<PathBuf>,
+}
+
+impl Session {
+    pub(crate) fn new(cache: PathBuf) -> Self {
+        Self { cache, initialized: false, unreferenced: Vec::new() }
+    }
+
+    pub(super) fn initialize(&mut self) {
+        if !self.initialized {
+            self.initialized = true;
+            if let Err(error) = sweep(&self.cache) {
+                tracing::warn!(%error, "Cannot clean previous Java launch snapshots");
+            }
+        }
+    }
+
+    pub(super) fn build(
+        &mut self,
+        root: &Path,
+        model: &ide_build::BuildModel,
+        module: &Path,
+        test: bool,
+        local_repo: Option<PathBuf>,
+        cancel: &CancellationToken,
+    ) -> IdeResult<Outputs> {
+        self.initialize();
+        let cache = &self.cache;
+        let record =
+            record_path(root, cache, module, test).ok_or_else(|| IdeError::internal("launch outside project"))?;
+        let snapshots = cache.join("java-launch/snapshots");
+        let fingerprint = || match compile::launch_fingerprint(root, model, module, test, local_repo.clone(), cancel) {
+            Ok(value) => Ok(value),
+            Err(e) if cancel.is_cancelled() => Err(e),
+            Err(e) => {
+                tracing::debug!(error = %e, "Cannot fingerprint Maven launch; rebuilding");
+                Ok(None)
+            }
+        };
+        let before = fingerprint()?;
+        let previous = fs::read(&record).ok().and_then(|bytes| serde_json::from_slice::<Outputs>(&bytes).ok());
+        if let Some(outputs) = previous.as_ref()
+            && outputs.reusable(&before, &snapshots)
+        {
+            tracing::info!(module = %module.display(), test, "Reusing Maven launch snapshot");
+            return Ok(previous.unwrap());
+        }
+        // Retain a non-reusable record even on failure, so removing the final mixed
+        // source still delegates to Maven to clean its old classes on the next launch.
+        fs::create_dir_all(record.parent().unwrap())?;
+        fs::write(&record, b"null")?;
+        if let Some(previous) = previous {
+            self.unreferenced.push(previous.snapshot);
+        }
+        let originals = compile::build_for_launch(root, model, module, test, cancel)?;
+        fs::create_dir_all(&snapshots)?;
+        let snapshot = tempfile::Builder::new().prefix("launch-").tempdir_in(&snapshots)?.keep();
+        // Retain every new snapshot even if copying or publishing its record fails.
+        self.unreferenced.push(snapshot.clone());
+        for (i, source) in originals.iter().enumerate() {
+            if cancel.is_cancelled() {
+                return Err(IdeError::cancelled());
+            }
+            ide_vfs::copy(source, &snapshot.join(i.to_string()))?;
+        }
+        let after = fingerprint()?;
+        if cancel.is_cancelled() {
+            return Err(IdeError::cancelled());
+        }
+        let mut outputs = Outputs { fingerprint: None, snapshot, originals };
+        if before.is_some() && before == after {
+            outputs.fingerprint = before;
+            fs::create_dir_all(record.parent().unwrap())?;
+            let mut file = tempfile::NamedTempFile::new_in(record.parent().unwrap())?;
+            serde_json::to_writer(file.as_file_mut(), &outputs).map_err(|e| IdeError::internal(e.to_string()))?;
+            file.persist(&record).map_err(|e| IdeError::from(e.error))?;
+            self.unreferenced.retain(|path| path != &outputs.snapshot);
+        }
+        Ok(outputs)
+    }
+}
+
+impl Drop for Session {
+    fn drop(&mut self) {
+        // Recheck all records: another module or launch mode may reference a path.
+        if let Ok(referenced) = referenced_snapshots(&self.cache) {
+            let snapshots = self.cache.join("java-launch/snapshots");
+            for path in &self.unreferenced {
+                remove_unreferenced(path, &snapshots, &referenced);
+            }
+        }
+    }
+}
+
+fn referenced_snapshots(cache: &Path) -> std::io::Result<HashSet<PathBuf>> {
+    let mut referenced = HashSet::new();
+    let records = cache.join("java-launch/records");
+    if !records.try_exists()? {
+        return Ok(referenced);
+    }
+    let mut pending = vec![records];
+    while let Some(dir) = pending.pop() {
+        for entry in fs::read_dir(dir)? {
+            let entry = entry?;
+            let kind = entry.file_type()?;
+            if kind.is_dir() {
+                pending.push(entry.path());
+            } else if kind.is_file() && entry.path().extension().is_some_and(|ext| ext == "json") {
+                let outputs: Option<Outputs> = serde_json::from_slice(&fs::read(entry.path())?)?;
+                if let Some(outputs) = outputs
+                    && let Ok(path) = fs::canonicalize(outputs.snapshot)
+                {
+                    referenced.insert(path);
+                }
+            }
+        }
+    }
+    Ok(referenced)
+}
+
+fn remove_unreferenced(path: &Path, snapshots: &Path, referenced: &HashSet<PathBuf>) {
+    // Only real launch-* directories directly inside snapshots, never symlinks.
+    if path.parent() != Some(snapshots)
+        || !path.file_name().is_some_and(|name| name.to_string_lossy().starts_with("launch-"))
+        || !fs::symlink_metadata(path).is_ok_and(|meta| meta.file_type().is_dir())
+    {
+        return;
+    }
+    if let (Ok(path), Ok(snapshots)) = (fs::canonicalize(path), fs::canonicalize(snapshots))
+        && path.parent() == Some(snapshots.as_path())
+        && !referenced.contains(&path)
+        && let Err(error) = fs::remove_dir_all(&path)
+    {
+        tracing::warn!(%error, path = %path.display(), "Cannot remove Java launch snapshot");
+    }
+}
+
+fn sweep(cache: &Path) -> std::io::Result<()> {
+    let referenced = referenced_snapshots(cache)?;
+    let snapshots = cache.join("java-launch/snapshots");
+    if snapshots.try_exists()? {
+        for entry in fs::read_dir(&snapshots)? {
+            remove_unreferenced(&entry?.path(), &snapshots, &referenced);
+        }
+    }
+    Ok(())
+}
+
+#[cfg(all(test, unix))]
+mod tests {
+    use super::*;
+    use std::os::unix::fs::PermissionsExt;
+
+    fn fixture(root: &Path) -> ide_build::BuildModel {
+        fs::write(
+            root.join("pom.xml"),
+            r#"<project><groupId>demo</groupId><artifactId>app</artifactId><version>1</version></project>"#,
+        )
+        .unwrap();
+        let script = root.join("mvnw");
+        fs::write(&script, "#!/bin/sh\necho build >> calls\nif [ -f src/main/kotlin/broken ]; then exit 1; fi\nmkdir -p target/classes\ncp src/main/kotlin/Main.kt target/classes/Main.class\n").unwrap();
+        fs::set_permissions(&script, fs::Permissions::from_mode(0o755)).unwrap();
+        fs::create_dir_all(root.join("src/main/kotlin")).unwrap();
+        fs::write(root.join("src/main/kotlin/Main.kt"), "first").unwrap();
+        ide_build::load(root, &root.join("cache"), None)
+    }
+
+    #[test]
+    fn successful_snapshots_reuse_across_close_and_rebuild_for_changes_missing_outputs_or_failure() {
+        let dir = tempfile::tempdir().unwrap();
+        let root = dir.path();
+        let model = fixture(root);
+        let cache = root.join("cache");
+        let cancel = CancellationToken::new();
+        let mut session = Session::new(cache.clone());
+        let mut build = || session.build(root, &model, root, false, None, &cancel);
+        let first = build().unwrap();
+        let snapshot = first.snapshot.clone();
+        drop(first);
+        // Dropping an Outputs value leaves the persisted snapshot reusable.
+        let second = build().unwrap();
+        assert_eq!(snapshot, second.snapshot);
+        assert_eq!(fs::read_to_string(root.join("calls")).unwrap().lines().count(), 1);
+        fs::write(root.join("target/classes/Main.class"), "JDT stub").unwrap();
+        assert_eq!(snapshot, build().unwrap().snapshot);
+        assert_eq!(fs::read_to_string(snapshot.join("0/Main.class")).unwrap(), "first");
+        fs::write(root.join("src/main/kotlin/Main.kt"), "updated").unwrap();
+        let updated = build().unwrap();
+        assert_ne!(snapshot, updated.snapshot);
+        assert_eq!(fs::read_to_string(updated.snapshot.join("0/Main.class")).unwrap(), "updated");
+        assert!(snapshot.join("0/Main.class").is_file(), "previous JVMs may still load it");
+        fs::remove_dir_all(updated.snapshot.join("0")).unwrap();
+        let rebuilt = build().unwrap();
+        assert_ne!(rebuilt.snapshot, updated.snapshot);
+        fs::write(root.join("src/main/kotlin/broken"), "broken").unwrap();
+        assert!(build().is_err());
+        assert_eq!(fs::read(cache.join("java-launch/records/main.json")).unwrap(), b"null");
+        fs::remove_file(root.join("src/main/kotlin/broken")).unwrap();
+        assert_ne!(rebuilt.snapshot, build().unwrap().snapshot, "a failed build invalidates success");
+        cancel.cancel();
+        assert!(build().is_err());
+        assert_eq!(fs::read_to_string(root.join("calls")).unwrap().lines().count(), 5);
+    }
+    #[test]
+    fn session_drop_removes_superseded_snapshots_and_preserves_records_across_reopen() {
+        let dir = tempfile::tempdir().unwrap();
+        let root = dir.path();
+        let model = fixture(root);
+        let cache = root.join("cache");
+        let cancel = CancellationToken::new();
+        let mut session = Session::new(cache.clone());
+        let first = session.build(root, &model, root, false, None, &cancel).unwrap();
+        fs::write(root.join("src/main/kotlin/Main.kt"), "updated").unwrap();
+        let second = session.build(root, &model, root, false, None, &cancel).unwrap();
