Update NPM readme (#3510)

closes #3497
closes #3502

.env.example

@@ -2,9 +2,9 @@
 # docker-compose.full.yml up -d`. None of the defaults below are safe for
 # anything beyond a local laptop test.
 
-# ── Public-facing ports (nginx) ---------------------------------------
+# ── Public-facing ports (Caddy) ---------------------------------------
 HTTP_PORT=80
-# HTTPS_PORT=443     # uncomment after you enable TLS in nginx/nginx.conf
+# HTTPS_PORT=443     # uncomment after you enable TLS in caddy/Caddyfile
 
 # ── MariaDB ------------------------------------------------------------
 MARIADB_ROOT_PASSWORD=replace-with-strong-password

.github/workflows/docker-image.yaml

@@ -87,6 +87,8 @@ jobs:
                   platforms: linux/amd64,linux/arm64
                   context: .
                   push: true
+                  provenance: mode=max
+                  sbom: true
                   tags: ${{ steps.meta.outputs.tags }}
                   labels: ${{ steps.meta.outputs.labels }}
                   cache-from: type=gha

AGENTS.md

@@ -10,6 +10,7 @@ Use these as the source of truth before exploring further:
 - [doc/architecture.md](doc/architecture.md) — backend layered stack (controllers → drivers → services → stores → clients), `PuterServer` wiring, `Context` (ALS), and extensions.
 - [doc/contributing-apis.md](doc/contributing-apis.md) — adding and maintaining public APIs end to end (backend surface → puter.js → types → docs → tests). Follow it for any API work.
 - [doc/pagination.md](doc/pagination.md) — the one pagination convention for list APIs (limit/cursor/offset/includeTotal, envelope shape, cursor semantics).
+- [doc/alarms.md](doc/alarms.md) — raising alarms and picking a severity (what pages, what only gets recorded), plus the config that routes them.
 - [doc/self-hosting.md](doc/self-hosting.md) — running Puter outside hosted infra.
 - [CONTRIBUTING.md](CONTRIBUTING.md) — testing, security, AI-assisted code, PR conventions, Boy Scout Rule.
 - [SECURITY.md](SECURITY.md) — how to report vulnerabilities (do not file them publicly).

caddy/Caddyfile

@@ -0,0 +1,73 @@
+# Reverse proxy in front of Puter — mirrors what the prod ALB does:
+# accepts every Host header, forwards to the Puter container, and lets
+# the Puter app handle subdomain-based routing internally (api.*,
+# site.*, app.*, dev.*, plus the per-user subdomains under those).
+#
+# To enable TLS:
+#   1. Drop a wildcard fullchain.pem + privkey.pem into ./puter/tls/
+#      (see "Step 3 — TLS" in doc/self-hosting.md).
+#   2. Uncomment the `:443` block at the bottom of this file, and swap the
+#      `:80` block for the redirect shown alongside it.
+#   3. Uncomment the `443:443` port mapping under the `caddy` service in
+#      docker-compose.yml, and HTTPS_PORT in .env.
+#   4. Set `"protocol": "https"` and `"pub_port": 443` in config.json.
+{
+	# Certs are supplied by the operator, not issued by Caddy. Puter serves
+	# per-user sites and apps on dynamic subdomains (<name>.site.<domain>,
+	# <name>.app.<domain>) — only a DNS-01 wildcard cert covers those, and
+	# DNS-01 needs a provider plugin that isn't in the stock caddy image.
+	# `off` stops Caddy attempting ACME on boot (it would fail and leave the
+	# site unreachable) and stops it inventing its own http→https redirects.
+	auto_https off
+}
+
+# Shared handling, imported by the HTTP and HTTPS site blocks below so the
+# two can't drift apart.
+(puter_routes) {
+	# Rough size cap that mirrors prod ALB defaults; tune for your uploads.
+	# Puter chunks large uploads, so 1 GiB per request is plenty.
+	request_body {
+		max_size 1024MiB
+	}
+
+	# RustFS — see the `s3` service in docker-compose.yml. Browsers PUT/GET
+	# here for presigned-URL uploads / downloads. Matched on the `s3.`
+	# subdomain of whatever the install domain is, so signature verification
+	# works (Caddy preserves the original Host end-to-end) and HTTPS stays
+	# clean — no mixed content from a port-9000 host publish.
+	@s3 header_regexp Host ^s3\.
+	handle @s3 {
+		reverse_proxy s3:9000
+	}
+
+	# Everything else, on every Host, goes to Puter — which routes on that
+	# Host internally. Caddy forwards it unchanged and adds X-Forwarded-For
+	# / -Proto / -Host, which is what `trust_proxy` in config.json counts.
+	handle {
+		reverse_proxy puter:4100 {
+			# Stream responses through unbuffered — Puter uses SSE and
+			# socket.io. WebSocket upgrades need no config of their own;
+			# Caddy proxies them by default.
+			flush_interval -1
+		}
+	}
+}
+
+# ── HTTP (port 80) ─────────────────────────────────────────────────────
+# A site address with no hostname is the catch-all: it answers for every
+# Host, which is what Puter's subdomain routing requires.
+:80 {
+	import puter_routes
+}
+
+# ── HTTPS (port 443) — uncomment after dropping certs in ./puter/tls/ ──
+# Replace the `:80` block above with a redirect to force HTTPS everywhere:
+#
+# :80 {
+# 	redir https://{host}{uri} permanent
+# }
+#
+# :443 {
+# 	tls /etc/caddy/tls/fullchain.pem /etc/caddy/tls/privkey.pem
+# 	import puter_routes
+# }

config.default.json

@@ -5,9 +5,7 @@
     "protocol": "http",
     "domain": "puter.localhost",
     "cookie_name": "puter_auth_token",
-    "jwt_secret": "dev-jwt-secret-change-me",
     "jwt_secret_v2": "dev-jwt-secret-v2-change-me",
-    "allow_v1_tokens": true,
     "url_signature_secret": "dev-url-signature-secret-change-me",
     "allow_all_host_values": true,
     "allow_no_host_header": true,

config.template.jsonc

@@ -73,11 +73,7 @@
 
     // ── Auth / session ──────────────────────────────────────────────────
     // ALWAYS replace these for any public install — `openssl rand -hex 64`.
-    // `jwt_secret` is legacy verify-only; new tokens sign with `jwt_secret_v2`.
-    "jwt_secret": "change-me",
     "jwt_secret_v2": "change-me",
-    // Set false to retire v1 tokens entirely (ROLLOUT-1).
-    "allow_v1_tokens": true,
     "url_signature_secret": "change-me",
     "cookie_name": "puter_auth_token",
     "min_pass_length": 6,
@@ -255,6 +251,60 @@
         }
     },
 
+    // ── Alarms / alerting ───────────────────────────────────────────────
+    // Where system alarms go. Severity is the routing decision — each
+    // transport takes everything at or above its own `minSeverity`:
+    //
+    //   critical — an unhandled server error; pages on-call.
+    //   error    — pages as well; prefer critical or warning.
+    //   warning  — look at it today; no page.
+    //   info     — a record in the chat channel only.
+    //
+    // Both transports are off unless enabled, so a self-hosted node just
+    // logs its alarms to the console.
+    "pager": {
+        // Severity for call sites that don't pick one. Default "critical".
+        "defaultSeverity": "critical",
+
+        // Retier or silence an alarm without a deploy. Keys are alarm ids,
+        // or a prefix ending in `*`; the exact id wins over a pattern, and
+        // the longest matching pattern wins among patterns. Values are a
+        // severity or "mute". This is applied last, so it overrides both the
+        // call site and any known-error rule.
+        "severityOverrides": {
+            // "cronMonitor:*": "info",
+            // "http_500:GET:/some/flapping/route:*": "mute"
+        },
+
+        "pagerduty": {
+            "enabled": false,
+            "routingKey": "",
+            // Lowest severity that reaches PagerDuty. Default "warning",
+            // which keeps `info` out of the paging system entirely.
+            "minSeverity": "warning"
+        },
+
+        // Slack incoming webhook — the low-noise destination for everything
+        // that shouldn't page.
+        "slack": {
+            "enabled": false,
+            "webhookUrl": "",
+            // Optional; defaults to the channel the webhook was created for.
+            "channel": "#alerts",
+            "username": "puter-alarms",
+            // Severity window posted to Slack. The ceiling defaults to
+            // "info" when PagerDuty is configured — what pages belongs in
+            // the pager, not in chat — and to "critical" when Slack is the
+            // only transport.
+            "minSeverity": "info",
+            "maxSeverity": "info",
+            // Don't repost the same alarm id within this window. The first
+            // occurrence always posts; the next post that gets through
+            // reports how many occurrences piled up. 0 disables throttling.
+            "repeatThrottleMs": 900000
+        }
+    },
+
     // ── Rate limiting ───────────────────────────────────────────────────
     // `memory` for single-node, `redis` for multi-node (default), `kv` for
     // dynamo-backed counters.
@@ -287,6 +337,10 @@
             "apiKey": "",
             "apiBaseUrl": "https://openrouter.ai/api/v1"
         },
+        "infron": {
+            "apiKey": "",
+            "apiBaseUrl": "https://llm.onerouter.pro/v1"
+        },
         "together-ai": { "apiKey": "" },
         // Local Ollama. `enabled: false` skips the auto-probe at startup
         // (otherwise Puter logs ECONNREFUSED on every boot when no Ollama
@@ -325,6 +379,7 @@
             "secret_key": "",
             "region": "us-west-2"
         },
+        "speechify": { "apiKey": "" },
         "aws-textract": {
             "access_key": "",
             "secret_key": "",

doc/alarms.md

@@ -0,0 +1,113 @@
+# Alarms
+
+`clients.alarm` is the one way code reports that something is wrong. It
+de-dupes by alarm id, counts occurrences, and routes each alarm to alert
+transports by **severity**.
+
+```ts
+this.clients.alarm.create(
+    `driver_rate_limit_hit:${iface}:${method}`, // de-dupe key
+    `Driver rate limit hit on ${iface}:${method}`, // what a human reads
+    { iface, method, userUuid }, // context fields
+    'info', // severity
+);
+```
+
+## Severity is the routing decision
+
+| Severity   | Meaning                                                | Goes to     |
+| ---------- | ------------------------------------------------------ | ----------- |
+| `critical` | An unhandled server error. Someone gets woken up.      | Pager       |
+| `error`    | Same urgency as critical; prefer one of the other two. | Pager       |
+| `warning`  | Worth a look today. Nobody is paged.                   | Pager (low) |
+| `info`     | A record of something expected-but-notable.            | Chat        |
+
+Each transport declares the severity window it accepts, so the value a call
+site passes is what decides where the alarm lands. The two windows don't
+overlap by default: anything that pages lives in the paging system, and chat
+is the record of what didn't. The bar for `critical` is
+deliberately high: an unhandled 5xx out of the HTTP error handler is the main
+thing that still pages. Anything a human can look at tomorrow is `warning`,
+and anything that's just worth recording is `info`.
+
+Omitting the severity takes `pager.defaultSeverity` (itself `critical`), so
+pass one explicitly unless you really mean "page someone".
+
+### Choosing one
+
+- Did the server fail to do its job in a way nobody expected? → `critical`
+- Is a background job, rate, or dependency degraded? → `warning`
+- Is this a user doing something notable (hitting a limit, tripping an abuse
+  heuristic, overspending)? → `info`
+
+An extension whose signals are all one tier can default its own local
+`raiseAlarm` helper to that tier instead of repeating it at every call site —
+see [extensions/cronMonitor](../../../extensions/cronMonitor/index.js).
+
+## One incident per occurrence, unless you say otherwise
+
+Alarms always de-dupe *in process* — repeats of an id bump its occurrence
+count rather than creating a second alarm. What that means for the pager is a
+separate decision, and by default every occurrence opens its own PagerDuty
+incident: two failed scans an hour apart are two things that happened, and
+closing one shouldn't hide the other.
+
+Pass `{ dedup: true }` as a fifth argument when repeats of the id really are
+one recurring fault, and they collapse onto a single incident carrying the
+occurrence count:
+
+```ts
+this.clients.alarm.create(alarmId, message, fields, 'critical', {
+    dedup: true,
+});
+```
+
+The HTTP error handler uses it: its id is route + error signature, so a hot
+loop of the same crash is one incident with N occurrences instead of N pages.
+Reach for it anywhere else only when the id is that specific — otherwise a
+per-request alarm can flood the pager.
+
+## Configuration
+
+Everything lives under `pager` in config (see
+[config.template.jsonc](../config.template.jsonc) for the annotated version).
+Both transports are off unless enabled, so a self-hosted node just logs
+alarms to the console.
+
+```jsonc
+"pager": {
+    "defaultSeverity": "critical",
+    "severityOverrides": { "cronMonitor:*": "info" },
+    "pagerduty": { "enabled": true, "routingKey": "…", "minSeverity": "warning" },
+    "slack": {
+        "enabled": true,
+        "webhookUrl": "…",
+        "channel": "#alerts",
+        "minSeverity": "info",
+        "maxSeverity": "info",
+        "repeatThrottleMs": 900000,
+    },
+}
+```
+
+Slack's `maxSeverity` defaults to `info` whenever PagerDuty is configured, and
+to `critical` when it isn't — a node with only a webhook still sees
+everything. Raise it to have chat mirror the paging tiers as well.
+
+### Retiering without a deploy
+
+`severityOverrides` is the escape hatch for an alarm that turns out to be
+noisier or more serious than its call site assumed. Keys are alarm ids or a
+prefix ending in `*`; the exact id beats a pattern, and the longest matching
+prefix wins among patterns. Values are a severity, or `mute` to drop the
+alarm before any transport sees it.
+
+It is applied *after* the call site's severity and any known-error rule, so
+config always has the last word.
+
+### Repeat throttling
+
+The chat transport won't repost the same alarm id within
+`repeatThrottleMs` (default 15 minutes). The first occurrence always posts,
+and the next one that gets through reports how many piled up in between —
+so a hot loop reads as one message with a count, not a wall of them.

doc/self-hosting.md

@@ -1,6 +1,6 @@
 # Self-Hosting Puter
 
-`docker-compose.yml` brings up Puter **plus every external service it needs** — MariaDB, Valkey, DynamoDB-local, RustFS S3, nginx — wired together. Closest thing to a production deployment you can self-manage on a single host.
+`docker-compose.yml` brings up Puter **plus every external service it needs** — MariaDB, Valkey, DynamoDB-local, RustFS S3, Caddy — wired together. Closest thing to a production deployment you can self-manage on a single host.
 