+        assert!(first.snapshot.is_dir());
+        assert!(second.snapshot.is_dir());
+        // Another mode can keep a superseded snapshot alive.
+        let test_record = cache.join("java-launch/records/nested/test.json");
+        fs::create_dir_all(test_record.parent().unwrap()).unwrap();
+        fs::write(&test_record, serde_json::to_vec(&first).unwrap()).unwrap();
+        drop(session);
+        assert!(first.snapshot.is_dir());
+        assert!(second.snapshot.is_dir());
+        let mut session = Session::new(cache.clone());
+        let reused = session.build(root, &model, root, false, None, &cancel).unwrap();
+        assert_eq!(reused.snapshot, second.snapshot);
+        fs::write(root.join("src/main/kotlin/Main.kt"), "third version").unwrap();
+        let third = session.build(root, &model, root, false, None, &cancel).unwrap();
+        assert!(second.snapshot.is_dir());
+        drop(session);
+        assert!(!second.snapshot.exists());
+        assert!(first.snapshot.is_dir());
+        assert!(third.snapshot.is_dir());
+        assert_eq!(fs::read_to_string(root.join("calls")).unwrap().lines().count(), 3);
+    }
+
+    #[test]
+    fn initial_sweep_only_removes_unreferenced_direct_snapshot_directories() {
+        let dir = tempfile::tempdir().unwrap();
+        let cache = dir.path().join("cache");
+        let snapshots = cache.join("java-launch/snapshots");
+        let retained = snapshots.join("launch-retained");
+        let orphan = snapshots.join("launch-orphan");
+        let other = snapshots.join("other");
+        let nested = other.join("launch-nested");
+        let outside = dir.path().join("launch-outside");
+        for path in [&retained, &orphan, &nested, &outside] {
+            fs::create_dir_all(path).unwrap();
+        }
+        fs::write(outside.join("classes"), "keep").unwrap();
+        std::os::unix::fs::symlink(&outside, snapshots.join("launch-link")).unwrap();
+        fs::write(snapshots.join("launch-file"), "keep").unwrap();
+        let record = cache.join("java-launch/records/deep/module/test.json");
+        fs::create_dir_all(record.parent().unwrap()).unwrap();
+        let outputs = Outputs { fingerprint: None, snapshot: retained.clone(), originals: Vec::new() };
+        fs::write(record, serde_json::to_vec(&outputs).unwrap()).unwrap();
+        let mut session = Session::new(cache);
+        session.initialize();
+        assert!(!orphan.exists());
+        assert!(retained.is_dir());
+        assert!(nested.is_dir());
+        assert!(outside.join("classes").is_file());
+        assert!(snapshots.join("launch-link").is_symlink());
+        assert!(snapshots.join("launch-file").is_file());
+        // Initialization must not sweep snapshots still in use by this session.
+        fs::create_dir_all(&orphan).unwrap();
+        session.initialize();
+        assert!(orphan.is_dir());
+        session.unreferenced.extend([outside.clone(), snapshots.join("../../launch-outside"), nested]);
+        drop(session);
+        assert!(outside.join("classes").is_file());
+        assert!(other.join("launch-nested").is_dir());
+    }
+
+    #[test]
+    fn failed_record_publish_retains_snapshot_until_session_drop() {
+        let dir = tempfile::tempdir().unwrap();
+        let root = dir.path();
+        let model = fixture(root);
+        let script = root.join("mvnw");
+        let mut text = fs::read_to_string(&script).unwrap();
+        text.push_str("rm cache/java-launch/records/main.json\nmkdir cache/java-launch/records/main.json\n");
+        fs::write(script, text).unwrap();
+        let cache = root.join("cache");
+        let mut session = Session::new(cache.clone());
+        assert!(session.build(root, &model, root, false, None, &CancellationToken::new()).is_err());
+        assert_eq!(session.unreferenced.len(), 1);
+        let snapshot = session.unreferenced[0].clone();
+        assert!(snapshot.join("0/Main.class").is_file());
+        drop(session);
+        assert!(!snapshot.exists());
+    }
+
+    #[test]
+    fn edits_during_build_do_not_publish_a_success_record() {
+        let dir = tempfile::tempdir().unwrap();
+        let root = dir.path();
+        let model = fixture(root);
+        let script = root.join("mvnw");
+        let mut text = fs::read_to_string(&script).unwrap();
+        text.push_str("echo edited-during-build >> src/main/kotlin/Main.kt\n");
+        fs::write(script, text).unwrap();
+        let cache = root.join("cache");
+        let mut session = Session::new(cache.clone());
+        let outputs = session.build(root, &model, root, false, None, &CancellationToken::new()).unwrap();
+        assert!(outputs.fingerprint.is_none());
+        assert_eq!(fs::read(cache.join("java-launch/records/main.json")).unwrap(), b"null");
+        assert!(outputs.snapshot.join("0/Main.class").is_file());
+        drop(session);
+        assert!(!outputs.snapshot.exists());
+    }
+    #[test]
+    fn deleting_the_last_mixed_source_keeps_maven_delegation_after_failure() {
+        let dir = tempfile::tempdir().unwrap();
+        let root = dir.path();
+        let model = fixture(root);
+        let cache = root.join("cache");
+        let cancel = CancellationToken::new();
+        let mut session = Session::new(cache.clone());
+        let first = session.build(root, &model, root, false, None, &cancel).unwrap();
+        fs::remove_file(root.join("src/main/kotlin/Main.kt")).unwrap();
+        assert!(!compile::launch_has_non_java_sources(root, &model, root, false));
+        assert!(has_record(root, &cache, root));
+        assert!(session.build(root, &model, root, false, None, &cancel).is_err());
+        assert!(has_record(root, &cache, root));
+        fs::write(root.join("src/main/kotlin/Main.kt"), "restored").unwrap();
+        let restored = session.build(root, &model, root, false, None, &cancel).unwrap();
+        assert_ne!(first.snapshot, restored.snapshot);
+    }
+}
@@ -0,0 +1,102 @@
+//! Bounded, read-only JVM presentation for visible files, also served remotely.
+use crate::Host;
+use ide_core::{CancellationToken, IdeError, IdeResult, LanguageId};
+use ide_syntax::{JvmPresentation, Snapshot};
+use serde::{Deserialize, Serialize};
+use specta::Type;
+use std::{
+    collections::HashMap,
+    fs::File,
+    io::Read,
+    path::PathBuf,
+    sync::{Mutex, OnceLock},
+    time::SystemTime,
+};
+
+pub const PREFIX_BYTES: u64 = 64 * 1024;
+const MAX_BATCH: usize = 64;
+const MAX_CACHE: usize = 4096;
+
+#[derive(Clone, Debug, Serialize, Deserialize, Type)]
+#[serde(rename_all = "camelCase")]
+pub struct JvmFilePresentation {
+    pub path: PathBuf,
+    pub presentation: JvmPresentation,
+}
+
+#[derive(Clone)]
+struct Cached {
+    modified: SystemTime,
+    size: u64,
+    presentation: JvmPresentation,
+}
+
+fn prefix(path: &PathBuf) -> std::io::Result<String> {
+    let mut bytes = Vec::new();
+    File::open(path)?.take(PREFIX_BYTES).read_to_end(&mut bytes)?;
+    // A truncated final UTF-8 character must not invalidate the entire prefix.
+    Ok(String::from_utf8_lossy(&bytes).into_owned())
+}
+
+pub async fn jvm_file_presentations(
+    host: &Host,
+    window: &str,
+    paths: Vec<PathBuf>,
+) -> IdeResult<Vec<JvmFilePresentation>> {
+    if paths.len() > MAX_BATCH {
+        return Err(IdeError::invalid("at most 64 JVM files per batch"));
+    }
+    let project = host.project(window)?;
+    host.blocking(move || {
+        static CACHE: OnceLock<Mutex<HashMap<PathBuf, Cached>>> = OnceLock::new();
+        let cache = CACHE.get_or_init(Default::default);
+        let mut results = Vec::new();
+        for path in paths {
+            let language = match path.extension().and_then(|e| e.to_str()) {
+                Some("java") => LanguageId::new("java"),
+                Some("kt") => LanguageId::new("kotlin"),
+                _ => continue,
+            };
+            let Ok(meta) = path.metadata() else { continue };
+            if !meta.is_file() {
+                continue;
+            }
+            let Ok(modified) = meta.modified() else { continue };
+            let hit =
+                cache.lock().unwrap().get(&path).filter(|c| c.modified == modified && c.size == meta.len()).cloned();
+            let presentation = if let Some(hit) = hit {
+                hit.presentation
+            } else {
+                let Ok(source) = prefix(&path) else { continue };
+                let stem = path.file_stem().and_then(|s| s.to_str()).unwrap_or_default();
+                let presentation = project.structure.jvm_presentation(
+                    &Snapshot::text(&language, &source),
+                    stem,
+                    &CancellationToken::new(),
+                )?;
+                let mut cache = cache.lock().unwrap();
+                if cache.len() >= MAX_CACHE {
+                    cache.clear();
+                }
+                cache.insert(path.clone(), Cached { modified, size: meta.len(), presentation: presentation.clone() });
+                presentation
+            };
+            results.push(JvmFilePresentation { path, presentation });
+        }
+        Ok(results)
+    })
+    .await
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn huge_files_read_only_a_prefix() {
+        let path = std::env::temp_dir().join(format!("openidea-icon-prefix-{}.java", std::process::id()));
+        let file = File::create(&path).unwrap();
+        file.set_len(100 * 1024 * 1024).unwrap();
+        assert_eq!(prefix(&path).unwrap().len(), PREFIX_BYTES as usize);
+        std::fs::remove_file(path).unwrap();
+    }
+}
@@ -83,12 +83,18 @@ pub async fn lsp_implementations(
    result
 }

-/// Contents of a virtual document (library class, decompiled code) that a
-/// language server returned a non-`file:` URI for. Cached per project.
+/// Contents of a read-only language-server document, including JDT library
+/// classes and disk class files. Cached per project.
 pub async fn lsp_virtual_document(host: &Host, window: &str, uri: String) -> IdeResult<VirtualDocument> {
    host.project(window)?.lsp.virtual_document(&uri).await
 }

+/// Opens compiled classes through JDT, with project source taking priority on disk.
+pub async fn lsp_resolve_class_file(host: &Host, window: &str, path: std::path::PathBuf) -> IdeResult<String> {
+    let archive = ide_vfs::split_archive_path(&path);
+    host.project(window)?.lsp.java_class_file(&path, archive).await
+}
+
 /// References of the symbol at `pos`. `project_wide` also searches project files
 /// outside the language server's analysis scope; bulk scans over many symbols
 /// leave it off. Cancel with `cancel_request(request)`.
@@ -186,8 +192,19 @@ pub async fn lsp_prepare_rename(host: &Host, window: &str, doc: DocId, pos: Pos)
 }

 /// Computes the rename edit without applying it, so the UI can preview conflicts.
-pub async fn lsp_rename(host: &Host, window: &str, doc: DocId, pos: Pos, new_name: String) -> IdeResult<WorkspaceEdit> {
-    host.project(window)?.lsp.rename(doc, pos, new_name).await
+pub async fn lsp_rename(
+    host: &Host,
+    window: &str,
+    request: RequestId,
+    doc: DocId,
+    pos: Pos,
+    new_name: String,
+) -> IdeResult<Renamed> {
+    let lsp = host.project(window)?.lsp.clone();
+    let cancel = host.begin_request(request);
+    let result = lsp.rename(doc, pos, new_name, cancel).await;
+    host.end_request(request);
+    result
 }

 pub async fn lsp_format(
@@ -197,7 +214,7 @@ pub async fn lsp_format(
    range: Option<Range>,
    options: FormatOptions,
 ) -> IdeResult<Vec<TextEdit>> {
-    host.project(window)?.lsp.format(doc, range, options).await
+    crate::formatter::format(host, window, doc, range, options).await
 }

 pub async fn lsp_inlay_hints(host: &Host, window: &str, doc: DocId, range: Range) -> IdeResult<Vec<InlayHint>> {
@@ -220,11 +237,16 @@ pub async fn lsp_document_links(host: &Host, window: &str, doc: DocId) -> IdeRes
 pub async fn lsp_call_hierarchy(
    host: &Host,
    window: &str,
+    request: RequestId,
    doc: DocId,
    pos: Pos,
    direction: HierarchyDirection,
-) -> IdeResult<Vec<HierarchyItem>> {
-    host.project(window)?.lsp.call_hierarchy(doc, pos, direction).await
+) -> IdeResult<CallHierarchy> {
+    let lsp = host.project(window)?.lsp.clone();
+    let cancel = host.begin_request(request);
+    let result = lsp.call_hierarchy(doc, pos, direction, cancel).await;
+    host.end_request(request);
+    result
 }

 pub async fn lsp_type_hierarchy(
@@ -247,7 +269,13 @@ pub fn lsp_resend_diagnostics(host: &Host, window: &str) -> IdeResult<()> {
 }

 pub async fn lsp_restart(host: &Host, window: &str, server: ServerId) -> IdeResult<()> {
-    host.project(window)?.lsp.restart(server).await
+    let project = host.project(window)?;
+    let java = project.lsp.servers().iter().any(|s| s.id == server && s.name == "jdtls");
+    project.lsp.restart(server).await?;
+    if java && let Some(bridge) = &project.kotlin_bridge {
+        bridge.schedule();
+    }
+    Ok(())
 }

 /// Applies a (previewed) workspace edit, e.g. after rename confirmation.
@@ -274,6 +302,58 @@ pub async fn lsp_execute_command(host: &Host, window: &str, doc: DocId, command:
    host.project(window)?.lsp.execute_command(doc, command).await
 }