 ## One-line installer (recommended)
 
@@ -8,7 +8,7 @@
 curl -fsSL https://raw.githubusercontent.com/HeyPuter/puter/main/install.sh | sh
 ```
 
-Generates secrets, writes `.env` + `puter/config/config.json`, downloads `docker-compose.yml` from the OSS repo, and runs `docker compose up -d`. Re-running is safe — it won't overwrite existing config (set `PUTER_FORCE=1` to rotate). Use the manual steps below if you want to inspect or tweak each step yourself.
+Generates secrets, writes `.env` + `puter/config/config.json`, downloads `docker-compose.yml` + `caddy/Caddyfile` from the OSS repo, and runs `docker compose up -d`. Re-running is safe — it won't overwrite existing config (set `PUTER_FORCE=1` to rotate). Use the manual steps below if you want to inspect or tweak each step yourself.
 
 ## Requirements
 
@@ -20,7 +20,7 @@ Generates secrets, writes `.env` + `puter/config/config.json`, downloads `docker
 
 | Container       | Image                    | Role                                                       |
 | --------------- | ------------------------ | ---------------------------------------------------------- |
-| `puter-nginx`   | `nginx:1.27-alpine`      | Reverse proxy on 80 (and 443 if TLS); forwards to Puter    |
+| `puter-caddy`   | `caddy:2.11-alpine`      | Reverse proxy on 80 (and 443 if TLS); forwards to Puter    |
 | `puter`         | `ghcr.io/heyputer/puter` | The app                                                    |
 | `puter-mariadb` | `mariadb:11`             | SQL database — schema applied automatically on first boot  |
 | `puter-valkey`  | `valkey/valkey:8-alpine` | Redis-compatible cache + rate-limiter                      |
@@ -47,7 +47,6 @@ State lives under `./puter/data/<service>/`.
 MARIADB_ROOT_PASSWORD=$(openssl rand -hex 32)
 MARIADB_PASSWORD=$(openssl rand -hex 32)
 S3_SECRET_KEY=$(openssl rand -hex 32)
-JWT_SECRET=$(openssl rand -hex 64)
 JWT_SECRET_V2=$(openssl rand -hex 64)
 URL_SIGNATURE_SECRET=$(openssl rand -hex 64)
 
@@ -65,7 +64,7 @@ S3_SECRET_KEY=$S3_SECRET_KEY
 S3_BUCKET=puter-local
 EOF
 
-mkdir -p puter/config puter/data puter/tls
+mkdir -p puter/config puter/data puter/data/caddy puter/tls
 cat > puter/config/config.json <<EOF
 {
     "domain": "puter.localhost",
@@ -78,9 +77,7 @@ cat > puter/config/config.json <<EOF
     "private_app_hosting_domain": "app.puter.localhost",
     "private_app_hosting_domain_alt": "dev.puter.localhost",
 
-    "jwt_secret": "$JWT_SECRET",
     "jwt_secret_v2": "$JWT_SECRET_V2",
-    "allow_v1_tokens": true,
     "url_signature_secret": "$URL_SIGNATURE_SECRET",
 
     "database": {
@@ -134,21 +131,21 @@ Replace `puter.localhost`, `site.puter.localhost`, `host.puter.localhost`, `dev.
 
 Why these knobs:
 
-- `jwt_secret` + `jwt_secret_v2` — Puter signs new auth tokens with `jwt_secret_v2` (v2 token format, `kid: 'v2'` JWT header). `jwt_secret` is verify-only and lets tokens minted before this version (cookies still in users' browsers, stored API tokens) keep working. `allow_v1_tokens: true` keeps that fallback enabled. Fresh installs can leave it as-is; future versions will flip the flag to `false` and retire `jwt_secret` entirely once legacy tokens have drained.
+- `jwt_secret_v2` — the HMAC secret Puter signs and verifies auth tokens with (`kid: 'v2'` JWT header). The pre-v2 token format is retired: a token signed with the old `jwt_secret` no longer verifies, and holders are asked to sign in again. If you are upgrading from a release that had `jwt_secret`, drop it from your config — it is ignored.
 - `env: "prod"` — the bundled `config.default.json` ships with `env: "dev"` (matches the source-tree `npm run start:gui` workflow, which expects webpack-dev-server emitting a CSS manifest). Self-host runs against pre-built static bundles, so `env: "prod"` makes the homepage emit the `/dist/bundle.min.css` `<link>` tag instead of waiting on a manifest that doesn't exist.
 - `database.migrationPaths` — Puter applies the bundled MySQL/MariaDB schema on boot. The migration files are idempotent, so it is safe to leave this configured across restarts.
 - `dynamo.bootstrapTables: true` — Puter creates its KV table on boot. **Only set against a local emulator**, never real AWS.
 - `dynamo.aws` keys are dummies; DynamoDB-local doesn't validate them but the AWS SDK requires _something_. **Note:** DynamoDB uses `access_key` / `secret_key` (snake_case); S3 below uses `accessKeyId` / `secretAccessKey` (camelCase). Not interchangeable.
 - `providers.ollama.enabled: false` — Puter auto-probes a local Ollama at `127.0.0.1:11434` by default; without one running you'd see `ECONNREFUSED` on every boot. To run a bundled Ollama, see [Optional: local LLM (Ollama)](#optional-local-llm-ollama) below.
 - `s3.s3Config.forcePathStyle: true` — RustFS / MinIO / fauxqs need path-style URLs (`<endpoint>/<bucket>`). Real AWS S3 wants virtual-hosted (`<bucket>.<endpoint>`) — drop this flag (or set `false`) when you swap to real S3.
-- `s3.s3Config.publicEndpoint` — `endpoint` (`http://s3:9000`) only resolves inside the docker network; presigned upload/download URLs handed to the browser need a host-reachable URL. nginx routes the `s3.<domain>` subdomain to RustFS internally and preserves the Host header end-to-end (required for S3 signature validation), so the browser hits the same port/protocol as the rest of the app — no separate published port, no mixed-content surprises when you turn on TLS. Switch to `https://s3.<your-domain>` once you enable TLS in Step 3. Real AWS S3 doesn't need this — its endpoint is already public; drop the field entirely.
-- `trust_proxy: 1` — nginx terminates TLS and forwards `X-Forwarded-For`. Without this, `req.ip` is the docker-network address of the nginx container instead of the real client IP, which breaks rate limiting and IP-based audit logs. `1` = one trusted hop (nginx). Bump to `2` if you put Cloudflare in front of nginx; never set `true` (it trusts every hop and makes XFF forgeable).
+- `s3.s3Config.publicEndpoint` — `endpoint` (`http://s3:9000`) only resolves inside the docker network; presigned upload/download URLs handed to the browser need a host-reachable URL. Caddy routes the `s3.<domain>` subdomain to RustFS internally and preserves the Host header end-to-end (required for S3 signature validation), so the browser hits the same port/protocol as the rest of the app — no separate published port, no mixed-content surprises when you turn on TLS. Switch to `https://s3.<your-domain>` once you enable TLS in Step 3. Real AWS S3 doesn't need this — its endpoint is already public; drop the field entirely.
+- `trust_proxy: 1` — Caddy terminates TLS and forwards `X-Forwarded-For`. Without this, `req.ip` is the docker-network address of the Caddy container instead of the real client IP, which breaks rate limiting and IP-based audit logs. `1` = one trusted hop (Caddy). Bump to `2` if you put Cloudflare in front of Caddy; never set `true` (it trusts every hop and makes XFF forgeable).
 
 > If you ever change `MARIADB_PASSWORD` after first boot, `.env` alone won't update MariaDB — its credentials are baked into `./puter/data/mariadb/` on first init. Either rotate the password inside MariaDB by hand or `docker compose down && rm -rf ./puter/data/mariadb` to start fresh.
 
 ## Step 2 — Point DNS at the server \[Optional\]
 
-In your DNS provider, add records for the main domain plus the subdomains Puter and nginx route on (`api.*`, `site.*`, `app.*`, `s3.*`):
+In your DNS provider, add records for the main domain plus the subdomains Puter and Caddy route on (`api.*`, `site.*`, `app.*`, `s3.*`):
 
 ```
 A      puter.localhost          → <your server's public IP>
@@ -163,7 +160,7 @@ A      dev.puter.localhost      → <your server's public IP>
 A      *.dev.puter.localhost    → <your server's public IP>
 ```
 
-The wildcards are required — Puter routes via subdomains (`api.*`, `app.*`, etc.) and nginx routes browser S3 traffic via `s3.*` to RustFS.
+The wildcards are required — Puter routes via subdomains (`api.*`, `app.*`, etc.) and Caddy routes browser S3 traffic via `s3.*` to RustFS.
 
 ## Step 3 — TLS (recommended for public installs) \[Optional\]
 
@@ -182,13 +179,15 @@ sudo certbot certonly --manual --preferred-challenges dns \
 
 The cert needs to cover `*.puter.localhost` so that `s3.puter.localhost` (browser S3 endpoint), plus Puter's own `api.*` / `app.*` subdomains, all validate.
 
+> **Why not Caddy's automatic HTTPS?** Caddy issues certs over ACME by itself, but only for hostnames it knows up front, and only over HTTP-01 with the stock image. Puter serves every user's site and app on a subdomain it invents at runtime (`<name>.site.<domain>`, `<name>.app.<domain>`), which needs a **wildcard** cert — and wildcards require DNS-01, which requires a DNS-provider plugin that isn't in `caddy:2.11-alpine`. So `caddy/Caddyfile` sets `auto_https off` and reads the cert you supply below. If you'd rather have Caddy manage certs, build an image with the plugin for your DNS provider (`xcaddy build --with github.com/caddy-dns/<provider>`) and swap the `tls` line for a `tls { dns <provider> … }` block.
+
 Drop the resulting `fullchain.pem` and `privkey.pem` into `./puter/tls/`.
 
-**Wire nginx to use them:**
+**Wire Caddy to use them:**
 
-1. Open [nginx/nginx.conf](../nginx/nginx.conf), uncomment **both** `# server { listen 443 ssl … }` blocks (one for `s3.*`, one for the catch-all).
-2. (Optional) Replace the body of the port-80 blocks with `return 301 https://$host$request_uri;` to force HTTPS everywhere.
-3. In [docker-compose.yml](../docker-compose.yml), uncomment the `443:443` port mapping under the `nginx` service.
+1. Open [caddy/Caddyfile](../caddy/Caddyfile) and uncomment the `# :443 { … }` block at the bottom.
+2. (Optional but recommended) Replace the plain `:80 { import puter_routes }` block with the `redir` version shown alongside it, to force HTTPS everywhere.
+3. In [docker-compose.yml](../docker-compose.yml), uncomment the `443:443` port mapping under the `caddy` service.
 4. In `.env`, uncomment `HTTPS_PORT=443`.
 5. In `config.json`, switch:
     ```json
@@ -201,9 +200,9 @@ Drop the resulting `fullchain.pem` and `privkey.pem` into `./puter/tls/`.
 
 ## Running behind your own reverse proxy
 
-The bundled `puter-nginx` mirrors production and is the supported default — it terminates TLS (Step 3) and forwards every Host to Puter. But plenty of self-hosters already run their own edge proxy (Caddy, Traefik, HAProxy, a cloud load balancer, another nginx). You can put Puter behind it instead; Puter doesn't terminate TLS itself in any setup, so "your proxy does TLS" is just a matter of pointing it at the Puter container and getting a handful of details right.
+The bundled `puter-caddy` mirrors production and is the supported default — it terminates TLS (Step 3) and forwards every Host to Puter. But plenty of self-hosters already run their own edge proxy (Traefik, nginx, HAProxy, a cloud load balancer, another Caddy). You can put Puter behind it instead; Puter doesn't terminate TLS itself in any setup, so "your proxy does TLS" is just a matter of pointing it at the Puter container and getting a handful of details right.
 
-You can keep the bundled nginx as the single hop your proxy talks to, or bypass it and forward straight to the Puter container on port `4100` (uncomment the `4100:4100` mapping under the `puter` service in [docker-compose.yml](../docker-compose.yml), or attach your proxy to the compose network). Either works — what matters is the rules below.
+You can keep the bundled Caddy as the single hop your proxy talks to, or bypass it and forward straight to the Puter container on port `4100` (uncomment the `4100:4100` mapping under the `puter` service in [docker-compose.yml](../docker-compose.yml), or attach your proxy to the compose network). Either works — what matters is the rules below.
 
 **The rules that actually matter** (getting any of these wrong is what causes the redirect loops and "Invalid Host header" failures people hit):
 
@@ -219,7 +218,7 @@ You can keep the bundled nginx as the single hop your proxy talks to, or bypass
     - `X-Forwarded-For` — the real client IP (rate limiting + audit logs).
     - `Upgrade` / `Connection` — passed through for WebSocket / socket.io upgrades, or the realtime connection silently fails.
 
-5. **Set `trust_proxy` to the number of hops in front of Puter.** One external proxy talking directly to Puter → `"trust_proxy": 1` (installer: `PUTER_TRUST_PROXY=1`). A second proxy in front (e.g. Cloudflare → your proxy → Puter) → `2`. This is the count of proxies between the client and Puter, **including** the bundled nginx if you keep it. Too low and `req.ip` becomes a proxy address (breaks rate limiting); never set `true` (it trusts every hop and makes `X-Forwarded-For` forgeable).
+5. **Set `trust_proxy` to the number of hops in front of Puter.** One external proxy talking directly to Puter → `"trust_proxy": 1` (installer: `PUTER_TRUST_PROXY=1`). A second proxy in front (e.g. Cloudflare → your proxy → Puter) → `2`. This is the count of proxies between the client and Puter, **including** the bundled Caddy if you keep it. Too low and `req.ip` becomes a proxy address (breaks rate limiting); never set `true` (it trusts every hop and makes `X-Forwarded-For` forgeable).
 
 6. **Route the wildcard to Puter.** Your proxy must forward `*.<domain>` (covering `api.*`, `app.*`, and `s3.<domain>`) and `*.site.<domain>` (and any other hosting domains) to Puter — same wildcard DNS as Step 2. Puter does the per-subdomain routing internally; the proxy just needs to hand it the traffic with the Host intact.
 
@@ -227,6 +226,8 @@ With those in place the rest of the stack is unchanged — `docker compose up -d
 
 ## Step 4 — Bring it up
 
+Both [docker-compose.yml](../docker-compose.yml) and [caddy/Caddyfile](../caddy/Caddyfile) need to sit next to your `.env` — clone the repo, or copy those two paths out of it. The Caddyfile is bind-mounted read-only; if it's missing, Docker creates a *directory* at that path and `puter-caddy` dies with "not a directory".
+
 ```bash
 docker compose up -d
 ```
@@ -469,7 +470,7 @@ Migrations re-apply idempotently across pulls. Volumes are preserved.
 
 ## Troubleshooting
 
-**Site loads but I get "Bad Gateway" / nginx errors.**
+**Site loads but I get a 502 / "Bad Gateway" from Caddy.**
 The puter container failed to come up. `docker compose logs puter` will tell you which dependency rejected it (most often DB password mismatch between `.env` and `config.json`).
 
 **Login screen says "admin password not set".**

docker-compose.yml

@@ -2,7 +2,7 @@
 # Self-hosted Puter — full stack.
 #
 # Brings up Puter + every external service it needs:
-#   - nginx    : reverse proxy (mirrors prod ALB; handles TLS + Host fan-out)
+#   - caddy    : reverse proxy (mirrors prod ALB; handles TLS + Host fan-out)
 #   - valkey   : redis-compatible cache / rate-limiter backend
 #   - mariadb  : SQL database (Puter applies its schema on first boot)
 #   - dynamo   : DynamoDB-local (KV store; Puter creates the table itself)
@@ -23,7 +23,8 @@
 #
 # Production:
 #   - Always replace the default passwords / S3 keys / Puter secrets.
-#   - Front Puter with TLS-terminating reverse proxy (Caddy / nginx).
+#   - Enable TLS on the bundled Caddy (see caddy/Caddyfile) or front the
+#     stack with your own TLS-terminating proxy.
 #   - Move state-bearing volumes to a backed-up location.
 
 services:
@@ -118,7 +119,7 @@ services:
       RUSTFS_SECRET_KEY: ${S3_SECRET_KEY:-puter-secret-change-me}
     volumes:
       - ./puter/data/s3:/data:z
-    # Internal-only — browsers reach RustFS via nginx (`s3.<domain>`),
+    # Internal-only — browsers reach RustFS via Caddy (`s3.<domain>`),
     # which preserves the Host header for S3 signature validation and
     # rides the same TLS termination as Puter. Uncomment to also expose
     # 9000 directly on the host for `aws-cli` / debugging.
@@ -249,7 +250,7 @@ services:
         condition: service_started
       s3-init:
         condition: service_completed_successfully
-    # Internal-only: nginx reaches it on the compose network. Uncomment
+    # Internal-only: Caddy reaches it on the compose network. Uncomment
     # to also expose port 4100 directly on the host (useful for debugging).
     # ports:
     #   - "4100:4100"
@@ -270,23 +271,32 @@ services:
       retries: 3
       start_period: 30s
 
-  nginx:
-    image: nginx:1.27-alpine
-    container_name: puter-nginx
+  caddy:
+    image: caddy:2.11-alpine
+    container_name: puter-caddy
     restart: unless-stopped
     depends_on:
       puter:
         condition: service_started
     ports:
       - "${HTTP_PORT:-80}:80"
-      # Uncomment when you enable TLS in nginx/nginx.conf:
+      # Uncomment when you enable TLS in caddy/Caddyfile:
       # - "${HTTPS_PORT:-443}:443"
     volumes:
-      - ./nginx/nginx.conf:/etc/nginx/nginx.conf:ro,z
-      # TLS certs (fullchain.pem + privkey.pem). Read-only inside.
-      - ./puter/tls:/etc/nginx/tls:ro,z
+      - ./caddy/Caddyfile:/etc/caddy/Caddyfile:ro,z
+      # TLS certs (wildcard fullchain.pem + privkey.pem). Read-only inside.
+      - ./puter/tls:/etc/caddy/tls:ro,z
+      # Caddy's own state — the cert store it would use if you swap this
+      # config over to ACME. Kept under ./puter/data with everything else
+      # so one directory is the whole backup.
+      - ./puter/data/caddy:/data:z
     healthcheck:
-      test: ["CMD-SHELL", "wget -qO- --tries=1 --timeout=2 http://localhost/ || exit 1"]
+      # Hits Caddy's local-only admin API rather than proxying through to
+      # Puter: this reports whether the proxy itself is up and configured,
+      # and keeps working once the `:80` block becomes an HTTPS redirect.
+      # 127.0.0.1, not localhost — the admin endpoint is IPv4-only and
+      # busybox wget tries ::1 first.
+      test: ["CMD-SHELL", "wget -qO- --tries=1 --timeout=2 http://127.0.0.1:2019/config/ >/dev/null || exit 1"]
       interval: 10s
       timeout: 3s
       retries: 5

extensions/appTelemetry.test.ts

@@ -28,7 +28,7 @@ beforeAll(async () => {
 });
 
 afterAll(async () => {
-    await server.shutdown();
+    await server?.shutdown();
 });
 
 const seedOwnedApp = async (prefix: string) => {

extensions/devWatcher.test.ts

@@ -0,0 +1,555 @@
+import { mkdtempSync, rmSync, writeFileSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import path from 'node:path';
+import {
+    afterAll,
+    afterEach,
+    beforeAll,
+    beforeEach,
+    describe,
+    expect,
+    it,
+    vi,
+} from 'vitest';
+import { extensionStore } from '../src/backend/extensions.ts';
+import type { IConfig } from '../src/backend/types';
+import './devWatcher.ts';
+
+type Lifecycle = {
+    onServerStart: () => Promise<void>;
+    onServerShutdown: () => Promise<void>;
+};
+
+// The extension registers itself on import; that registry entry is the
+// only handle on the service class.
+const DevWatcherService = extensionStore.services.devWatcher as unknown as new (
+    config: IConfig,
+    clients: unknown,
+    stores: unknown,
+    services: unknown,
+) => Lifecycle;
+
+const makeService = (config: Record<string, unknown>): Lifecycle =>
+    new DevWatcherService(config as unknown as IConfig, {}, {}, {});
+
+let workdir: string;
+
+const write = (relative: string, contents: string): string => {
+    const abs = path.join(workdir, relative);
+    writeFileSync(abs, contents);
+    return abs;
+};
+
+/** Poll until `predicate` holds or the budget runs out. */
+const waitFor = async (
+    predicate: () => boolean,
+    label: string,
+    timeoutMs = 15_000,
+): Promise<void> => {
+    const start = Date.now();
+    while (Date.now() - start < timeoutMs) {
+        if (predicate()) return;
+        await new Promise((r) => setTimeout(r, 20));
+    }
+    throw new Error(`timed out waiting for ${label}`);
+};
+
+const logLines = (spy: { mock: { calls: unknown[][] } }): string[] =>
+    spy.mock.calls.map((call) => call.map(String).join(' '));
+
+describe('devWatcher extension', () => {
+    let log: ReturnType<typeof vi.spyOn>;
+    let warn: ReturnType<typeof vi.spyOn>;
+    let error: ReturnType<typeof vi.spyOn>;
+
+    beforeAll(() => {
+        workdir = mkdtempSync(path.join(tmpdir(), 'devwatch-test-'));
+    });
+
+    afterAll(() => {
+        rmSync(workdir, { recursive: true, force: true });
+        delete (extensionStore.services as Record<string, unknown>).devWatcher;
+    });
+
+    beforeEach(() => {
+        log = vi.spyOn(console, 'log').mockImplementation(() => {});
+        warn = vi.spyOn(console, 'warn').mockImplementation(() => {});
+        error = vi.spyOn(console, 'error').mockImplementation(() => {});
+    });
+
+    afterEach(() => {
+        log.mockRestore();
+        warn.mockRestore();
+        error.mockRestore();
+    });
+
+    const started = () =>
+        logLines(log).some((line) =>
+            line.startsWith('[devwatch] starting watchers from'),
+        );
+
+    // -- start gating -------------------------------------------------
+
+    it('does nothing when the server is not running in dev', async () => {
+        await makeService({ env: 'production' }).onServerStart();
+        expect(started()).toBe(false);
+    });
+
+    it('does nothing when devwatch is explicitly disabled', async () => {
+        await makeService({
+            env: 'dev',
+            devwatch: { enabled: false },
+        }).onServerStart();
+        expect(started()).toBe(false);
+    });
+
+    it('does nothing when the server opts out with no_devwatch', async () => {
+        await makeService({
+            env: 'dev',
+            no_devwatch: true,
+            devwatch: { enabled: true },
+        }).onServerStart();
+        expect(started()).toBe(false);
+    });
+
+    it('starts in dev even with no explicit devwatch block', async () => {
+        const service = makeService({
+            env: 'dev',
+            devwatch: {
+                root: workdir,
+                commands: [],
+                webpack: [],
+                ready_delay_ms: 0,
+            },
+        });
+        await service.onServerStart();
+        expect(started()).toBe(true);
+        await service.onServerShutdown();
+    });
+
+    it('starts outside dev when devwatch is explicitly enabled', async () => {
+        const service = makeService({
+            env: 'production',
+            devwatch: {
+                enabled: true,
+                root: workdir,
+                commands: [],
+                webpack: [],
+                ready_delay_ms: 0,
+            },
+        });
+        await service.onServerStart();
+        expect(started()).toBe(true);
+        await service.onServerShutdown();
+    });
+
+    it('ignores a devwatch config that is not an object', async () => {
+        // Falls back to `{}`, so the dev-env rule decides — and the
+        // default webpack entries would be used, so pin it off instead.
+        await makeService({
+            env: 'production',
+            devwatch: 'yes',
+        }).onServerStart();
+        expect(started()).toBe(false);
+    });
+
+    it('only starts once even if the lifecycle hook fires again', async () => {
+        const service = makeService({
+            env: 'dev',
+            devwatch: {
+                root: workdir,
+                commands: [],
+                webpack: [],
+                ready_delay_ms: 0,
+            },
+        });
+        await service.onServerStart();
+        await service.onServerStart();
+        expect(
+            logLines(log).filter((line) =>
+                line.startsWith('[devwatch] starting watchers from'),
+            ),
+        ).toHaveLength(1);
+        await service.onServerShutdown();
+    });
+
+    it('waits out the configured ready delay before resolving', async () => {
+        const service = makeService({
+            env: 'dev',
+            devwatch: {
+                root: workdir,
+                commands: [],
+                webpack: [],
+                ready_delay_ms: 60,
+            },
+        });
+        const start = Date.now();
+        await service.onServerStart();
+        expect(Date.now() - start).toBeGreaterThanOrEqual(50);
+        await service.onServerShutdown();
+    });
+
+    // -- child commands -----------------------------------------------
+
+    it('spawns a command, line-buffers its output and flushes the tail', async () => {