+/// Resolves an interactive command without applying edits or executing it.
+pub async fn lsp_resolve_command(
+    host: &Host,
+    window: &str,
+    request: RequestId,
+    doc: DocId,
+    server: ServerId,
+    command: Command,
+    answers: Vec<FormAnswer>,
+) -> IdeResult<Option<CommandForm>> {
+    let lsp = host.project(window)?.lsp.clone();
+    let cancel = host.begin_request(request);
+    let result = lsp.resolve_command(doc, server, command, answers, cancel).await;
+    host.end_request(request);
+    result
+}
+
+/// Applies an explicitly invoked action after the interactive answers have been validated.
+pub async fn lsp_execute_code_action(
+    host: &Host,
+    window: &str,
+    request: RequestId,
+    doc: DocId,
+    action: CodeAction,
+    answers: Vec<FormAnswer>,
+) -> IdeResult<Vec<ide_core::IpcPath>> {
+    let project = host.project(window)?;
+    let cancel = host.begin_request(request);
+    let result = async {
+        if cancel.is_cancelled() {
+            return Err(ide_core::IdeError::cancelled());
+        }
+        if let Some(edit) = action.edit {
+            let documents = project.documents.clone();
+            tokio::task::spawn_blocking(move || apply_edit(&documents, &edit))
+                .await
+                .map_err(|e| ide_core::IdeError::internal(e.to_string()))??;
+        }
+        match action.command {
+            Some(command) => project
+                .lsp
+                .execute_action_command(doc, action.server, command, answers, cancel)
+                .await
+                .map(|paths| paths.into_iter().map(ide_core::IpcPath::from).collect()),
+            None => Ok(Vec::new()),
+        }
+    }
+    .await;
+    host.end_request(request);
+    result
+}
+
 /// Commands of this module the remote server answers.
 pub(crate) fn register(d: &mut Dispatcher) {
    d.add("lsp_completion", |c| async move {
@@ -299,6 +379,10 @@ pub(crate) fn register(d: &mut Dispatcher) {
    d.add("lsp_implementations", |c| async move {
        lsp_implementations(&c.host, &c.window, c.arg("request")?, c.arg("doc")?, c.arg("positions")?).await
    });
+    d.add(
+        "lsp_resolve_class_file",
+        |c| async move { lsp_resolve_class_file(&c.host, &c.window, c.arg("path")?).await },
+    );
    d.add("lsp_virtual_document", |c| async move { lsp_virtual_document(&c.host, &c.window, c.arg("uri")?).await });
    d.add("lsp_references", |c| async move {
        lsp_references(
@@ -335,7 +419,7 @@ pub(crate) fn register(d: &mut Dispatcher) {
        lsp_prepare_rename(&c.host, &c.window, c.arg("doc")?, c.arg("pos")?).await
    });
    d.add("lsp_rename", |c| async move {
-        lsp_rename(&c.host, &c.window, c.arg("doc")?, c.arg("pos")?, c.arg("newName")?).await
+        lsp_rename(&c.host, &c.window, c.arg("request")?, c.arg("doc")?, c.arg("pos")?, c.arg("newName")?).await
    });
    d.add("lsp_format", |c| async move {
        lsp_format(&c.host, &c.window, c.arg("doc")?, c.arg("range")?, c.arg("options")?).await
@@ -348,7 +432,8 @@ pub(crate) fn register(d: &mut Dispatcher) {
    d.add("lsp_code_lens", |c| async move { lsp_code_lens(&c.host, &c.window, c.arg("doc")?).await });
    d.add("lsp_document_links", |c| async move { lsp_document_links(&c.host, &c.window, c.arg("doc")?).await });
    d.add("lsp_call_hierarchy", |c| async move {
-        lsp_call_hierarchy(&c.host, &c.window, c.arg("doc")?, c.arg("pos")?, c.arg("direction")?).await
+        lsp_call_hierarchy(&c.host, &c.window, c.arg("request")?, c.arg("doc")?, c.arg("pos")?, c.arg("direction")?)
+            .await
    });
    d.add("lsp_type_hierarchy", |c| async move {
        lsp_type_hierarchy(&c.host, &c.window, c.arg("doc")?, c.arg("pos")?, c.arg("direction")?).await
@@ -357,6 +442,29 @@ pub(crate) fn register(d: &mut Dispatcher) {
    d.add("lsp_resend_diagnostics", |c| async move { lsp_resend_diagnostics(&c.host, &c.window) });
    d.add("lsp_restart", |c| async move { lsp_restart(&c.host, &c.window, c.arg("server")?).await });
    d.add("apply_workspace_edit", |c| async move { apply_workspace_edit(&c.host, &c.window, c.arg("edit")?) });
+    d.add("lsp_resolve_command", |c| async move {
+        lsp_resolve_command(
+            &c.host,
+            &c.window,
+            c.arg("request")?,
+            c.arg("doc")?,
+            c.arg("server")?,
+            c.arg("command")?,
+            c.arg("answers")?,
+        )
+        .await
+    });
+    d.add("lsp_execute_code_action", |c| async move {
+        lsp_execute_code_action(
+            &c.host,
+            &c.window,
+            c.arg("request")?,
+            c.arg("doc")?,
+            c.arg("action")?,
+            c.arg("answers")?,
+        )
+        .await
+    });
    d.add("lsp_execute_command", |c| async move {
        lsp_execute_command(&c.host, &c.window, c.arg("doc")?, c.arg("command")?).await
    });
@@ -8,13 +8,16 @@ pub mod build;
 pub mod bytes;
 pub mod coverage;
 pub mod debug;
+pub mod deploy;
 pub mod doc;
 pub mod env;
 pub mod fs;
 pub mod history;
 pub mod java;
+pub mod jvm_icons;
 pub mod lsp;
 pub mod nav;
+pub mod notebook;
 pub mod project;
 mod python;
 pub mod refactor;
@@ -60,6 +63,7 @@ impl<T> Clone for Channel<T> {
 pub fn register_all(d: &mut crate::rpc::Dispatcher) {
    agent::register(d);
    lsp::register(d);
+    notebook::register(d);
    nav::register(d);
    refactor::register(d);
    analysis::register(d);
@@ -78,6 +82,7 @@ pub fn register_all(d: &mut crate::rpc::Dispatcher) {
    search::register(d);
    run::register(d);
    env::register(d);
+    deploy::register(d);
 }

 impl Host {
@@ -0,0 +1,157 @@
+//! Native notebook operations shared by desktop IPC and the remote dispatcher.
+use crate::Host;
+pub use crate::notebook::NotebookOutputEvent;
+use crate::ops::Channel;
+use crate::rpc::Dispatcher;
+use ide_core::{IdeError, IdeResult, RequestId};
+use ide_notebook::{NotebookEdit, NotebookSnapshot};
+use std::path::PathBuf;
+
+pub async fn open(host: &Host, window: &str, path: String) -> IdeResult<NotebookSnapshot> {
+    let project = host.project(window)?;
+    let path = PathBuf::from(path);
+    let path = if path.is_absolute() { path } else { project.root.join(path) };
+    let notebooks = project.notebooks.clone();
+    host.blocking(move || notebooks.open(&path)).await
+}
+
+pub fn get(host: &Host, window: &str, id: String) -> IdeResult<NotebookSnapshot> {
+    host.project(window)?.notebooks.get(&id)
+}
+
+pub async fn edit(
+    host: &Host,
+    window: &str,
+    id: String,
+    version: u32,
+    edit: NotebookEdit,
+) -> IdeResult<NotebookSnapshot> {
+    let notebooks = host.project(window)?.notebooks.clone();
+    host.blocking(move || notebooks.edit(&id, version, edit)).await
+}
+
+pub async fn save(host: &Host, window: &str, id: String) -> IdeResult<NotebookSnapshot> {
+    let notebooks = host.project(window)?.notebooks.clone();
+    host.blocking(move || notebooks.save(&id)).await
+}
+
+pub async fn undo(host: &Host, window: &str, id: String) -> IdeResult<NotebookSnapshot> {
+    let notebooks = host.project(window)?.notebooks.clone();
+    host.blocking(move || notebooks.undo(&id, false)).await
+}
+
+pub async fn redo(host: &Host, window: &str, id: String) -> IdeResult<NotebookSnapshot> {
+    let notebooks = host.project(window)?.notebooks.clone();
+    host.blocking(move || notebooks.undo(&id, true)).await
+}
+
+pub async fn reload(host: &Host, window: &str, id: String) -> IdeResult<NotebookSnapshot> {
+    let notebooks = host.project(window)?.notebooks.clone();
+    // An abandoned IPC future must not leave a lifecycle transition half applied.
+    tokio::spawn(async move { notebooks.reload(&id, false).await })
+        .await
+        .map_err(|error| IdeError::internal(error.to_string()))?
+}
+
+pub async fn restart(host: &Host, window: &str, id: String) -> IdeResult<NotebookSnapshot> {
+    host.require_trust(window)?;
+    let notebooks = host.project(window)?.notebooks.clone();
+    tokio::spawn(async move { notebooks.reload(&id, true).await })
+        .await
+        .map_err(|error| IdeError::internal(error.to_string()))?
+}
+
+pub async fn close(host: &Host, window: &str, id: String) -> IdeResult<()> {
+    let notebooks = host.project(window)?.notebooks.clone();
+    tokio::spawn(async move { notebooks.close(&id).await })
+        .await
+        .map_err(|error| IdeError::internal(error.to_string()))?
+}
+
+pub async fn interrupt(host: &Host, window: &str, id: String) -> IdeResult<()> {
+    let notebooks = host.project(window)?.notebooks.clone();
+    tokio::spawn(async move { notebooks.interrupt(&id).await })
+        .await
+        .map_err(|error| IdeError::internal(error.to_string()))?
+}
+
+#[allow(clippy::too_many_arguments)]
+pub async fn execute(
+    host: &Host,
+    window: &str,
+    id: String,
+    cells: Vec<String>,
+    python: Option<String>,
+    request: RequestId,
+    on_output: Channel<NotebookOutputEvent>,
+) -> IdeResult<NotebookSnapshot> {
+    host.require_trust(window)?;
+    let project = host.project(window)?;
+    let cancel = host.begin_project_request(window, request);
+    let _request = RequestGuard { host, request, cancel: cancel.clone() };
+    // Reserve the WHOLE batch and capture source before asynchronous discovery.
+    let admission = project.notebooks.admit(&id, cells, cancel.clone())?;
+    let selected = match python {
+        Some(path) if path.trim().is_empty() => return Err(IdeError::invalid("select a Python interpreter")),
+        Some(path) => PathBuf::from(path),
+        None => {
+            let root = project.root.clone();
+            let settings = project.settings.effective();
+            tokio::select! {
+                biased;
+                _ = cancel.cancelled() => return Err(IdeError::cancelled()),
+                result = host.blocking(move || {
+                    ide_sdk::apply::python_interpreter(&root, &settings)
+                        .or_else(|| ide_sdk::detect(ide_sdk::SdkKind::Python, Some(&root))
+                            .into_iter().next().map(|sdk| sdk.path.into_path_buf()))
+                        .ok_or_else(|| IdeError::unavailable("select a Python environment with ipykernel installed"))
+                }) => result?,
+            }
+        }
+    };
+    // Do not canonicalize this path: resolving a venv symlink to base Python
+    // changes sys.prefix and executes in the wrong environment.
+    let python = if selected.is_absolute() { selected } else { project.root.join(selected) };
+    project.notebooks.execute(admission, python, on_output).await
+}
+
+struct RequestGuard<'a> {
+    host: &'a Host,
+    request: RequestId,
+    cancel: ide_core::CancellationToken,
+}
+
+impl Drop for RequestGuard<'_> {
+    fn drop(&mut self) {
+        // If the invocation is dropped, the owned batch still receives cancellation.
+        self.cancel.cancel();
+        self.host.end_request(self.request);
+    }
+}
+
+pub(crate) fn register(d: &mut Dispatcher) {
+    d.add("notebook_open", |c| async move { open(&c.host, &c.window, c.arg("path")?).await });
+    d.add("notebook_get", |c| async move { get(&c.host, &c.window, c.arg("id")?) });
+    d.add("notebook_edit", |c| async move {
+        edit(&c.host, &c.window, c.arg("id")?, c.arg("version")?, c.arg("edit")?).await
+    });
+    d.add("notebook_save", |c| async move { save(&c.host, &c.window, c.arg("id")?).await });
+    d.add("notebook_reload", |c| async move { reload(&c.host, &c.window, c.arg("id")?).await });
+    d.add("notebook_undo", |c| async move { undo(&c.host, &c.window, c.arg("id")?).await });
+    d.add("notebook_redo", |c| async move { redo(&c.host, &c.window, c.arg("id")?).await });
+    d.add("notebook_close", |c| async move { close(&c.host, &c.window, c.arg("id")?).await });
+    d.add("notebook_interrupt", |c| async move { interrupt(&c.host, &c.window, c.arg("id")?).await });
+    d.add("notebook_restart", |c| async move { restart(&c.host, &c.window, c.arg("id")?).await });
+    d.add("notebook_execute", |c| async move {
+        execute(
+            &c.host,
+            &c.window,
+            c.arg("id")?,
+            c.arg("cells")?,
+            c.arg("python")?,
+            c.arg("request")?,
+            c.sender("onOutput")?,
+        )
+        .await
+    });
+}
@@ -10,16 +10,20 @@ use std::sync::Arc;
 #[derive(Serialize, Deserialize, Type)]
 #[serde(rename_all = "camelCase")]
 pub struct ProjectInfo {
+    pub trusted: bool,
    pub root: ide_core::IpcPath,
    pub name: String,
    pub is_git: bool,
    pub settings: Settings,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub workspace: Option<ide_workspace::workspace::Workspace>,
 }

 pub fn info(project: &Project) -> ProjectInfo {
    let settings = project.settings.effective();
    let custom = settings.general.project_name.trim();
    ProjectInfo {
+        trusted: project.is_trusted(),
        name: if custom.is_empty() {
            project.root.file_name().map(|n| n.to_string_lossy().into_owned()).unwrap_or_default()
        } else {
@@ -28,6 +32,7 @@ pub fn info(project: &Project) -> ProjectInfo {
        is_git: !project.repos.read().is_empty(),
        settings,
        root: project.root.clone().into(),
+        workspace: ide_workspace::workspace::Workspace::load(&project.root).ok().flatten(),
    }
 }

@@ -53,6 +58,42 @@ pub fn roots(host: &Host, window: &str) -> IdeResult<ide_workspace::ProjectRoots
    Ok(host.project(window)?.roots())
 }

+pub fn save_workspace(host: &Host, window: &str, name: &str, paths: Vec<std::path::PathBuf>) -> IdeResult<ProjectInfo> {
+    let project = host.project(window)?;
+    ide_workspace::workspace::Workspace::save(&project.root, name, paths, false)?;
+    project.settings.reload();
+    project.refresh_index_scope();
+    project.refresh_repositories();
+    project.sink.emit(ide_core::IdeEvent::ProjectRootsChanged { root: project.root.clone().into() });
+    Ok(info(&project))
+}
+
+/// Links a folder, or prepares an automatic workspace for the caller to open in place.
+pub fn attach_workspace(host: &Host, window: &str, path: &Path) -> IdeResult<ide_core::IpcPath> {
+    let project = host.project(window)?;
+    let path = dunce::canonicalize(path)?;
+    if project.light {
+        return Err(ide_core::IdeError::invalid("Open a project before attaching a folder"));
+    }
+    if let Some(mut workspace) = ide_workspace::workspace::Workspace::load(&project.root)? {
+        if !workspace.projects.contains(&path) {
+            workspace.projects.push(path);
+            save_workspace(host, window, &workspace.name, workspace.projects)?;
+        }
+        return Ok(project.root.clone().into());
+    }
+    if path == project.root {
+        return Ok(project.root.clone().into());
+    }
+    Ok(ide_workspace::workspace::Workspace::create_for_project(
+        &host.data_dir,
+        &project.root,
+        &info(&project).name,
+        &path,
+    )?
+    .into())
+}
+
 /// What [`set_settings`] changed; the caller tells the windows.
 pub struct SettingsApplied {
    pub settings: Settings,
@@ -107,6 +148,14 @@ pub fn set_settings(
        }
    }
    let affected = || if project_scope { current.iter().cloned().collect() } else { host.projects() };
+    if key == "editor" || key == "editor.encodings" || key == "editor.encodings.nativeToAscii" {
+        let affected = affected();
+        host.runtime.spawn_blocking(move || {
+            for project in affected {
+                project.documents.reload_properties();
+            }
+        });
+    }
    // File type associations re-detect open documents (off the command thread).
    if key == "files" || key.starts_with("files.fileType") {
        let affected = affected();
@@ -123,13 +172,23 @@ pub fn set_settings(
        host.apply_proxy();
    }
    // A new interpreter / toolchain / server executable restarts the language servers it affects.
-    if ["languages", "tools", "languageServers"].iter().any(|k| key == *k || key.starts_with(&format!("{k}."))) {
+    let code_style = key == "editor" || key == "editor.codeStyle" || key.starts_with("editor.codeStyle.");
+    let toolchain = ["languages", "tools", "languageServers", "projectStructure"]
+        .iter()
+        .any(|k| key == *k || key.starts_with(&format!("{k}.")));
+    // Code style only reaches servers as settings (e.g. jdtls' formatter profile); builds don't depend on it.
+    if code_style || toolchain {
        for project in affected() {
+            if toolchain && let Some(bridge) = &project.kotlin_bridge {
+                bridge.schedule();
+            }
            let lsp = project.lsp.clone();
            host.runtime.spawn(async move { lsp.reconfigure().await });
        }
    }
-    let roots_changed = key == "projectStructure" || key.starts_with("projectStructure.");
+    let roots_changed = key == "projectStructure"
+        || key.starts_with("projectStructure.")
+        || "languages.java.maven.unlinkedProjects".starts_with(key);
    // Content roots and excludes (files.exclude, ignored names, excluded folders) reach the
    // index and the watchers without reopening the project (the rescan runs in the background).
    if roots_changed || key == "files" || key.starts_with("files.") {
@@ -6,27 +6,80 @@ use std::time::Duration;