+        write(
+            'chatty.js',
+            [
+                "process.stdout.write('one\\ntwo\\n');",
+                "process.stderr.write('bad thing\\n');",
+                // No trailing newline: only the stream `end` flushes it.
+                "process.stdout.write('tail-no-newline');",
+            ].join('\n'),
+        );
+
+        const service = makeService({
+            env: 'dev',
+            devwatch: {
+                root: workdir,
+                commands: [
+                    {
+                        name: 'chatty',
+                        directory: '.',
+                        command: 'node',
+                        args: ['chatty.js'],
+                    },
+                ],
+                webpack: [],
+                ready_delay_ms: 0,
+            },
+        });
+        await service.onServerStart();
+
+        await waitFor(
+            () =>
+                logLines(log).some((l) =>
+                    l.includes('[devwatch:chatty:1] tail-no-newline'),
+                ),
+            'child stdout',
+        );
+
+        const lines = logLines(log);
+        expect(lines).toContain('[devwatch:chatty:1] one');
+        expect(lines).toContain('[devwatch:chatty:1] two');
+        expect(logLines(warn)).toContain('[devwatch:chatty:2] bad thing');
+
+        await waitFor(
+            () =>
+                logLines(log).some((l) =>
+                    l.includes('[devwatch:chatty:exit] process exited'),
+                ),
+            'child exit',
+        );
+        await service.onServerShutdown();
+    });
+
+    it('passes literal and computed env values to the child', async () => {
+        write(
+            'env.js',
+            'process.stdout.write(`STATIC=${process.env.STATIC_VALUE} ORIGIN=${process.env.FROM_CONFIG} MISSING=${process.env.BLOWS_UP}\\n`);',
+        );
+
+        const service = makeService({
+            env: 'dev',
+            origin: 'http://puter.localhost:4100',
+            devwatch: {
+                root: workdir,
+                commands: [
+                    {
+                        name: 'envtest',
+                        directory: '.',
+                        command: 'node',
+                        args: ['env.js'],
+                        env: {
+                            STATIC_VALUE: 'literal',
+                            FROM_CONFIG: ({
+                                global_config,
+                            }: {
+                                global_config: Record<string, unknown> | null;
+                            }) => String(global_config?.origin ?? ''),
+                            // Reading through a null is the "config not
+                            // loaded yet" shape the extension deliberately
+                            // stays quiet about.
+                            BLOWS_UP: () => {
+                                const nothing = null as unknown as {
+                                    x: string;
+                                };
+                                return nothing.x;
+                            },
+                            NOISY: () => {
+                                throw new Error('unexpected failure');
+                            },
+                        },
+                    },
+                ],
+                webpack: [],
+                ready_delay_ms: 0,
+            },
+        });
+        await service.onServerStart();
+
+        await waitFor(
+            () => logLines(log).some((l) => l.includes('STATIC=literal')),
+            'env output',
+        );
+        const line = logLines(log).find((l) => l.includes('STATIC=literal'))!;
+        expect(line).toContain('ORIGIN=http://puter.localhost:4100');
+        expect(line).toContain('MISSING=undefined');
+
+        // A null-property read is expected noise and stays silent; any
+        // other failure is reported.
+        const warnings = logLines(warn);
+        expect(
+            warnings.some((w) => w.includes('could not evaluate env function')),
+        ).toBe(true);
+        expect(warnings.some((w) => w.includes('for BLOWS_UP'))).toBe(false);
+        expect(warnings.some((w) => w.includes('for NOISY'))).toBe(true);
+
+        await service.onServerShutdown();
+    });
+
+    it('kills a still-running child on shutdown', async () => {
+        write('forever.js', 'setInterval(() => {}, 1000);');
+
+        const service = makeService({
+            env: 'dev',
+            devwatch: {
+                root: workdir,
+                commands: [
+                    {
+                        name: 'forever',
+                        directory: '.',
+                        command: 'node',
+                        args: ['forever.js'],
+                    },
+                ],
+                webpack: [],
+                ready_delay_ms: 0,
+            },
+        });
+        await service.onServerStart();
+        await service.onServerShutdown();
+
+        expect(logLines(log)).toContain('[devwatch:forever] stopping process');
+        await waitFor(
+            () =>
+                logLines(log).some((l) =>
+                    l.includes('[devwatch:forever:exit] process exited'),
+                ),
+            'child killed',
+        );
+    });
+
+    // -- webpack watchers ---------------------------------------------
+
+    const makeWebpackProject = (
+        name: string,
+        configFile: string,
+        contents: string,
+        packageJson?: string,
+    ): string => {
+        const dir = path.join(workdir, name);
+        rmSync(dir, { recursive: true, force: true });
+        writeFileSync(
+            path.join(
+                (() => {
+                    const { mkdirSync } =
+                        require('node:fs') as typeof import('node:fs');
+                    mkdirSync(path.join(dir, 'src'), { recursive: true });
+                    return dir;
+                })(),
+                'src/entry.js',
+            ),
+            "console.log('hello');\n",
+        );
+        writeFileSync(path.join(dir, configFile), contents);
+        if (packageJson) {
+            writeFileSync(path.join(dir, 'package.json'), packageJson);
+        }
+        return name;
+    };
+
+    it('compiles a CommonJS webpack config and reports later rebuilds', async () => {
+        const dir = makeWebpackProject(
+            'cjs-project',
+            'webpack.config.cjs',
+            `module.exports = {
+                mode: 'development',
+                entry: './src/entry.js',
+                output: { path: __dirname + '/out', filename: 'bundle.js' },
+            };`,
+        );
+
+        let onConfigSaw: Record<string, unknown> | undefined;
+        const service = makeService({
+            env: 'dev',
+            devwatch: {
+                root: workdir,
+                commands: [],
+                webpack: [
+                    {
+                        name: 'cjs',
+                        directory: dir,
+                        onConfig: (cfg: Record<string, unknown>) => {
+                            onConfigSaw = cfg;
+                        },
+                    },
+                ],
+                ready_delay_ms: 0,
+            },
+        });
+
+        await service.onServerStart();
+        expect(onConfigSaw).toBeDefined();
+        // The watcher context is anchored at <root>/<directory> so relative
+        // entries resolve regardless of the server's cwd.
+        expect(onConfigSaw!.context).toBe(path.join(workdir, dir));
+
+        // First build is silent by design; force a rebuild and assert the
+        // update line shows up.
+        await new Promise((r) => setTimeout(r, 500));
+        writeFileSync(
+            path.join(workdir, dir, 'src/entry.js'),
+            "console.log('hello again');\n",
+        );
+        await waitFor(
+            () =>
+                logLines(log).some((l) =>
+                    l.includes('[devwatch] updated cjs using Webpack'),
+                ),
+            'webpack rebuild',
+        );
+
+        await service.onServerShutdown();
+    });
+
+    it('resolves an ESM webpack config declared through package.json type', async () => {
+        const dir = makeWebpackProject(
+            'esm-project',
+            'webpack.config.js',
+            `export default {
+                mode: 'development',
+                entry: './src/entry.js',
+                output: { filename: 'bundle.js' },
+            };`,
+            JSON.stringify({ name: 'esm-project', type: 'module' }),
+        );
+
+        const service = makeService({
+            env: 'dev',
+            devwatch: {
+                root: workdir,
+                commands: [],
+                webpack: [{ directory: dir }],
+                ready_delay_ms: 0,
+            },
+        });
+
+        await service.onServerStart();
+        await service.onServerShutdown();
+        // Falling back to the directory as the display name is the
+        // documented behaviour when `name` is omitted.
+        expect(error).not.toHaveBeenCalled();
+    });
+
+    it('calls a config exported as a function and honours an explicit context', async () => {
+        const dir = makeWebpackProject(
+            'fn-project',
+            'webpack.config.cjs',
+            `module.exports = () => ({
+                mode: 'development',
+                context: 'src',
+                entry: './entry.js',
+                name: process.env.WEBPACK_MARKER,
+                output: { path: __dirname + '/out', filename: 'bundle.js' },
+            });`,
+        );
+
+        let seen: Record<string, unknown> | undefined;
+        const service = makeService({
+            env: 'dev',
+            devwatch: {
+                root: workdir,
+                commands: [],
+                webpack: [
+                    {
+                        name: 'fn',
+                        directory: dir,
+                        env: { WEBPACK_MARKER: 'set-during-load' },
+                        onConfig: (cfg: Record<string, unknown>) => {
+                            seen = cfg;
+                        },
+                    },
+                ],
+                ready_delay_ms: 0,
+            },
+        });
+
+        await service.onServerStart();
+        // Relative `context` resolves against <root>/<directory>.
+        expect(seen!.context).toBe(path.join(workdir, dir, 'src'));
+        // The entry's env map is applied while the config module runs, and
+        // restored afterwards.
+        expect(seen!.name).toBe('set-during-load');
+        expect(process.env.WEBPACK_MARKER).toBeUndefined();
+        await service.onServerShutdown();
+    });
+
+    it('reports a failing compilation instead of crashing the server', async () => {
+        const dir = makeWebpackProject(
+            'broken-project',
+            'webpack.config.cjs',
+            `module.exports = {
+                mode: 'development',
+                entry: './src/does-not-exist.js',
+                output: { path: __dirname + '/out', filename: 'bundle.js' },
+            };`,
+        );
+
+        const service = makeService({
+            env: 'dev',
+            devwatch: {
+                root: workdir,
+                commands: [],
+                webpack: [{ name: 'broken', directory: dir }],
+                ready_delay_ms: 0,
+            },
+        });
+
+        await service.onServerStart();
+        await waitFor(
+            () =>
+                logLines(error).some((l) =>
+                    l.includes('[devwatch] failed to update broken'),
+                ),
+            'webpack failure',
+        );
+        expect(
+            logLines(error).some((l) =>
+                l.includes('[devwatch] error information: broken'),
+            ),
+        ).toBe(true);
+        await service.onServerShutdown();
+    });
+
+    it('fails loudly when a directory has no webpack config at all', async () => {
+        const dir = path.join('no-config');
+        const { mkdirSync } = await import('node:fs');
+        mkdirSync(path.join(workdir, dir), { recursive: true });
+
+        const service = makeService({
+            env: 'dev',
+            devwatch: {
+                root: workdir,
+                commands: [],
+                webpack: [{ name: 'missing', directory: dir }],
+                ready_delay_ms: 0,
+            },
+        });
+
+        await expect(service.onServerStart()).rejects.toThrow(
+            'could not find webpack config for: no-config',
+        );
+        await service.onServerShutdown();
+    });
+});

extensions/installedApps.test.ts

@@ -38,7 +38,7 @@ beforeAll(async () => {
 });
 
 afterAll(async () => {
-    await server.shutdown();
+    await server?.shutdown();
 });
 
 const seedUser = async () => {

extensions/metering.test.ts

@@ -48,7 +48,7 @@ beforeAll(async () => {
 });
 
 afterAll(async () => {
-    await server.shutdown();
+    await server?.shutdown();
 });
 
 const seedUser = async () => {

extensions/serverInfo.test.ts

@@ -71,9 +71,7 @@ describe('serverInfo extension — handleServerInfo', () => {
         const statfsSpy = vi
             .spyOn(fs.default, 'statfs')
             .mockRejectedValue(new Error('statfs unsupported'));
-        const errSpy = vi
-            .spyOn(console, 'error')
-            .mockImplementation(() => {});
+        const errSpy = vi.spyOn(console, 'error').mockImplementation(() => {});
 
         const { res, captured } = makeRes();
         await handleServerInfo({} as Request, res);
@@ -88,4 +86,18 @@ describe('serverInfo extension — handleServerInfo', () => {
         statfsSpy.mockRestore();
         errSpy.mockRestore();
     });
+
+    it('reports an unknown CPU model when os.cpus() comes back empty', async () => {
+        const os = await import('node:os');
+        const cpusSpy = vi.spyOn(os.default, 'cpus').mockReturnValue([]);
+
+        const { res, captured } = makeRes();
+        await handleServerInfo({} as Request, res);
+
+        const cpu = captured.body!.cpu as Record<string, unknown>;
+        expect(cpu.model).toBe('Unknown');
+        expect(cpu.cores).toBe(0);
+
+        cpusSpy.mockRestore();
+    });
 });

extensions/thumbnails.test.ts

@@ -3,6 +3,7 @@ import {
     PutObjectCommand,
     type S3Client,
 } from '@aws-sdk/client-s3';
+import crypto from 'node:crypto';
 import {
     afterAll,
     beforeAll,
@@ -14,6 +15,7 @@ import {
 import { PuterServer } from '../src/backend/server.ts';
 import { setupTestServer } from '../src/backend/testUtil.ts';
 import {
+    handleFsCopyNodeThumbnail,
     handleFsRemoveNodeThumbnail,
     handleThumbnailCreated,
     handleThumbnailRead,
@@ -26,6 +28,9 @@ const TINY_PNG_BASE64 =
 
 const BUCKET = 'puter-local';
 
+// Keys the extension will accept back: its own `thumbnails/<uuid>` namespace.
+const mintedKey = () => `thumbnails/${crypto.randomUUID()}`;
+
 const streamToBuffer = async (
     body: { transformToByteArray: () => Promise<Uint8Array> } | undefined,
 ): Promise<Buffer> => {
@@ -41,7 +46,7 @@ describe('thumbnails extension — handleThumbnailCreated', () => {
     });
 
     afterAll(async () => {
-        await server.shutdown();
+        await server?.shutdown();
     });
 
     it('uploads a valid data: URL thumbnail to S3 and rewrites event.url to an s3:// pointer', async () => {
@@ -108,7 +113,7 @@ describe('thumbnails extension — handleThumbnailUploadPrepare', () => {
     });
 
     afterAll(async () => {
-        await server.shutdown();
+        await server?.shutdown();
     });
 
     it('returns early when event has no items array', async () => {
@@ -188,14 +193,14 @@ describe('thumbnails extension — handleThumbnailRead', () => {
     });
 
     afterAll(async () => {
-        await server.shutdown();
+        await server?.shutdown();
     });
 
     it('rewrites an s3:// thumbnail into a presigned https URL', async () => {
         // Seed an object so the presigned URL points at something real
         // (the signer itself doesn't validate existence, but this keeps
         // the test honest).
-        const key = 'thumb-read-test';
+        const key = mintedKey();
         await s3.send(
             new PutObjectCommand({
                 Bucket: BUCKET,
@@ -220,6 +225,57 @@ describe('thumbnails extension — handleThumbnailRead', () => {
         expect((entry.thumbnail as string).startsWith('http')).toBe(true);
     });
 
+    // `fsentries.thumbnail` is writable through the FS API, so a stored
+    // pointer is attacker input. Signing one the extension didn't mint would
+    // hand out a presigned read of an arbitrary object — including another
+    // user's file, whose key is its fsentry uuid in this same bucket.
+    it.each([
+        // Shaped exactly like an fs object key (and like a legacy thumbnail
+        // row) — indistinguishable from a planted pointer, so it fails closed.
+        [
+            "another user's file object",
+            `s3://${BUCKET}/${crypto.randomUUID()}`,
+        ],
+        [
+            'a key outside the thumbnails namespace',
+            `s3://${BUCKET}/secrets/dump`,
+        ],
+        [
+            'a namespace-lookalike key',
+            `s3://${BUCKET}/thumbnails/../${crypto.randomUUID()}`,
+        ],
+        ['a non-uuid inside the namespace', `s3://${BUCKET}/thumbnails/etc`],
+    ])('refuses to presign a pointer naming %s', async (_label, thumbnail) => {
+        const entry: Record<string, unknown> = { thumbnail };
+        await handleThumbnailRead(entry, {
+            s3,
+            s3Presign,
+            bucketName: BUCKET,
+            bucketEndpoint: 'http://127.0.0.1:4566/puter-local/',
+            db: stubDb,
+        });
+        expect(entry.thumbnail).toBeNull();
+    });
+
+    it('signs against its own bucket, ignoring the one in the pointer', async () => {
+        const key = mintedKey();
+        const entry: Record<string, unknown> = {
+            thumbnail: `s3://attacker-named-bucket/${key}`,
+        };
+        await handleThumbnailRead(entry, {
+            s3,
+            s3Presign,
+            bucketName: BUCKET,
+            bucketEndpoint: 'http://127.0.0.1:4566/puter-local/',
+            db: stubDb,
+        });
+        // Signed for OUR bucket; `attacker-named-bucket` never reached S3.
+        const signed = entry.thumbnail as string;
+        expect(signed.startsWith('http')).toBe(true);
+        expect(signed).not.toContain('attacker-named-bucket');
+        expect(signed).toContain(BUCKET);
+    });
+
     it('leaves the thumbnail untouched when not s3/https/data', async () => {
         const entry: Record<string, unknown> = { thumbnail: 'about:blank' };
         await handleThumbnailRead(entry, {
@@ -281,11 +337,11 @@ describe('thumbnails extension — handleFsRemoveNodeThumbnail', () => {
     });
 
     afterAll(async () => {
-        await server.shutdown();
+        await server?.shutdown();
     });
 
     it('deletes the S3 object referenced by an s3:// thumbnail URL', async () => {
-        const key = 'thumb-remove-test';
+        const key = mintedKey();
         await s3.send(
             new PutObjectCommand({
                 Bucket: BUCKET,
@@ -297,7 +353,7 @@ describe('thumbnails extension — handleFsRemoveNodeThumbnail', () => {
 
         await handleFsRemoveNodeThumbnail(
             { target: { thumbnail: `s3://${BUCKET}/${key}` } },
-            { s3 },
+            { s3, bucketName: BUCKET },
         );
 
         // GetObject should now error because the key was deleted.
@@ -306,15 +362,147 @@ describe('thumbnails extension — handleFsRemoveNodeThumbnail', () => {
         ).rejects.toThrow();
     });
 
+    // The destructive half of the same confused deputy: the stored pointer
+    // decides which object is deleted, so a key the extension didn't mint
+    // must never reach DeleteObject.
+    it('does not delete an object the pointer names but we did not mint', async () => {
+        const victimKey = crypto.randomUUID(); // shaped like an fs object key
+        await s3.send(
+            new PutObjectCommand({
+                Bucket: BUCKET,
+                Key: victimKey,
+                Body: Buffer.from(TINY_PNG_BASE64, 'base64'),
+                ContentType: 'image/png',
+            }),
+        );
+
+        await handleFsRemoveNodeThumbnail(
+            { target: { thumbnail: `s3://${BUCKET}/${victimKey}` } },
+            { s3, bucketName: BUCKET },
+        );
+
+        const survivor = await s3.send(
+            new GetObjectCommand({ Bucket: BUCKET, Key: victimKey }),
+        );
+        expect(survivor.ContentType).toBe('image/png');
+    });
+
     it('is a no-op when the target has no thumbnail', async () => {
         // Should not throw or attempt a delete.
-        await handleFsRemoveNodeThumbnail({ target: {} }, { s3 });
+        await handleFsRemoveNodeThumbnail(
+            { target: {} },
+            { s3, bucketName: BUCKET },
+        );
     });
 
     it('is a no-op when the thumbnail URL is not an s3:// pointer', async () => {
         await handleFsRemoveNodeThumbnail(
             { target: { thumbnail: 'https://cdn.example.com/x.png' } },
-            { s3 },
+            { s3, bucketName: BUCKET },
         );
     });
 });
+
+describe('thumbnails extension — handleFsCopyNodeThumbnail', () => {
+    let server: PuterServer;
+    let s3: S3Client;
+
+    beforeAll(async () => {
+        server = await setupTestServer();
+        s3 = server.clients.s3.get();
+    });
+
+    afterAll(async () => {
+        await server?.shutdown();
+    });
+
+    it('duplicates the shared thumbnail object and repoints the copied row', async () => {
+        const sourceKey = mintedKey();
+        const body = Buffer.from(TINY_PNG_BASE64, 'base64');
+        await s3.send(
+            new PutObjectCommand({
+                Bucket: BUCKET,
+                Key: sourceKey,
+                Body: body,
+                ContentType: 'image/png',
+            }),
+        );
+
+        const copyUuid = crypto.randomUUID();
+        const db = { write: vi.fn().mockResolvedValue(undefined) };
+        await handleFsCopyNodeThumbnail(
+            {
+                copy: {
+                    thumbnail: `s3://${BUCKET}/${sourceKey}`,
+                    uuid: copyUuid,
+                },
+            },
+            { s3, bucketName: BUCKET, db },
+        );
+
+        // The copied row was repointed at a fresh object...
+        expect(db.write).toHaveBeenCalledTimes(1);
+        const [, params] = db.write.mock.calls[0] as [string, [string, string]];
+        const [newPointer, updatedUuid] = params;
+        expect(updatedUuid).toBe(copyUuid);
+        expect(newPointer.startsWith(`s3://${BUCKET}/thumbnails/`)).toBe(true);
+        expect(newPointer).not.toBe(`s3://${BUCKET}/${sourceKey}`);
+
+        // ...whose content matches, while the source object survives — so
+        // deleting either entry can no longer break the other's thumbnail.
+        const newKey = newPointer.slice(`s3://${BUCKET}/`.length);
+        const duplicated = await s3.send(
+            new GetObjectCommand({ Bucket: BUCKET, Key: newKey }),
+        );
+        expect(
+            (await streamToBuffer(duplicated.Body as never)).equals(body),
+        ).toBe(true);
+        const original = await s3.send(
+            new GetObjectCommand({ Bucket: BUCKET, Key: sourceKey }),
+        );
+        expect(original.ContentType).toBe('image/png');
+    });
+
+    it('drops the pointer when the shared object is already gone', async () => {
+        const copyUuid = crypto.randomUUID();
+        const db = { write: vi.fn().mockResolvedValue(undefined) };
+        await handleFsCopyNodeThumbnail(
+            {
+                copy: {
+                    thumbnail: `s3://${BUCKET}/${mintedKey()}`, // never uploaded
+                    uuid: copyUuid,
+                },
+            },
+            { s3, bucketName: BUCKET, db },
+        );
+
+        expect(db.write).toHaveBeenCalledTimes(1);
+        const [sql, params] = db.write.mock.calls[0] as [string, [string]];
+        expect(sql).toContain('NULL');
+        expect(params).toEqual([copyUuid]);
+    });
+
+    it('does not duplicate an object the pointer names but we did not mint', async () => {
+        const foreignKey = crypto.randomUUID(); // shaped like an fs object key
+        const db = { write: vi.fn().mockResolvedValue(undefined) };
+        await handleFsCopyNodeThumbnail(
+            {
+                copy: {
+                    thumbnail: `s3://${BUCKET}/${foreignKey}`,
+                    uuid: crypto.randomUUID(),
+                },
+            },
+            { s3, bucketName: BUCKET, db },
+        );
+        expect(db.write).not.toHaveBeenCalled();
+    });
+
+    it('is a no-op when the copy has no thumbnail', async () => {
+        const db = { write: vi.fn().mockResolvedValue(undefined) };
+        await handleFsCopyNodeThumbnail(
+            { copy: { thumbnail: null, uuid: crypto.randomUUID() } },
+            { s3, bucketName: BUCKET, db },
+        );
+        expect(db.write).not.toHaveBeenCalled();
+    });
+});

extensions/thumbnails.ts

@@ -1,4 +1,5 @@
 import {
+    CopyObjectCommand,
     DeleteObjectCommand,
     GetObjectCommand,
     PutObjectCommand,
@@ -13,6 +14,54 @@ const clients = extension.import('client');
 const MAX_THUMBNAIL_BYTES = 2 * 1024 * 1024;
 const MAX_THUMBNAIL_PIXELS = 64e6;
 
+// Namespace every object this extension writes. An fs object's key is its
+// bare fsentry uuid and the default config points `thumbnailStore.name` at
+// the same bucket as `s3_bucket`, so without a prefix of our own there is no
+// way to tell a thumbnail we minted from any other object in the deployment.
+const THUMBNAIL_KEY_PREFIX = 'thumbnails/';
+const UUID_PATTERN =
+    /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i;
+
+const mintThumbnailKey = (): string =>
+    `${THUMBNAIL_KEY_PREFIX}${crypto.randomUUID()}`;
+
+/**
+ * Extract the object key from a stored thumbnail pointer, or null when the
+ * pointer isn't one this extension minted.
+ *
+ * `fsentries.thumbnail` is writable through the FS API, so neither half of the
+ * stored string is trusted: the bucket is discarded (callers always pass their
+ * own) and the key must sit under {@link THUMBNAIL_KEY_PREFIX} with a random
+ * uuid. Honouring an arbitrary key would lend this extension's storage
+ * credentials to whatever object the caller named — in the shared-bucket layout
+ * that is every user's file, since an fs object's key is its fsentry uuid.
+ * Legacy bare-uuid thumbnails fail the check and are treated as absent; they
+ * are indistinguishable from a planted pointer, so there is nothing safer to do
+ * with them than stop signing them.
+ */
+const resolveThumbnailKey = (pointer: string): string | null => {
+    let key: string;
+    if (pointer.startsWith('s3://')) {
+        const rest = pointer.slice('s3://'.length);
+        const slash = rest.indexOf('/');
+        if (slash === -1) return null;
+        key = rest.slice(slash + 1);
+    } else {
+        let pathname: string;
+        try {
+            pathname = new URL(pointer).pathname;
+        } catch {
+            return null;
+        }
+        const segments = pathname.replace(/^\/+/, '').split('/');
+        segments.shift(); // bucket
+        key = segments.join('/');
+    }
+    if (!key.startsWith(THUMBNAIL_KEY_PREFIX)) return null;
+    const id = key.slice(THUMBNAIL_KEY_PREFIX.length);
+    return UUID_PATTERN.test(id) ? key : null;
+};
+
 // S3 client + bucket config — lazily resolved after boot from config.
 let s3Client: S3Client | null = null;
 let s3PresignClient: S3Client | null = null;
@@ -112,7 +161,7 @@ export async function handleThumbnailCreated(
         return;
     }
 
-    const key = crypto.randomUUID();
+    const key = mintThumbnailKey();
     event.url = `s3://${deps.bucketName}/${key}`;
 
     await deps.s3.send(
@@ -151,7 +200,7 @@ export const handleThumbnailUploadPrepare = async (
                 continue;
         }
 
-        const key = crypto.randomUUID();
+        const key = mintThumbnailKey();
         const command = new PutObjectCommand({
             Bucket: deps.bucketName,
             Key: key,
@@ -178,27 +227,27 @@ export const handleThumbnailRead = async (
     if (typeof thumb !== 'string' || !thumb) return;
     const presignClient = deps.s3Presign;
 
-    if (thumb.startsWith('s3://')) {
-        const [bucket, key] = thumb.slice(5).split('/');
-        entry.thumbnail = await getSignedUrl(
-            presignClient,
-            new GetObjectCommand({ Bucket: bucket, Key: key }),
-            { expiresIn: 604800 },
-        );
-    } else if (
-        thumb.startsWith('https') &&
-        thumb.includes(new URL(deps.bucketEndpoint).hostname)
-    ) {
+    if (
+        thumb.startsWith('s3://') ||
         // Legacy format — remove after full migration
-        const [bucket, key] = new URL(thumb).pathname.slice(1).split('/');
+        (thumb.startsWith('https') &&
+            thumb.includes(new URL(deps.bucketEndpoint).hostname))
+    ) {
+        const key = resolveThumbnailKey(thumb);
+        if (!key) {
+            // Not a pointer we minted — refuse to sign it rather than hand
+            // out a presigned read of whatever object it names.
+            entry.thumbnail = null;
+            return;
+        }
         entry.thumbnail = await getSignedUrl(
             presignClient,
-            new GetObjectCommand({ Bucket: bucket, Key: key }),
+            new GetObjectCommand({ Bucket: deps.bucketName, Key: key }),
             { expiresIn: 604800 },
         );
     } else if (thumb.startsWith('data')) {
         // Inline data-URL migration: upload to S3 and update the DB entry.
-        const key = crypto.randomUUID();
+        const key = mintThumbnailKey();
         const { mimeType, data } = base64ParseDataUrl(thumb);
         const newUrl = `s3://${deps.bucketName}/${key}`;
 
@@ -232,15 +281,72 @@ export const handleThumbnailRead = async (
     }
 };
 
-export const handleFsRemoveNodeThumbnail = async (
-    payload: { target: Record<string, unknown> },
-    deps: { s3: S3Client },
+export const handleFsCopyNodeThumbnail = async (
+    payload: { copy?: { thumbnail?: string | null; uuid?: string } | null },
+    deps: {
+        s3: S3Client;
+        bucketName: string;
+        db: { write: (sql: string, params: unknown[]) => Promise<unknown> };
+    },
 ): Promise<void> => {
-    const thumbnailUrl = payload.target.thumbnail as string | undefined;
-    if (!thumbnailUrl || !thumbnailUrl.startsWith('s3://')) return;
+    const copy = payload.copy;
+    const thumbnailUrl = copy?.thumbnail;
+    if (!copy || !copy.uuid || typeof thumbnailUrl !== 'string') return;
 
-    const [bucket, key] = thumbnailUrl.slice(5).split('/');
-    await deps.s3.send(new DeleteObjectCommand({ Bucket: bucket, Key: key }));
+    // Same trust rule as the read and remove paths: only touch objects this
+    // extension minted.
+    const sourceKey = resolveThumbnailKey(thumbnailUrl);
+    if (!sourceKey) return;
+
+    // The copied row points at the SAME S3 object as its source, and
+    // fs.remove.node deletes the pointed-to object — so the first removal
+    // among the sharers (an overwrite, a trash purge) would break every
+    // other sharer's thumbnail. Give the copy an object of its own.
+    const newKey = mintThumbnailKey();
+    try {
+        await deps.s3.send(
+            new CopyObjectCommand({
+                Bucket: deps.bucketName,
+                CopySource: `${deps.bucketName}/${sourceKey}`,
+                Key: newKey,
+            }),
+        );
+    } catch (err) {
+        // The shared object is already gone (e.g. a sharer was removed
+        // before this fix existed) — the pointer is dead either way, so
+        // drop it rather than leave the row advertising a thumbnail it
+        // doesn't have.
+        await deps.db.write(
+            'UPDATE `fsentries` SET `thumbnail` = NULL WHERE `uuid` = ?',
+            [copy.uuid],
+        );
+        console.warn('[thumbnails] failed to duplicate thumbnail on copy', err);
+        return;
+    }
+
+    await deps.db.write(
+        'UPDATE `fsentries` SET `thumbnail` = ? WHERE `uuid` = ?',
+        [`s3://${deps.bucketName}/${newKey}`, copy.uuid],
+    );
+};
+
+export const handleFsRemoveNodeThumbnail = async (
+    payload: { target: { thumbnail?: string | null } },
+    deps: { s3: S3Client; bucketName: string },
+): Promise<void> => {
+    const thumbnailUrl = payload.target.thumbnail;
+    if (!thumbnailUrl) return;
+
+    // Same trust rule as the read path, and load-bearing for the same reason:
+    // the pointer decides which object gets deleted, so a key we didn't mint
+    // would let the owner of one file destroy an object belonging to someone
+    // else just by naming it here.
+    const key = resolveThumbnailKey(thumbnailUrl);
+    if (!key) return;
+
+    await deps.s3.send(
+        new DeleteObjectCommand({ Bucket: deps.bucketName, Key: key }),
+    );
 };
 
 extension.on(
@@ -279,12 +385,29 @@ extension.on('thumbnail.read', async (_key, entry: Record<string, unknown>) => {
     });
 });
 
+// -- fs.copy.node ----------------------------------------------------
+// A copied entry initially shares its source's thumbnail object; duplicate
+// it so removing either entry can't break the other's thumbnail.
+
+extension.on('fs.copy.node', async (_key, payload) => {
+    await handleFsCopyNodeThumbnail(
+        payload as {