 /// Detected configs followed by user-defined ones (user ids win on conflict).
 pub fn configs(host: &Host, window: &str) -> IdeResult<Vec<RunConfig>> {
+    host.require_trust(window)?;
    let project = host.project(window)?;
    let root = project.root.clone();
    let user = ide_run::load_user_configs(&root)?;
-    let mut all: Vec<RunConfig> =
-        ide_run::detect(&root).into_iter().filter(|d| !user.iter().any(|u| u.id == d.id)).collect();
-    all.extend(user);
-    // Project interpreter / package manager / toolchains from Languages & Frameworks.
-    ide_sdk::apply::apply_to_run_configs(&mut all, &root, &project.settings.effective());
+    let root_suppressed = ide_run::load_suppressed_config_ids(&root)?;
+    let settings = project.settings.effective();
+    let mut all = detected_and_saved(&root, &settings, &user, &root_suppressed);
+    if let Some(workspace) = ide_workspace::workspace::Workspace::load(&root)? {
+        for member in workspace.projects.into_iter().filter(|p| p.is_dir()) {
+            let settings = ide_workspace::SettingsStore::load(&host.config_dir, Some(&member)).effective();
+            let saved = ide_run::load_user_configs(&member)?;
+            let suppressed = ide_run::load_suppressed_config_ids(&member)?;
+            let configs = detected_and_saved(&member, &settings, &saved, &suppressed);
+            let key = crate::project::project_key(&member);
+            let name = member.file_name().unwrap_or_default().to_string_lossy();
+            for mut config in configs {
+                for task in &mut config.extras.before_launch {
+                    if task.kind == "run" {
+                        task.target = format!("workspace:{}:{}", key, task.target);
+                    }
+                }
+                config.id = format!("workspace:{}:{}", key, config.id);
+                config.name = format!("{name} / {}", config.name);
+                config.cwd = Some(config.cwd.map(|p| member.join(&*p)).unwrap_or_else(|| member.clone()).into());
+                config.detected = true;
+                if !user.iter().any(|u| u.id == config.id) && !root_suppressed.contains(&config.id) {
+                    all.push(config);
+                }
+            }
+        }
+    }
    Ok(all)
 }

-pub fn save_configs(host: &Host, window: &str, configs: &[RunConfig]) -> IdeResult<()> {
-    ide_run::save_user_configs(&host.project(window)?.root, configs)
+/// A project's detected configurations (minus removed ones and unlinked Maven projects), then
+/// its saved ones; toolchains from Languages & Frameworks applied. Gradle choices stay as saved:
+/// derived defaults must not be written back as explicit environment.
+fn detected_and_saved(
+    root: &std::path::Path,
+    settings: &ide_core::settings::Settings,
+    saved: &[RunConfig],
+    suppressed: &[String],
+) -> Vec<RunConfig> {
+    let excluded_poms = crate::project::unlinked_maven_poms(root, settings);
+    let mut all: Vec<RunConfig> = ide_run::detect_excluding(root, &excluded_poms)
+        .into_iter()
+        .filter(|d| !suppressed.contains(&d.id) && !saved.iter().any(|u| u.id == d.id))
+        .collect();
+    all.extend(saved.iter().cloned());
+    for config in all.iter_mut().filter(|c| c.kind != "gradle") {
+        ide_sdk::apply::apply_to_run_configs(std::slice::from_mut(config), root, settings);
+    }
+    all
+}
+
+pub fn save_configs(
+    host: &Host,
+    window: &str,
+    configs: &[RunConfig],
+    removed_detected_ids: &[String],
+) -> IdeResult<()> {
+    ide_run::save_user_configs_with_removals(&host.project(window)?.root, configs, removed_detected_ids)
 }

 pub async fn start(host: &Host, window: &str, config: RunConfig, on_output: Emit<OutputChunk>) -> IdeResult<RunInfo> {
+    host.require_trust(window)?;
    let project = host.project(window)?;
    if config.command.is_empty() {
        return Err(IdeError::invalid("run configuration has no command"));
    }
    // Settings › Run Targets: over SSH.
+    if config.kind == "tomcat" && config.extras.target.as_deref().is_some_and(|t| !t.is_empty()) {
+        return Err(IdeError::invalid("Tomcat Local requires the local machine"));
+    }
    if config.extras.target.as_deref().is_some_and(|t| !t.is_empty()) {
        let settings = project.settings.effective();
        let out = on_output.clone();
@@ -35,19 +88,68 @@ pub async fn start(host: &Host, window: &str, config: RunConfig, on_output: Emit
            .run(&settings, &project.root, &config, project.sink.clone(), Box::new(move |c| out(c)))
            .await;
    }
-    let settings = project.settings.effective();
+    let member = ide_workspace::workspace::Workspace::load(&project.root)?.and_then(|workspace| {
+        let cwd = config.cwd.as_deref()?;
+        workspace.projects.into_iter().filter(|root| cwd.starts_with(root)).max_by_key(|root| root.components().count())
+    });
+    let root = member.as_ref().unwrap_or(&project.root);
+    let settings = match &member {
+        Some(root) => ide_workspace::SettingsStore::load(&host.config_dir, Some(root)).effective(),
+        None => project.settings.effective(),
+    };
    // Configurations made in the UI name bare tools (`godot`) that may live outside PATH.
    let mut config = config;
-    ide_sdk::apply::resolve_run_command(&mut config, &project.root, &settings);
+    if matches!(config.kind.as_str(), "gradle" | "tomcat") {
+        ide_sdk::apply::apply_to_run_configs(std::slice::from_mut(&mut config), root, &settings);
+    } else {
+        ide_sdk::apply::resolve_run_command(&mut config, root, &settings);
+    }
+    if config.kind == "go" {
+        ide_sdk::apply::apply_to_run_configs(std::slice::from_mut(&mut config), root, &settings);
+        ide_sdk::go::apply_to_run(&mut config, &settings.languages.go.build_tags);
+    }
    if config.command == ide_sdk::godot::COMMAND {
        return Err(IdeError::unavailable(ide_sdk::godot::NOT_FOUND));
    }
+    if config.kind == "tomcat" {
+        if host.processes.list().iter().any(|r| r.running && r.config_id == config.id) {
+            return Err(IdeError::invalid("This Tomcat configuration is already running"));
+        }
+        let (root, cache) = (root.clone(), project.cache_dir.clone());
+        config = tokio::task::spawn_blocking(move || {
+            ide_run::tomcat::prepare(&root, &cache, &mut config)?;
+            Ok::<_, IdeError>(config)
+        })
+        .await
+        .map_err(|e| IdeError::internal(e.to_string()))??;
+    }
+    if config.kind == "go" && config.extras.params.get("scope").is_some_and(|s| s == "file") {
+        let root = project.root.clone();
+        config = host
+            .blocking(move || {
+                ide_run::go::prepare_test_file(&root, &mut config)?;
+                Ok(config)
+            })
+            .await?;
+    }
    let encoding = settings.console.encoding;
    let options = StartOptions {
        encoding: Some(encoding).filter(|e| !e.trim().is_empty()),
-        python_paths: super::python::paths(&project),
+        python_paths: if member.is_some() { vec![root.clone()] } else { super::python::paths(&project) },
    };
-    host.processes.start(&project.root, &config, &options, project.sink.clone(), Box::new(move |c| on_output(c)))
+    project.require_trust()?;
+    let mut sink = project.sink.clone();
+    if config.kind == "go" && matches!(config.args.first().map(String::as_str), Some("mod" | "work")) {
+        let previous = sink;
+        let root = project.root.clone();
+        sink = std::sync::Arc::new(move |event: ide_core::IdeEvent| {
+            if matches!(&event, ide_core::IdeEvent::RunExited { .. }) {
+                ide_sdk::libraries::invalidate_go(&root);
+            }
+            previous.emit(event);
+        });
+    }
+    host.processes.start(&project.root, &config, &options, sink, Box::new(move |c| on_output(c)))
 }