+            copy?: { thumbnail?: string | null; uuid?: string } | null;
+        },
+        {
+            s3: getClient(),
+            bucketName: thumbnailBucketName,
+            db: clients.db,
+        },
+    );
+});
+
 // -- fs.remove.node --------------------------------------------------
 // Delete S3 thumbnail when the file is removed.
 
-extension.on(
-    'fs.remove.node',
-    async (_key, payload: { target: Record<string, unknown> }) => {
-        await handleFsRemoveNodeThumbnail(payload, { s3: getClient() });
-    },
-);
+extension.on('fs.remove.node', async (_key, payload) => {
+    await handleFsRemoveNodeThumbnail(payload, {
+        s3: getClient(),
+        bucketName: thumbnailBucketName,
+    });
+});

extensions/whoami.test.ts

@@ -51,7 +51,7 @@ beforeAll(async () => {
 });
 
 afterAll(async () => {
-    await server.shutdown();
+    await server?.shutdown();
 });
 
 const seedUser = async () => {

install.ps1

@@ -11,7 +11,7 @@
 # What this does, in order:
 #   1. Checks that docker (with the compose plugin) exists.
 #   2. Creates ./puter-selfhosted/ (override with $env:PUTER_DIR).
-#   3. Downloads docker-compose.yml + nginx.conf from the OSS repo.
+#   3. Downloads docker-compose.yml + caddy/Caddyfile from the OSS repo.
 #   4. Generates fresh secrets and writes .env + puter/config/config.json.
 #   5. Runs `docker compose up -d` and prints how to find the admin password.
 #
@@ -23,7 +23,7 @@
 #   PUTER_DIR     install directory                       (default: ./puter-selfhosted)
 #   PUTER_URL     base URL to fetch docker-compose.yml    (default: GitHub raw, main branch)
 #   PUTER_DOMAIN  domain Puter will serve on              (default: puter.localhost)
-#   PUTER_PORT    HTTP port for nginx                     (default: 80)
+#   PUTER_PORT    HTTP port for Caddy                     (default: 80)
 #   PUTER_FORCE   set to 1 to overwrite existing .env / config.json
 
 [CmdletBinding()]
@@ -77,10 +77,10 @@ if ($LASTEXITCODE -ne 0) {
 # ── Step 2: install dir ─────────────────────────────────────────────
 $null = New-Item -ItemType Directory -Force -Path $PuterDir
 Set-Location $PuterDir
-$null = New-Item -ItemType Directory -Force -Path 'puter/config', 'puter/data', 'puter/tls'
+$null = New-Item -ItemType Directory -Force -Path 'puter/config', 'puter/data', 'puter/data/caddy', 'puter/tls'
 Write-Log "install dir: $((Get-Location).Path)"
 
-# ── Step 3: docker-compose.yml + nginx config ──────────────────────
+# ── Step 3: docker-compose.yml + Caddy config ──────────────────────
 Write-Log "downloading docker-compose.yml from $PuterUrl"
 try {
     Invoke-WebRequest -Uri "$PuterUrl/docker-compose.yml" -OutFile 'docker-compose.yml' -UseBasicParsing
@@ -88,17 +88,19 @@ try {
     Die "could not fetch $PuterUrl/docker-compose.yml — $_"
 }
 
-Write-Log "downloading nginx/nginx.conf from $PuterUrl"
-$null = New-Item -ItemType Directory -Force -Path 'nginx'
+# The Caddyfile is domain-agnostic — it answers on every Host and leaves
+# the subdomain routing to Puter — so there's nothing to template in.
+Write-Log "downloading caddy/Caddyfile from $PuterUrl"
+$null = New-Item -ItemType Directory -Force -Path 'caddy'
 # If the path was previously auto-created as a directory by a failed
 # `compose up`, remove it so we can write the file there.
-if (Test-Path 'nginx/nginx.conf' -PathType Container) {
-    Remove-Item 'nginx/nginx.conf' -Recurse -Force
+if (Test-Path 'caddy/Caddyfile' -PathType Container) {
+    Remove-Item 'caddy/Caddyfile' -Recurse -Force
 }
 try {
-    Invoke-WebRequest -Uri "$PuterUrl/nginx/nginx.conf" -OutFile 'nginx/nginx.conf' -UseBasicParsing
+    Invoke-WebRequest -Uri "$PuterUrl/caddy/Caddyfile" -OutFile 'caddy/Caddyfile' -UseBasicParsing
 } catch {
-    Die "could not fetch $PuterUrl/nginx/nginx.conf — $_"
+    Die "could not fetch $PuterUrl/caddy/Caddyfile — $_"
 }
 
 # ── Step 4: secrets, .env, config.json ──────────────────────────────
@@ -121,7 +123,8 @@ if ($writeConfig) {
 
     $envContent = @"
 HTTP_PORT=$PuterPort
-# HTTPS_PORT=443     # uncomment after enabling TLS (see doc/selfhosting/full-stack.md)
+# HTTPS_PORT=443     # uncomment after enabling TLS in caddy/Caddyfile
+#                    # (see "Step 3 — TLS" in doc/self-hosting.md)
 
 MARIADB_ROOT_PASSWORD=$mariadbRootPw
 MARIADB_DATABASE=puter
@@ -205,4 +208,4 @@ Write-Log "    cd $PuterDir; docker compose logs -f puter"
 Write-Log ''
 Write-Log "open http://${PuterDomain}:${PuterPort} once the puter container is healthy."
 Write-Log 'first-boot admin password is logged once — grab it with:'
-Write-Log "    cd $PuterDir; docker compose logs puter | Select-String password"
+Write-Log "    cd $PuterDir; docker compose logs puter | Select-String password"

install.sh

@@ -7,7 +7,8 @@
 # What this does, in order:
 #   1. Checks that docker (with the compose plugin), curl, and openssl exist.
 #   2. Creates ./puter-selfhosted/ (override with PUTER_DIR=...).
-#   3. Downloads docker-compose.yml from the OSS repo (raw.githubusercontent.com).
+#   3. Downloads docker-compose.yml + caddy/Caddyfile from the OSS repo
+#      (raw.githubusercontent.com).
 #   4. Generates fresh secrets and writes .env + puter/config/config.json.
 #   5. Runs `docker compose up -d` and prints the first-boot admin password.
 #
@@ -19,15 +20,17 @@
 #   PUTER_DIR         install directory                   (default: ./puter-selfhosted)
 #   PUTER_URL         base URL to fetch docker-compose.yml (default: GitHub raw, main branch)
 #   PUTER_DOMAIN      domain Puter will serve on           (default: puter.localhost)
-#   PUTER_PORT        HTTP port for nginx                  (default: 80)
+#   PUTER_PORT        HTTP port for Caddy                  (default: 80)
 #   PUTER_PROTOCOL    public scheme: http | https          (default: http)
-#                     Set https when a TLS-terminating reverse proxy (Caddy,
-#                     Traefik, nginx, a cloud LB) sits in front — Puter then
-#                     builds https:// origins, S3 URLs, and redirects. See
-#                     "Running behind your own reverse proxy" in doc/self-hosting.md.
+#                     Set https once TLS is terminating in front of Puter —
+#                     either the bundled Caddy with your certs (see "Step 3 —
+#                     TLS" in doc/self-hosting.md) or your own proxy (Traefik,
+#                     a cloud LB). Puter then builds https:// origins, S3
+#                     URLs, and redirects. Leave it http and the installer
+#                     serves plain HTTP on PUTER_PORT.
 #   PUTER_TRUST_PROXY number of reverse-proxy hops in front (default: 1)
-#                     1 = the bundled nginx (or a single external proxy);
-#                     2 = two hops (e.g. Cloudflare → your proxy → Puter).
+#                     1 = the bundled Caddy (or a single external proxy);
+#                     2 = two hops (e.g. Cloudflare → Caddy → Puter).
 #   PUTER_ENV         prod | dev                            (default: prod)
 #   PUTER_FORCE       set to 1 to overwrite existing .env / config.json
 
@@ -72,25 +75,27 @@ mkdir -p puter/config puter/data puter/tls
 # bind-mount roots sidesteps the mismatch without guessing each image's
 # internal UID. (Docker Desktop on macOS/Windows papers over this with
 # its VM layer; native Linux docker on Debian/Alpine doesn't.)
-mkdir -p puter/data/valkey puter/data/mariadb puter/data/dynamo puter/data/s3 puter/data/puter
-chmod 0777 puter/data/valkey puter/data/mariadb puter/data/dynamo puter/data/s3 puter/data/puter
+mkdir -p puter/data/valkey puter/data/mariadb puter/data/dynamo puter/data/s3 puter/data/puter puter/data/caddy
+chmod 0777 puter/data/valkey puter/data/mariadb puter/data/dynamo puter/data/s3 puter/data/puter puter/data/caddy
 log "install dir: $(pwd)"
 
-# ── Step 3: docker-compose.yml + nginx config ──────────────────────
+# ── Step 3: docker-compose.yml + Caddy config ──────────────────────
 log "downloading docker-compose.yml from $PUTER_URL"
 curl -fsSL "$PUTER_URL/docker-compose.yml" -o docker-compose.yml \
     || die "could not fetch $PUTER_URL/docker-compose.yml"
 
-# nginx is mounted as `./nginx/nginx.conf:/etc/nginx/nginx.conf:ro` — if
+# Caddy is mounted as `./caddy/Caddyfile:/etc/caddy/Caddyfile:ro,z` — if
 # the host file is missing, docker silently creates a directory at that
 # path and the mount fails with "not a directory" at container start.
-log "downloading nginx/nginx.conf from $PUTER_URL"
-mkdir -p nginx
+# The Caddyfile is domain-agnostic — it answers on every Host and leaves
+# the subdomain routing to Puter — so there's nothing to template in.
+log "downloading caddy/Caddyfile from $PUTER_URL"
+mkdir -p caddy
 # If the path was previously auto-created as a dir by a failed `compose up`,
 # remove it so curl can write the file.
-[ -d nginx/nginx.conf ] && rmdir nginx/nginx.conf 2>/dev/null || true
-curl -fsSL "$PUTER_URL/nginx/nginx.conf" -o nginx/nginx.conf \
-    || die "could not fetch $PUTER_URL/nginx/nginx.conf"
+[ -d caddy/Caddyfile ] && rmdir caddy/Caddyfile 2>/dev/null || true
+curl -fsSL "$PUTER_URL/caddy/Caddyfile" -o caddy/Caddyfile \
+    || die "could not fetch $PUTER_URL/caddy/Caddyfile"
 
 # ── Step 4: secrets, .env, config.json ──────────────────────────────
 write_config=1
@@ -113,7 +118,8 @@ if [ "$write_config" = "1" ]; then
 
     cat > .env <<EOF
 HTTP_PORT=$PUTER_PORT
-# HTTPS_PORT=443     # uncomment after enabling TLS (see doc/selfhosting/full-stack.md)
+# HTTPS_PORT=443     # uncomment after enabling TLS in caddy/Caddyfile
+#                    # (see "Step 3 — TLS" in doc/self-hosting.md)
 
 MARIADB_ROOT_PASSWORD=$MARIADB_ROOT_PASSWORD
 MARIADB_DATABASE=puter
@@ -190,6 +196,18 @@ EOF
 EOF
 fi
 
+# `https` only works if something in front is actually terminating it. The
+# bundled Caddy does that from ./puter/tls once you enable its `:443` block
+# (see "Step 3 — TLS" in doc/self-hosting.md); your own edge proxy is fine
+# too. Neither in place means Puter hands out https:// URLs for an endpoint
+# that only speaks HTTP — broken logins and mixed content.
+if [ "$PUTER_PROTOCOL" = "https" ] && [ ! -f puter/tls/fullchain.pem ]; then
+    warn "PUTER_PROTOCOL=https but ./puter/tls/fullchain.pem is missing."
+    warn "The bundled Caddy is still serving plain HTTP on port $PUTER_PORT."
+    warn "Either drop a wildcard cert into ./puter/tls and uncomment the :443"
+    warn "block in caddy/Caddyfile, or terminate TLS in your own proxy."
+fi
+
 # ── Step 5: bring it up ─────────────────────────────────────────────
 log "docker compose up -d"
 docker compose up -d

nginx/nginx.conf

@@ -1,135 +0,0 @@
-# Reverse proxy in front of Puter — mirrors what the prod ALB does:
-# accepts every Host header, forwards to the Puter container, and lets
-# the Puter app handle subdomain-based routing internally (api.*,
-# site.*, app.*, etc).
-#
-# To enable TLS:
-#   1. Drop your fullchain.pem + privkey.pem into ./puter/tls/.
-#   2. Uncomment the 443 server{} block below.
-#   3. Update server_name to your domain (and wildcard subdomains).
-
-worker_processes auto;
-events {
-    worker_connections 4096;
-}
-
-http {
-    # Required for Puter's WebSocket / socket.io upgrades.
-    map $http_upgrade $connection_upgrade {
-        default upgrade;
-        '' close;
-    }
-
-    # Rough size cap that mirrors prod ALB defaults; tune for your
-    # uploads. Puter chunks large uploads, so 1 GiB per request is plenty.
-    client_max_body_size 1024m;
-    proxy_read_timeout 600s;
-    proxy_send_timeout 600s;
-    proxy_buffering off;
-    server_tokens off;
-
-    upstream puter_backend {
-        server puter:4100;
-        keepalive 32;
-    }
-
-    upstream s3_backend {
-        # RustFS — see `s3` service in docker-compose.full.yml. Browsers
-        # PUT/GET here for presigned-URL uploads / downloads. Routed via
-        # the `s3.<domain>` subdomain so signature verification works
-        # (Host header preserved end-to-end) and so HTTPS stays clean
-        # (no mixed-content from a port-9000 host publish).
-        server s3:9000;
-        keepalive 32;
-    }
-
-    # ── HTTP (port 80) ─────────────────────────────────────────────
-    server {
-        listen 80;
-        listen [::]:80;
-        server_name ~^s3\.;
-
-        location / {
-            proxy_pass http://s3_backend;
-            proxy_http_version 1.1;
-            # Critical: preserve the original Host so RustFS validates
-            # the request against the same host the URL was signed for.
-            proxy_set_header Host $host;
-            proxy_set_header X-Real-IP $remote_addr;
-            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
-            proxy_set_header X-Forwarded-Proto $scheme;
-        }
-    }
-
-    server {
-        listen 80 default_server;
-        listen [::]:80 default_server;
-        server_name _;
-
-        # Note: when you enable TLS, replace this block with a redirect:
-        #   return 301 https://$host$request_uri;
-        location / {
-            proxy_pass http://puter_backend;
-            proxy_http_version 1.1;
-            proxy_set_header Host $host;
-            proxy_set_header X-Real-IP $remote_addr;
-            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
-            proxy_set_header X-Forwarded-Proto $scheme;
-            proxy_set_header X-Forwarded-Host $host;
-            proxy_set_header X-Forwarded-Port $server_port;
-            proxy_set_header Upgrade $http_upgrade;
-            proxy_set_header Connection $connection_upgrade;
-        }
-    }
-
-    # ── HTTPS (port 443) — uncomment after dropping certs in ./puter/tls/ ─
-    # server {
-    #     listen 443 ssl;
-    #     listen [::]:443 ssl;
-    #     http2 on;
-    #     server_name ~^s3\.;
-    #
-    #     ssl_certificate     /etc/nginx/tls/fullchain.pem;
-    #     ssl_certificate_key /etc/nginx/tls/privkey.pem;
-    #     ssl_protocols       TLSv1.2 TLSv1.3;
-    #     ssl_ciphers         HIGH:!aNULL:!MD5;
-    #     ssl_session_cache   shared:SSL:10m;
-    #     ssl_session_timeout 10m;
-    #
-    #     location / {
-    #         proxy_pass http://s3_backend;
-    #         proxy_http_version 1.1;
-    #         proxy_set_header Host $host;
-    #         proxy_set_header X-Real-IP $remote_addr;
-    #         proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
-    #         proxy_set_header X-Forwarded-Proto $scheme;
-    #     }
-    # }
-    #
-    # server {
-    #     listen 443 ssl default_server;
-    #     listen [::]:443 ssl default_server;
-    #     http2 on;
-    #     server_name _;
-    #
-    #     ssl_certificate     /etc/nginx/tls/fullchain.pem;
-    #     ssl_certificate_key /etc/nginx/tls/privkey.pem;
-    #     ssl_protocols       TLSv1.2 TLSv1.3;
-    #     ssl_ciphers         HIGH:!aNULL:!MD5;
-    #     ssl_session_cache   shared:SSL:10m;
-    #     ssl_session_timeout 10m;
-    #
-    #     location / {
-    #         proxy_pass http://puter_backend;
-    #         proxy_http_version 1.1;
-    #         proxy_set_header Host $host;
-    #         proxy_set_header X-Real-IP $remote_addr;
-    #         proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
-    #         proxy_set_header X-Forwarded-Proto $scheme;
-    #         proxy_set_header X-Forwarded-Host $host;
-    #         proxy_set_header X-Forwarded-Port $server_port;
-    #         proxy_set_header Upgrade $http_upgrade;
-    #         proxy_set_header Connection $connection_upgrade;
-    #     }
-    # }
-}

package-lock.json

@@ -1304,7 +1304,6 @@
     },
     "node_modules/@clack/prompts/node_modules/is-unicode-supported": {
       "version": "1.3.0",
-      "extraneous": true,
       "inBundle": true,
       "license": "MIT",
       "engines": {
@@ -9933,6 +9932,40 @@
         "node": ">=10.2.0"
       }
     },
+    "node_modules/engine.io-client": {
+      "version": "6.5.4",
+      "resolved": "https://registry.npmjs.org/engine.io-client/-/engine.io-client-6.5.4.tgz",
+      "integrity": "sha512-GeZeeRjpD2qf49cZQ0Wvh/8NJNfeXkXXcoGh+F77oEAgo9gUHwT1fCRxSNU+YEEaysOJTnsFHmM5oAcPy4ntvQ==",
+      "license": "MIT",
+      "dependencies": {
+        "@socket.io/component-emitter": "~3.1.0",
+        "debug": "~4.3.1",
+        "engine.io-parser": "~5.2.1",
+        "ws": "~8.17.1",
+        "xmlhttprequest-ssl": "~2.0.0"
+      }
+    },
+    "node_modules/engine.io-client/node_modules/ws": {
+      "version": "8.17.1",
+      "resolved": "https://registry.npmjs.org/ws/-/ws-8.17.1.tgz",
+      "integrity": "sha512-6XQFvXTkbfUOZOKKILFG1PDK2NDQs4azKQl26T0YS5CxqWLgXajbPZ+h4gZekJyRqFU8pvnbAbbs/3TgRPy+GQ==",
+      "license": "MIT",
+      "engines": {
+        "node": ">=10.0.0"
+      },
+      "peerDependencies": {
+        "bufferutil": "^4.0.1",
+        "utf-8-validate": ">=5.0.2"
+      },
+      "peerDependenciesMeta": {
+        "bufferutil": {
+          "optional": true
+        },
+        "utf-8-validate": {
+          "optional": true
+        }
+      }
+    },
     "node_modules/engine.io-parser": {
       "version": "5.2.3",
       "resolved": "https://registry.npmjs.org/engine.io-parser/-/engine.io-parser-5.2.3.tgz",
@@ -15468,6 +15501,12 @@
         "tslib": "^2.0.3"
       }
     },
+    "node_modules/path-browserify": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/path-browserify/-/path-browserify-1.0.1.tgz",
+      "integrity": "sha512-b7uo2UCUOYZcnF/3ID0lulOJi/bafxa1xPe7ZPsammBSpjSWQkjNxlt635YGS2MiR9GjvuXCtz2emr3jbsz98g==",
+      "license": "MIT"
+    },
     "node_modules/path-exists": {
       "version": "4.0.0",
       "resolved": "https://registry.npmjs.org/path-exists/-/path-exists-4.0.0.tgz",
@@ -17299,6 +17338,21 @@
         }
       }
     },
+    "node_modules/socket.io-client": {
+      "version": "4.7.2",
+      "resolved": "https://registry.npmjs.org/socket.io-client/-/socket.io-client-4.7.2.tgz",
+      "integrity": "sha512-vtA0uD4ibrYD793SOIAwlo8cj6haOeMHrGvwPxJsxH7CeIksqJ+3Zc06RvWTIFgiSqx4A3sOnTXpfAEE2Zyz6w==",
+      "license": "MIT",
+      "dependencies": {
+        "@socket.io/component-emitter": "~3.1.0",
+        "debug": "~4.3.2",
+        "engine.io-client": "~6.5.2",
+        "socket.io-parser": "~4.2.4"
+      },
+      "engines": {
+        "node": ">=10.0.0"
+      }
+    },
     "node_modules/socket.io-parser": {
       "version": "4.2.6",
       "resolved": "https://registry.npmjs.org/socket.io-parser/-/socket.io-parser-4.2.6.tgz",
@@ -19190,6 +19244,14 @@
       "integrity": "sha512-JZnDKK8B0RCDw84FNdDAIpZK+JuJw+s7Lz8nksI7SIuU3UXJJslUthsi+uWBUYOwPFwW7W7PRLRfUKpxjtjFCw==",
       "license": "MIT"
     },
+    "node_modules/xmlhttprequest-ssl": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/xmlhttprequest-ssl/-/xmlhttprequest-ssl-2.0.0.tgz",
+      "integrity": "sha512-QKxVRxiRACQcVuQEYFsI1hhkrMlrXHPegbbd1yn9UHOmRxY+si12nQYzri3vbzt8VdTTRviqcKxcyllFas5z2A==",
+      "engines": {
+        "node": ">=0.4.0"
+      }
+    },
     "node_modules/xtend": {
       "version": "4.0.2",
       "resolved": "https://registry.npmjs.org/xtend/-/xtend-4.0.2.tgz",
@@ -20194,7 +20256,9 @@
       "license": "Apache-2.0",
       "dependencies": {
         "@heyputer/kv.js": "^0.2.1",
-        "open": "^10.2.0"
+        "open": "^10.2.0",
+        "path-browserify": "1.0.1",
+        "socket.io-client": "4.7.2"
       },
       "devDependencies": {
         "@playwright/test": "^1.49.0",

package.json

@@ -1,6 +1,6 @@
 {
   "name": "puter.com",
-  "version": "2.5.1",
+  "version": "26.07",
   "author": "Puter Technologies Inc.",
   "license": "AGPL-3.0-only",
   "description": "Desktop environment in the browser!",
@@ -51,8 +51,8 @@
     "yaml": "^2.8.1"
   },
   "scripts": {
-    "test:backend": "npm run setupExtensions && vitest run --config src/backend/vitest.config.ts ",
-    "test:backend:postgres": "npm run setupExtensions && PUTER_TEST_DB_ENGINE=postgres vitest run --config src/backend/vitest.config.ts ",
+    "test:backend": "npm run setupExtensions && npm run build:workerLib && vitest run --config src/backend/vitest.config.ts ",
+    "test:backend:postgres": "npm run setupExtensions && npm run build:workerLib && PUTER_TEST_DB_ENGINE=postgres vitest run --config src/backend/vitest.config.ts ",
     "test:puterjs": "npm run setupExtensions && vitest run --config src/puter-js/tests/api/vitest.config.ts",
     "test:puterjs:node": "npm run test:puterjs -- src/puter-js/tests/api/runners/node.test.ts",
     "test:puterjs:browser": "npm run test:puterjs -- src/puter-js/tests/api/runners/browser.test.ts",
@@ -60,8 +60,7 @@
     "test:puterjs:coverage": "npm run build:workerLib:coverage && npm run setupExtensions && rm -rf src/puter-js/coverage && PUTER_COVERAGE=1 vitest run --config src/puter-js/tests/api/vitest.config.ts && node ./tools/puterjsCoverageReport.mjs",
     "build:workerLib:coverage": "cd src/puter-js && npm run build:coverage && cd ../worker && npm run build",
     "start:gui": "nodemon --exec \"node dev-server.js\" ",
-    "start": "node --enable-source-maps -r ./dist/src/backend/telemetry.js ./dist/src/backend/index.js",
-    "prestart": "npm run setupExtensions && npm run build:ts",
+    "start": "node ./tools/start.mjs",
     "dev": "npm start",
     "build": "npm run setupExtensions && npm run build:ts && cd src/gui && node ./build.js && cd ../puter-js && npm run build",
     "build:workerLib": "cd src/puter-js && npm run build && cd ../worker && npm run build",

src/backend/clients/alarm/AlarmClient.test.ts

@@ -0,0 +1,503 @@
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import { AlarmClient } from './AlarmClient';
+import type { IConfig, IPagerConfig } from '../../types';
+import type { AlertPayload } from './types';
+
+const pdEvent = vi.hoisted(() => vi.fn(async () => ({})));
+vi.mock('@pagerduty/pdjs', () => ({ event: pdEvent }));
+
+const makeClient = (pager: IPagerConfig = {}) =>
+    new AlarmClient({ serverId: 'test-node', pager } as unknown as IConfig);
+
+/** Register a capturing handler in place of a real transport. */
+const capture = (
+    client: AlarmClient,
+    minSeverity?: 'critical' | 'error' | 'warning' | 'info',
+    maxSeverity?: 'critical' | 'error' | 'warning' | 'info',
+) => {
+    const seen: AlertPayload[] = [];
+    client.addAlertHandler(
+        async (alert) => {
+            seen.push(alert);
+        },
+        { name: 'capture', minSeverity, maxSeverity },
+    );
+    return seen;
+};
+
+describe('AlarmClient severity routing', () => {
+    beforeEach(() => {
+        vi.spyOn(console, 'error').mockImplementation(() => {});
+        vi.spyOn(console, 'warn').mockImplementation(() => {});
+        vi.spyOn(console, 'log').mockImplementation(() => {});
+        pdEvent.mockClear();
+    });
+
+    it('defaults to critical when the call site says nothing', () => {
+        const client = makeClient();
+        const seen = capture(client);
+
+        client.create('boom', 'everything is on fire');
+
+        expect(seen).toHaveLength(1);
+        expect(seen[0].severity).toBe('critical');
+    });
+
+    it('honours a configured default severity', () => {
+        const client = makeClient({ defaultSeverity: 'info' });
+        const seen = capture(client);
+
+        client.create('boom', 'everything is on fire');
+
+        expect(seen[0].severity).toBe('info');
+    });
+
+    it('skips handlers whose floor the alarm does not reach', () => {
+        const client = makeClient();
+        const paging = capture(client, 'warning');
+        const chat = capture(client, 'info');
+
+        client.create('rate-limit', 'a user hit a limit', {}, 'info');
+
+        expect(paging).toHaveLength(0);
+        expect(chat).toHaveLength(1);
+    });
+
+    it('skips handlers whose ceiling the alarm exceeds', () => {
+        const client = makeClient();
+        const chat = capture(client, 'info', 'info');
+
+        client.create('rate-limit', 'a user hit a limit', {}, 'info');
+        client.create('outage', 'everything is on fire', {}, 'critical');
+
+        expect(chat.map((alert) => alert.id)).toEqual(['rate-limit']);
+    });
+
+    it('retiers an alarm from config', () => {
+        const client = makeClient({
+            severityOverrides: { 'noisy:*': 'info' },
+        });
+        const paging = capture(client, 'warning');
+        const chat = capture(client, 'info');
+
+        client.create('noisy:thing', 'used to page', {}, 'critical');
+
+        expect(paging).toHaveLength(0);
+        expect(chat[0].severity).toBe('info');
+    });
+
+    it('mutes an alarm from config', () => {
+        const client = makeClient({
+            severityOverrides: { 'noisy:thing': 'mute' },
+        });
+        const chat = capture(client, 'info');
+
+        client.create('noisy:thing', 'not worth reporting');
+        client.create('noisy:thing', 'still not worth reporting');
+
+        expect(chat).toHaveLength(0);
+    });
+
+    it('lets config override a known-error rule', () => {
+        const client = makeClient({
+            severityOverrides: { 'known:thing': 'critical' },
+        });
+        client.setKnownErrors([
+            {
+                match: { id: 'known:thing' },
+                action: { type: 'severity', value: 'info' },
+            },
+        ]);
+        const paging = capture(client, 'warning');
+
+        client.create('known:thing', 'known but escalated');
+
+        expect(paging[0].severity).toBe('critical');
+    });
+
+    it('still respects a no-alert known-error rule', () => {
+        const client = makeClient();
+        client.setKnownErrors([
+            { match: { id: 'known:quiet' }, action: { type: 'no-alert' } },
+        ]);
+        const chat = capture(client, 'info');
+
+        client.create('known:quiet', 'suppressed');
+
+        expect(chat).toHaveLength(0);
+    });
+});
+
+describe('AlarmClient alert payload', () => {
+    beforeEach(() => {
+        vi.spyOn(console, 'error').mockImplementation(() => {});
+        vi.spyOn(console, 'warn').mockImplementation(() => {});
+    });
+
+    it('reports occurrence counts across repeats', () => {
+        const client = makeClient();
+        const seen = capture(client);
+
+        client.create('flap', 'first');
+        client.create('flap', 'second');
+
+        expect(seen[0]).toMatchObject({ repeatCount: 1, isRepeat: false });
+        expect(seen[1]).toMatchObject({ repeatCount: 2, isRepeat: true });
+    });
+
+    it('renders fields as strings and lifts the stack out of the error', () => {
+        const client = makeClient();
+        const seen = capture(client);
+        const error = new Error('kaboom');
+
+        client.create('boom', 'failed', { error, status: 500 }, 'critical');
+
+        expect(seen[0].fields.status).toBe('500');
+        expect(seen[0].trace).toBe(error.stack);
+        expect(seen[0].shortId).toMatch(/^[a-z]+-[a-z]+-[a-z]+$/);
+    });
+
+    it('keeps one failing handler from starving the others', async () => {
+        const client = makeClient();
+        client.addAlertHandler(
+            async () => {
+                throw new Error('transport down');
+            },
+            { name: 'broken' },
+        );
+        const seen = capture(client);
+
+        client.create('boom', 'failed');
+        await Promise.resolve();
+
+        expect(seen).toHaveLength(1);
+    });
+
+    it('suppresses alarms once draining', () => {
+        const client = makeClient();
+        const seen = capture(client);
+
+        client.onServerPrepareShutdown();
+        client.create('boom', 'too late');
+
+        expect(seen).toHaveLength(0);
+    });
+});
+
+describe('AlarmClient transport registration', () => {
+    beforeEach(() => {
+        vi.spyOn(console, 'error').mockImplementation(() => {});
+        vi.spyOn(console, 'warn').mockImplementation(() => {});
+        vi.spyOn(console, 'log').mockImplementation(() => {});
+        pdEvent.mockClear();
+    });
+
+    it('splits info to Slack and everything above it to PagerDuty', async () => {
+        const fetchMock = vi.fn(async () => ({ ok: true, status: 200 }));
+        vi.stubGlobal('fetch', fetchMock);
+
+        const client = makeClient({
+            pagerduty: { enabled: true, routingKey: 'rk' },
+            slack: { enabled: true, webhookUrl: 'https://hooks.example/abc' },
+        });
+        await client.onServerStart();
+
+        client.create('quiet:thing', 'informational', {}, 'info');
+        await vi.waitFor(() => expect(fetchMock).toHaveBeenCalledTimes(1));
+        expect(pdEvent).not.toHaveBeenCalled();
+
+        client.create('loud:thing', 'paging', {}, 'critical');
+        await vi.waitFor(() => expect(pdEvent).toHaveBeenCalledTimes(1));
+        // The pager has it; chat doesn't repeat it.
+        expect(fetchMock).toHaveBeenCalledTimes(1);
+
+        vi.unstubAllGlobals();
+    });
+
+    it('sends every severity to Slack when there is no pager', async () => {
+        const fetchMock = vi.fn(async () => ({ ok: true, status: 200 }));
+        vi.stubGlobal('fetch', fetchMock);
+
+        const client = makeClient({
+            slack: { enabled: true, webhookUrl: 'https://hooks.example/abc' },
+        });
+        await client.onServerStart();
+
+        client.create(
+            'loud:thing',
+            'nowhere else to send this',
+            {},
+            'critical',
+        );
+        await vi.waitFor(() => expect(fetchMock).toHaveBeenCalledTimes(1));
+
+        vi.unstubAllGlobals();
+    });
+
+    it('lets config widen the Slack ceiling back out', async () => {
+        const fetchMock = vi.fn(async () => ({ ok: true, status: 200 }));
+        vi.stubGlobal('fetch', fetchMock);
+
+        const client = makeClient({
+            pagerduty: { enabled: true, routingKey: 'rk' },
+            slack: {
+                enabled: true,
+                webhookUrl: 'https://hooks.example/abc',
+                maxSeverity: 'critical',
+            },
+        });
+        await client.onServerStart();
+
+        client.create('loud:thing', 'paging', {}, 'critical');
+        await vi.waitFor(() => expect(fetchMock).toHaveBeenCalledTimes(1));
+
+        vi.unstubAllGlobals();
+    });
+
+    it('gives each occurrence its own PagerDuty incident by default', async () => {
+        const client = makeClient({
+            pagerduty: { enabled: true, routingKey: 'rk' },
+        });
+        await client.onServerStart();
+
+        client.create('scan:failed', 'first', {}, 'warning');
+        client.create('scan:failed', 'second', {}, 'warning');
+        await vi.waitFor(() => expect(pdEvent).toHaveBeenCalledTimes(2));
+
+        const keys = pdEvent.mock.calls.map(
+            ([arg]: [{ data: { dedup_key: string } }]) => arg.data.dedup_key,
+        );
+        expect(keys[0]).not.toBe(keys[1]);
+    });
+
+    it('collapses repeats of a dedup alarm onto one incident', async () => {
+        const client = makeClient({
+            pagerduty: { enabled: true, routingKey: 'rk' },
+        });
+        await client.onServerStart();
+
+        const raise = () =>
+            client.create(
+                'http_500:POST:/notif/mark-ack:deadlock',
+                'HTTP 500 on POST /notif/mark-ack: deadlock',
+                {},
+                'critical',
+                { dedup: true },
+            );
+        raise();
+        raise();
+        await vi.waitFor(() => expect(pdEvent).toHaveBeenCalledTimes(2));
+
+        const keys = pdEvent.mock.calls.map(
+            ([arg]: [{ data: { dedup_key: string } }]) => arg.data.dedup_key,
+        );
+        expect(keys[0]).toBe('http_500:POST:/notif/mark-ack:deadlock');
+        expect(keys[1]).toBe(keys[0]);
+    });
+
+    it('skips transports that are enabled but not configured', async () => {
+        const client = makeClient({
+            pagerduty: { enabled: true },
+            slack: { enabled: true },
+        });
+        await client.onServerStart();
+
+        const seen = capture(client);
+        client.create('boom', 'nowhere to send this');
+
+        // Only the capturing handler is registered.
+        expect(seen).toHaveLength(1);
+        expect(pdEvent).not.toHaveBeenCalled();
+    });
+});
+
+describe('AlarmClient alarm registry', () => {
+    beforeEach(() => {
+        vi.spyOn(console, 'error').mockImplementation(() => {});
+        vi.spyOn(console, 'warn').mockImplementation(() => {});
+        vi.spyOn(console, 'log').mockImplementation(() => {});
+    });
+
+    it('finds an alarm by its full id or its short id', () => {
+        const client = makeClient();
+        client.create('disk-pressure', 'nearly full');
+
+        const alarm = client.get('disk-pressure');
+        expect(alarm?.message).toBe('nearly full');
+        expect(client.get(alarm!.shortId)).toBe(alarm);
+    });
+
+    it('returns nothing for an id it has never seen', () => {
+        expect(makeClient().get('never-raised')).toBeUndefined();
+    });
+
+    it('forgets an alarm once cleared, under both ids', () => {
+        const client = makeClient();
+        client.create('disk-pressure', 'nearly full');
+        const shortId = client.get('disk-pressure')!.shortId;
+
+        client.clear('disk-pressure');
+
+        expect(client.get('disk-pressure')).toBeUndefined();
+        expect(client.get(shortId)).toBeUndefined();
+    });
+
+    it('ignores a clear for an alarm that is not active', () => {
+        const client = makeClient();
+        expect(() => client.clear('never-raised')).not.toThrow();
+    });
+
+    it('abbreviates long ids in the log line but keeps the short id usable', () => {
+        const log = vi.spyOn(console, 'error').mockImplementation(() => {});
+        const client = makeClient();