 /// Stops a run (interrupt, then kill after Settings › Run's termination timeout).
@@ -5,6 +5,78 @@ use crate::rpc::Dispatcher;
 use ide_core::{IdeError, IdeResult};
 use ide_run::RunConfig;

+fn application_cache(project: &crate::project::Project, id: &str) -> std::path::PathBuf {
+    use std::hash::{Hash, Hasher};
+    let mut hash = std::collections::hash_map::DefaultHasher::new();
+    id.hash(&mut hash);
+    project.cache_dir.join("application-update").join(format!("{:x}", hash.finish()))
+}
+
+pub async fn run_application_build(
+    host: &Host,
+    window: &str,
+    config: RunConfig,
+    module: std::path::PathBuf,
+) -> IdeResult<RunConfig> {
+    host.require_trust(window)?;
+    if config.kind != "spring-boot" || config.extras.target.as_ref().is_some_and(|t| !t.is_empty()) {
+        return Err(IdeError::invalid("Application resource updates require a local Spring Boot configuration"));
+    }
+    let project = host.project(window)?;
+    tokio::task::spawn_blocking(move || {
+        let model = crate::ops::build::load(&project.root, &project.build_cache_dir(), &project.settings.effective());
+        let plan = ide_build::application_update::plan(
+            &project.root,
+            &model,
+            &module,
+            &application_cache(&project, &config.id),
+        )?;
+        let mut env = plan.env;
+        env.extend(config.env);
+        Ok(RunConfig {
+            id: format!("application-build:{}", config.id),
+            name: format!("Update {}", config.name),
+            kind: plan.kind.into(),
+            command: plan.command,
+            args: plan.args,
+            cwd: Some(project.root.join(plan.cwd).into()),
+            env,
+            detected: false,
+            is_test: false,
+            debug_adapter: None,
+            allow_parallel: false,
+            extras: ide_run::RunExtras {
+                include_system_env: config.extras.include_system_env,
+                env_files: config.extras.env_files,
+                ..Default::default()
+            },
+        })
+    })
+    .await
+    .map_err(|e| IdeError::internal(e.to_string()))?
+}
+
+pub async fn run_application_publish(
+    host: &Host,
+    window: &str,
+    config: RunConfig,
+    class_paths: Vec<String>,
+    main_class: String,
+) -> IdeResult<()> {
+    host.require_trust(window)?;
+    let project = host.project(window)?;
+    tokio::task::spawn_blocking(move || {
+        ide_build::application_update::publish(
+            &project.root,
+            &application_cache(&project, &config.id),
+            &class_paths,
+            &main_class,
+        )
+    })
+    .await
+    .map_err(|e| IdeError::internal(e.to_string()))?
+}
+
 /// Configuration templates: per-type defaults applied to new configurations.
 pub fn run_templates(host: &Host, window: &str) -> IdeResult<Vec<RunConfig>> {
    let root = host.project(window)?.root.clone();
@@ -49,8 +121,103 @@ pub async fn run_test_reports(
        .map_err(|e| IdeError::internal(e.to_string()))
 }

+pub async fn run_tomcat_home(host: &Host, window: &str, home: String) -> IdeResult<ide_run::tomcat::TomcatHome> {
+    host.require_trust(window)?;
+    let root = host.project(window)?.root.clone();
+    tokio::task::spawn_blocking(move || ide_run::tomcat::validate_home(&root.join(home)))
+        .await
+        .map_err(|e| IdeError::internal(e.to_string()))?
+}
+
+pub async fn run_tomcat_artifacts(host: &Host, window: &str) -> IdeResult<Vec<ide_build::web::WebArtifact>> {
+    host.require_trust(window)?;
+    let project = host.project(window)?;
+    tokio::task::spawn_blocking(move || {
+        let model = crate::ops::build::load(&project.root, &project.build_cache_dir(), &project.settings.effective());
+        ide_build::web::artifacts(&project.root, &model)
+    })
+    .await
+    .map_err(|e| IdeError::internal(e.to_string()))
+}
+
+pub async fn run_tomcat_build(host: &Host, window: &str, config: RunConfig) -> IdeResult<Option<RunConfig>> {
+    host.require_trust(window)?;
+    if config.extras.params.get("deployment").is_some_and(|v| v != "artifact") {
+        return Ok(None);
+    }
+    let project = host.project(window)?;
+    tokio::task::spawn_blocking(move || {
+        let model = crate::ops::build::load(&project.root, &project.build_cache_dir(), &project.settings.effective());
+        let artifacts = ide_build::web::artifacts(&project.root, &model);
+        let id = config
+            .extras
+            .params
+            .get("artifact")
+            .filter(|s| !s.is_empty())
+            .or_else(|| artifacts.first().map(|a| &a.id))
+            .ok_or_else(|| IdeError::invalid("Choose a WAR artifact"))?;
+        let mut plan = ide_build::web::build(
+            &project.root,
+            &model,
+            id,
+            &ide_run::tomcat::base_dir(&project.cache_dir, &config.id),
+        )?;
+        plan.env.extend(config.env.clone());
+        let mut build = RunConfig {
+            id: format!("tomcat-build:{}", config.id),
+            name: format!("Build {}", config.name),
+            kind: if id.starts_with("maven:") { "maven" } else { "gradle" }.into(),
+            command: plan.command.clone(),
+            args: vec![],
+            cwd: Some(std::path::PathBuf::from(&plan.cwd).into()),
+            env: plan.env.clone(),
+            detected: false,
+            is_test: false,
+            debug_adapter: None,
+            allow_parallel: false,
+            extras: ide_run::RunExtras {
+                include_system_env: config.extras.include_system_env,
+                env_files: config.extras.env_files,
+                ..Default::default()
+            },
+        };
+        plan.resolve_project(
+            &project.root,
+            &ide_run::resolved_env(&project.root, &build)?,
+            &ide_core::CancellationToken::new(),
+        )?;
+        build.args = plan.args;
+        Ok(Some(build))
+    })
+    .await
+    .map_err(|e| IdeError::internal(e.to_string()))?
+}
+
+pub async fn run_tomcat_update(host: &Host, window: &str, config: RunConfig, mode: String) -> IdeResult<()> {
+    host.require_trust(window)?;
+    let project = host.project(window)?;
+    if !host.processes.list().iter().any(|r| r.running && r.config_id == config.id) {
+        return Err(IdeError::invalid("Start this Tomcat configuration before updating it"));
+    }
+    tokio::task::spawn_blocking(move || ide_run::tomcat::update(&project.root, &project.cache_dir, &config, &mode))
+        .await
+        .map_err(|e| IdeError::internal(e.to_string()))?
+}
+
 /// Commands of this module the remote server answers.
 pub(crate) fn register(d: &mut Dispatcher) {
+    d.add("run_application_build", |c| async move {
+        run_application_build(&c.host, &c.window, c.arg("config")?, c.arg("module")?).await
+    });
+    d.add("run_application_publish", |c| async move {
+        run_application_publish(&c.host, &c.window, c.arg("config")?, c.arg("classPaths")?, c.arg("mainClass")?).await
+    });
+    d.add("run_tomcat_home", |c| async move { run_tomcat_home(&c.host, &c.window, c.arg("home")?).await });
+    d.add("run_tomcat_artifacts", |c| async move { run_tomcat_artifacts(&c.host, &c.window).await });
+    d.add("run_tomcat_build", |c| async move { run_tomcat_build(&c.host, &c.window, c.arg("config")?).await });
+    d.add("run_tomcat_update", |c| async move {
+        run_tomcat_update(&c.host, &c.window, c.arg("config")?, c.arg("mode")?).await
+    });
    d.add("run_templates", |c| async move { run_templates(&c.host, &c.window) });
    d.add("run_save_templates", |c| async move { run_save_templates(&c.host, &c.window, c.arg("templates")?) });
    d.add("run_system_env", |c| async move { Ok(run_system_env(&c.host, &c.window)) });
@@ -22,12 +22,14 @@ pub struct LocatedTools {

 /// Installed interpreters / toolchains of `kind`; project-local ones first.
 pub async fn sdk_detect(host: &Host, window: &str, kind: SdkKind) -> IdeResult<Vec<Sdk>> {
+    host.require_trust(window)?;
    let root = host.project(window).ok().map(|p| p.root.clone());
    tokio::task::spawn_blocking(move || ide_sdk::detect(kind, root.as_deref())).await.map_err(join_err)
 }

 /// The interpreter the project uses: the configured one, else its virtualenv.
 pub fn sdk_python_effective(host: &Host, window: &str) -> IdeResult<Option<ide_core::IpcPath>> {
+    host.require_trust(window)?;
    let project = host.project(window)?;
    Ok(ide_sdk::apply::python_interpreter(&project.root, &project.settings.effective()).map(Into::into))
 }
@@ -35,6 +37,7 @@ pub fn sdk_python_effective(host: &Host, window: &str) -> IdeResult<Option<ide_c
 /// SDK / library source folders shown under "External Libraries" in the Project view,
 /// with the Maven / Gradle dependency jars of the build model.
 pub async fn sdk_project_libraries(host: &Host, window: &str) -> IdeResult<Vec<ide_sdk::libraries::LibraryGroup>> {
+    host.require_trust(window)?;
    let project = host.project(window)?;
    let (root, cache, settings) = (project.root.clone(), project.build_cache_dir(), project.settings.effective());
    tokio::task::spawn_blocking(move || {
@@ -56,11 +59,12 @@ pub async fn sdk_project_libraries(host: &Host, window: &str) -> IdeResult<Vec<i

 /// Looks up `names` (bare command names): `node_modules/.bin` above `near`, then the search path.
 pub async fn sdk_locate_tools(
-    _host: &Host,
-    _window: &str,
+    host: &Host,
+    window: &str,
    names: Vec<String>,
    near: Option<PathBuf>,
 ) -> IdeResult<LocatedTools> {
+    host.require_trust(window)?;
    tokio::task::spawn_blocking(move || LocatedTools {
        tools: ide_sdk::locate::locate_tools(&names, near.as_deref()),
        compile_dir: ide_sdk::locate::compile_dir().into(),
@@ -72,13 +76,14 @@ pub async fn sdk_locate_tools(
 /// `base -m venv location`; output lines stream through `on_output`.
 pub async fn sdk_python_create_venv(
    host: &Host,
-    _window: &str,
+    window: &str,
    base: PathBuf,
    location: PathBuf,
    request: RequestId,
    on_output: Channel<String>,
 ) -> IdeResult<Sdk> {
-    let cancel = host.begin_request(request);
+    host.require_trust(window)?;
+    let cancel = host.begin_project_request(window, request);
    let result = tokio::task::spawn_blocking(move || {
        ide_sdk::python::create_venv(&base, &location, &cancel, &|line| {
            let _ = on_output.send(line);
@@ -92,11 +97,12 @@ pub async fn sdk_python_create_venv(

 pub async fn sdk_python_packages(
    host: &Host,
-    _window: &str,
+    window: &str,
    python: PathBuf,
    request: RequestId,
 ) -> IdeResult<Vec<PythonPackage>> {
-    let cancel = host.begin_request(request);
+    host.require_trust(window)?;
+    let cancel = host.begin_project_request(window, request);
    let result =
        tokio::task::spawn_blocking(move || ide_sdk::python::list_packages(&python, &cancel)).await.map_err(join_err);
    host.end_request(request);
@@ -107,7 +113,7 @@ pub async fn sdk_python_packages(
 #[allow(clippy::too_many_arguments)]
 pub async fn sdk_python_pip(
    host: &Host,
-    _window: &str,
+    window: &str,
    python: PathBuf,
    requirement: String,
    uninstall: bool,
@@ -115,7 +121,8 @@ pub async fn sdk_python_pip(
    request: RequestId,
    on_output: Channel<String>,
 ) -> IdeResult<()> {
-    let cancel = host.begin_request(request);
+    host.require_trust(window)?;
+    let cancel = host.begin_project_request(window, request);
    let result = tokio::task::spawn_blocking(move || {
        let send = |line: String| {
            let _ = on_output.send(line);
@@ -42,13 +42,16 @@ pub async fn start(
    let cancel = host.begin_request(request);
    let documents = project.documents.clone();
    let root = project.root.clone();
+    let workspace = ide_workspace::workspace::Workspace::load(&root)?.is_some();
    // The whole project also covers the Project Structure content roots.
    let content_roots = match query.scope {
-        ide_search::SearchScope::Project | ide_search::SearchScope::FileSet { set: ProjectFileSet::All } => {
-            project.content_roots()
-        }
+        ide_search::SearchScope::Project
+        | ide_search::SearchScope::FileSet { .. }
+        | ide_search::SearchScope::Pattern { .. } => project.content_roots(),
        _ => Vec::new(),
    };
+    let include_root = !workspace
+        || matches!(query.scope, ide_search::SearchScope::Directory { .. } | ide_search::SearchScope::Files { .. });
    let languages = project.languages.clone();
    let syntax = host.syntax();
    let events = on_event.clone();
@@ -66,15 +69,21 @@ pub async fn start(
                Some(found.into_iter().map(literal_range).collect())
            };
            let mut total = SearchSummary::default();
-            for dir in std::iter::once(&root).chain(&content_roots) {
+            for dir in std::iter::once(&root).filter(|_| include_root).chain(&content_roots) {
                let s = ide_search::search_in_context(
                    dir,
                    &query,
                    Some(&filter),
                    Some(&literals),
-                    &|p| documents.text_of(p),
+                    &|p| documents.search_text_of(p),
                    &cancel,
-                    &|file| events(SearchEvent::File { file }),
+                    &|mut file| {
+                        if dir != &root {
+                            let name = dir.file_name().unwrap_or_default().to_string_lossy();
+                            file.rel_path = format!("{name}/{}", file.rel_path);
+                        }
+                        events(SearchEvent::File { file });
+                    },
                )?;
                total.files += s.files;
                total.matches += s.matches;
@@ -124,7 +124,7 @@ pub async fn syntax_identifiers_in_files(
                let snap = project.documents.text_snapshot(doc).ok()?;
                return (!snap.large).then_some((snap.language, Some((doc, snap.version)), snap.text));
            }
-            let text = ide_vfs::load_text(path).ok()?.text;
+            let text = project.text_of(path).ok()?;
            let first_line = text.lines().next();
            Some((languages.detect(path, first_line), None, text))
        };
@@ -3,12 +3,28 @@ use crate::Host;
 use ide_core::{IdeResult, TerminalId};
 use ide_terminal::{TerminalInfo, TerminalOptions};

-pub fn spawn(host: &Host, window: &str, options: TerminalOptions, on_output: Emit<String>) -> IdeResult<TerminalInfo> {
-    // Python › "Activate virtualenv": typed into the new shell, like PyCharm.
+pub fn spawn(
+    host: &Host,
+    window: &str,
+    mut options: TerminalOptions,
+    on_output: Emit<String>,
+) -> IdeResult<TerminalInfo> {
+    if !host.project(window).is_ok_and(|p| p.is_trusted()) {
+        // Project terminal settings can otherwise start a command as soon as a tab restores.
+        let global = host.global_settings.effective().terminal;
+        options.shell = None;
+        options.args.clear();
+        options.env = global.env;
+    }
+    let (shell, args) = ide_terminal::resolve_shell(options.shell.as_deref(), &options.args);
+    options.shell = Some(shell.clone());
+    options.args = args;
+    // Python › "Activate virtualenv": typed into the same shell the PTY starts.
    let activation = host
        .project(window)
        .ok()
-        .and_then(|p| ide_sdk::apply::terminal_activation(&p.root, &p.settings.effective(), options.shell.as_deref()));
+        .filter(|p| p.is_trusted())
+        .and_then(|p| ide_sdk::apply::terminal_activation(&p.root, &p.settings.effective(), &shell));
    let info = host.terminals.spawn(options, host.window_sink(window), Box::new(move |chunk| on_output(chunk)))?;
    if let Some(line) = activation {
        let _ = host.terminals.write(info.id, &format!(" {line}\r"));