+        const longId = 'a-very-long-alarm-identifier-that-wraps';
+
+        client.create(longId, 'noisy');
+
+        const shortId = client.get(longId)!.shortId;
+        expect(log).toHaveBeenCalledWith(
+            `[alarm] ACTIVE ${shortId} (${longId.slice(0, 20)}...) :: noisy`,
+        );
+    });
+
+    it('accumulates fields across repeats of the same alarm', () => {
+        const client = makeClient();
+        const seen = capture(client);
+
+        client.create('flap', 'first', { a: 1 });
+        client.create('flap', 'second', { b: 2 });
+
+        expect(seen[1].fields).toEqual({ a: '1', b: '2' });
+        expect(client.get('flap')?.occurrences).toHaveLength(2);
+    });
+
+    it('names anonymous handlers by their registration order', () => {
+        const client = makeClient();
+        client.addAlertHandler(async () => {
+            throw new Error('down');
+        });
+        expect(() => client.create('boom', 'x')).not.toThrow();
+    });
+
+    it('only logs the drain notice once', () => {
+        const log = vi.spyOn(console, 'log').mockImplementation(() => {});
+        log.mockClear();
+        const client = makeClient();
+
+        client.onServerPrepareShutdown();
+        // A second prepare must not restart the drain.
+        client.onServerPrepareShutdown();
+        client.create('a', 'x');
+        client.create('b', 'y');
+
+        const drainLogs = log.mock.calls.filter(
+            ([message]) =>
+                message === '[alarm] suppressing alarm while draining',
+        );
+        expect(drainLogs).toHaveLength(1);
+    });
+
+    it('substitutes placeholders for an empty id and message', () => {
+        const client = makeClient();
+        const seen = capture(client);
+
+        client.create('', '');
+
+        expect(seen[0]).toMatchObject({
+            id: 'something-bad',
+            message: 'something bad happened',
+        });
+    });
+});
+
+describe('AlarmClient known-error rules', () => {
+    beforeEach(() => {
+        vi.spyOn(console, 'error').mockImplementation(() => {});
+        vi.spyOn(console, 'warn').mockImplementation(() => {});
+        vi.spyOn(console, 'log').mockImplementation(() => {});
+    });
+
+    it('suppresses alerts for a matching rule', () => {
+        const client = makeClient();
+        const seen = capture(client);
+        client.setKnownErrors([
+            { match: { id: 'noisy' }, action: { type: 'no-alert' } },
+        ]);
+
+        client.create('noisy', 'ignore me');
+        client.create('noisy', 'ignore me again');
+
+        expect(seen).toHaveLength(0);
+    });
+
+    it('leaves alarms with a different id alone', () => {
+        const client = makeClient();
+        const seen = capture(client);
+        client.setKnownErrors([
+            { match: { id: 'noisy' }, action: { type: 'no-alert' } },
+        ]);
+
+        client.create('real', 'page me');
+
+        expect(seen).toHaveLength(1);
+    });
+
+    it('only matches when the message matches too', () => {
+        const rules = [
+            {
+                match: { id: 'timeout', message: 'upstream timed out' },
+                action: { type: 'no-alert' as const },
+            },
+        ];
+
+        // Separate clients: suppression is recorded on the alarm, so a
+        // second occurrence of the same id would inherit it.
+        const matching = makeClient();
+        const matchingSeen = capture(matching);
+        matching.setKnownErrors(rules);
+        matching.create('timeout', 'upstream timed out');
+        expect(matchingSeen).toHaveLength(0);
+
+        const differing = makeClient();
+        const differingSeen = capture(differing);
+        differing.setKnownErrors(rules);
+        differing.create('timeout', 'something else entirely');
+        expect(differingSeen.map((alert) => alert.message)).toEqual([
+            'something else entirely',
+        ]);
+    });
+
+    it('only matches when every named field matches', () => {
+        const client = makeClient();
+        const seen = capture(client);
+        client.setKnownErrors([
+            {
+                match: { id: 'http', fields: { status: 404 } },
+                action: { type: 'no-alert' },
+            },
+        ]);
+
+        client.create('http', 'not found', { status: 404 });
+        client.create('http-2', 'server error', { status: 500 });
+
+        expect(seen.map((alert) => alert.id)).toEqual(['http-2']);
+    });
+
+    it('retiers a matching alarm to a lower severity', () => {
+        const client = makeClient();
+        const paging = capture(client, 'error');
+        const chat = capture(client, 'info');
+        client.setKnownErrors([
+            {
+                match: { id: 'flaky' },
+                action: { type: 'severity', value: 'info' },
+            },
+        ]);
+
+        client.create('flaky', 'transient', {}, 'critical');
+
+        expect(paging).toHaveLength(0);
+        expect(chat).toHaveLength(1);
+        expect(chat[0].severity).toBe('info');
+    });
+});

src/backend/clients/alarm/AlarmClient.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -20,64 +20,56 @@
 import { event as pdEvent } from '@pagerduty/pdjs';
 import { inspect } from 'node:util';
 import { createHash } from 'node:crypto';
-import type { IConfig } from '../../types';
+import type { IConfig, PagerSeverity, SeverityRule } from '../../types';
 import { PuterClient } from '../types';
+import {
+    meetsMinSeverity,
+    resolveSeverityOverride,
+    withinMaxSeverity,
+} from './severity';
+import { createSlackAlertHandler } from './slack';
+import type {
+    Alarm,
+    AlarmFields,
+    AlarmOptions,
+    AlertHandler,
+    AlertPayload,
+    KnownErrorRule,
+} from './types';
+
+export type {
+    Alarm,
+    AlarmFields,
+    AlarmOptions,
+    AlertHandler,
+    AlertPayload,
+    KnownErrorRule,
+} from './types';
+export type { PagerSeverity } from '../../types';
 
 // -- Types ------------------------------------------------------------
 
-export interface AlarmFields {
-    error?: Error;
-    [key: string]: unknown;
+interface RegisteredHandler {
+    name: string;
+    /** Lowest severity this transport accepts. */
+    minSeverity: PagerSeverity;
+    /** Highest severity this transport accepts. */
+    maxSeverity: PagerSeverity;
+    handler: AlertHandler;
 }
 
-interface AlarmOccurrence {
-    message: string;
-    fields: AlarmFields;
-    timestamp: number;
-}
-
-interface Alarm {
-    id: string;
-    shortId: string;
-    message: string;
-    fields: AlarmFields;
-    error?: Error;
-    started: number;
-    timestamps: number[];
-    occurrences: AlarmOccurrence[];
-    severity?: PagerSeverity;
-    noAlert?: boolean;
-}
-
-export type PagerSeverity = 'critical' | 'error' | 'warning' | 'info';
-
-export interface AlertPayload {
-    id: string;
-    message: string;
-    source: string;
-    severity: PagerSeverity;
-    custom?: Record<string, unknown>;
-}
-
-type AlertHandler = (alert: AlertPayload) => Promise<void>;
-
-interface KnownErrorRule {
-    match: {
-        id: string;
-        message?: string;
-        fields?: Record<string, unknown>;
-    };
-    action: {
-        type: 'no-alert' | 'severity';
-        value?: PagerSeverity;
-    };
-}
+/** Severity used when neither the call site nor config picks one. */
+const FALLBACK_SEVERITY: PagerSeverity = 'critical';
+/** Keeps `info` alarms out of the paging system unless config says otherwise. */
+const DEFAULT_PAGERDUTY_MIN_SEVERITY: PagerSeverity = 'warning';
+/** Slack's ceiling once a pager exists: chat gets what doesn't page. */
+const DEFAULT_SLACK_MAX_SEVERITY_WITH_PAGER: PagerSeverity = 'info';
 
 // -- Helpers ----------------------------------------------------------
 
 /**
- * Deterministic short identifier derived from an alarm ID.
- * Produces a readable 3-word slug like "amber-delta-fox".
+ * Deterministic short identifier derived from an alarm ID. Produces a readable
+ * 3-word slug like "amber-delta-fox".
  */
 const WORD_POOL = [
     'alpha',
@@ -169,13 +161,17 @@ function cleanFields(fields: AlarmFields): Record<string, string> {
 // -- AlarmClient ------------------------------------------------------
 
 /**
- * Manages system alarms and dispatches alerts to external paging
- * services (PagerDuty, or any registered handler).
+ * Manages system alarms and routes them to alert transports by severity.
+ *
+ * Severity is the routing decision: each transport declares the severity window
+ * it accepts, so `critical` pages on-call while `info` only reaches the chat
+ * channel. Config can retier or mute any alarm id after the fact — see
+ * `pager.severityOverrides` in {@link IConfig}.
  */
 export class AlarmClient extends PuterClient {
     private alarms = new Map<string, Alarm>();
     private aliases = new Map<string, Alarm>();
-    private alertHandlers: AlertHandler[] = [];
+    private alertHandlers: RegisteredHandler[] = [];
     private knownErrors: KnownErrorRule[] = [];
     private draining = false;
     private drainLogged = false;
@@ -187,39 +183,8 @@ export class AlarmClient extends PuterClient {
     // -- Lifecycle ----------------------------------------------------
 
     override async onServerStart(): Promise<void> {
-        const pagerConf = this.config.pager;
-        if (!pagerConf?.pagerduty?.enabled) return;
-
-        const routingKey = pagerConf.pagerduty.routingKey;
-        if (!routingKey) {
-            console.warn(
-                '[alarm] PagerDuty enabled but no routingKey configured',
-            );
-            return;
-        }
-
-        const serverId = this.config.serverId;
-
-        this.alertHandlers.push(async (alert) => {
-            await pdEvent({
-                data: {
-                    routing_key: routingKey,
-                    event_action: 'trigger',
-                    dedup_key: alert.id,
-                    payload: {
-                        summary: alert.message,
-                        source: alert.source,
-                        severity: alert.severity,
-                        custom_details: {
-                            ...alert.custom,
-                            server_id: serverId,
-                        },
-                    },
-                },
-            });
-        });
-
-        console.log('[alarm] PagerDuty handler registered');
+        const paging = this.registerPagerDuty();
+        this.registerSlack({ paging });
     }
 
     override onServerPrepareShutdown(): void {
@@ -228,22 +193,107 @@ export class AlarmClient extends PuterClient {
         console.log('[alarm] entering drain mode — suppressing new alarms');
     }
 
+    /** @returns Whether a working PagerDuty transport was registered. */
+    private registerPagerDuty(): boolean {
+        const pagerDutyConf = this.config.pager?.pagerduty;
+        if (!pagerDutyConf?.enabled) return false;
+
+        const routingKey = pagerDutyConf.routingKey;
+        if (!routingKey) {
+            console.warn(
+                '[alarm] PagerDuty enabled but no routingKey configured',
+            );
+            return false;
+        }
+
+        const serverId = this.config.serverId;
+        const minSeverity =
+            pagerDutyConf.minSeverity ?? DEFAULT_PAGERDUTY_MIN_SEVERITY;
+
+        this.addAlertHandler(
+            async (alert) => {
+                await pdEvent({
+                    data: {
+                        routing_key: routingKey,
+                        event_action: 'trigger',
+                        dedup_key: alert.dedupKey,
+                        payload: {
+                            summary: alert.message,
+                            source: alert.source,
+                            severity: alert.severity,
+                            custom_details: {
+                                ...alert.custom,
+                                server_id: serverId,
+                            },
+                        },
+                    },
+                });
+            },
+            { name: 'pagerduty', minSeverity },
+        );
+
+        console.log(
+            `[alarm] PagerDuty handler registered (min severity: ${minSeverity})`,
+        );
+        return true;
+    }
+
+    private registerSlack({ paging }: { paging: boolean }): void {
+        const slackConf = this.config.pager?.slack;
+        if (!slackConf?.enabled) return;
+
+        if (!slackConf.webhookUrl) {
+            console.warn('[alarm] Slack enabled but no webhookUrl configured');
+            return;
+        }
+
+        const minSeverity = slackConf.minSeverity ?? 'info';
+        // With a pager taking everything from `warning` up, chat is where the
+        // rest is recorded — reposting the paging tiers there only trains
+        // people to skim the channel. Without one, Slack is the only place an
+        // alarm can land, so it takes all of them.
+        const maxSeverity =
+            slackConf.maxSeverity ??
+            (paging ? DEFAULT_SLACK_MAX_SEVERITY_WITH_PAGER : 'critical');
+
+        this.addAlertHandler(
+            createSlackAlertHandler(slackConf, {
+                serverId: this.config.serverId,
+            }),
+            { name: 'slack', minSeverity, maxSeverity },
+        );
+
+        console.log(
+            `[alarm] Slack handler registered (severity ${minSeverity}..${maxSeverity})`,
+        );
+    }
+
     // -- Public API ---------------------------------------------------
 
     /**
-     * Create or update an alarm. If the alarm ID already exists, the
-     * occurrence count is incremented and a repeat alert is dispatched.
+     * Create or update an alarm. If the alarm ID already exists, the occurrence
+     * count is incremented and a repeat alert is dispatched.
      *
-     * `severity` is the PagerDuty severity for this alarm; omit for the
-     * default 'critical'. Use 'info' / 'warning' for expected-but-worth-
-     * tracking signals (e.g. a user hitting a rate limit) so they record
-     * and de-dupe like any other alarm but don't page on-call.
+     * `severity` decides where the alarm lands:
+     *
+     * Critical — a real outage; pages on-call. Reserve it for unhandled server
+     * errors. error — pages on-call as well; prefer `critical` or `warning`.
+     * warning — worth a look soon, but nobody gets woken up. info — a record in
+     * the chat channel; never pages.
+     *
+     * Omit it to take `pager.defaultSeverity` (itself defaulting to
+     * 'critical'). Operators can retier or mute any alarm id from config
+     * afterwards, so the value here is the starting point, not the last word.
+     *
+     * Pass `{ dedup: true }` when repeats of this id are one recurring fault
+     * that should collapse into a single incident — see {@link AlarmOptions}.
      */
     create(
         id: string,
         message: string,
         fields: AlarmFields = {},
         severity?: PagerSeverity,
+        opts: AlarmOptions = {},
     ): void {
         if (this.draining) {
             if (!this.drainLogged) {
@@ -267,8 +317,11 @@ export class AlarmClient extends PuterClient {
             message,
             fields,
             severity,
+            dedup: opts.dedup,
             started: Date.now(),
-            timestamps: [Date.now()],
+            // `recordOccurrence` below stamps the first occurrence; seeding one
+            // here too would report every alarm as one occurrence ahead.
+            timestamps: [],
             occurrences: [],
         };
         if (fields.error) alarm.error = fields.error;
@@ -295,16 +348,28 @@ export class AlarmClient extends PuterClient {
     }
 
     /**
-     * Register an additional alert handler. Handlers are called for
-     * every alarm that isn't suppressed by a known-error rule.
+     * Register an additional alert handler. Handlers are called for every alarm
+     * that isn't suppressed by a known-error rule or muted by config, and whose
+     * severity falls inside the handler's own `minSeverity`..`maxSeverity`
+     * window (default: everything).
      */
-    addAlertHandler(handler: AlertHandler): void {
-        this.alertHandlers.push(handler);
+    addAlertHandler(
+        handler: AlertHandler,
+        opts: {
+            name?: string;
+            minSeverity?: PagerSeverity;
+            maxSeverity?: PagerSeverity;
+        } = {},
+    ): void {
+        this.alertHandlers.push({
+            name: opts.name ?? `handler-${this.alertHandlers.length}`,
+            minSeverity: opts.minSeverity ?? 'info',
+            maxSeverity: opts.maxSeverity ?? 'critical',
+            handler,
+        });
     }
 
-    /**
-     * Add rules that can suppress or adjust severity of known errors.
-     */
+    /** Add rules that can suppress or adjust severity of known errors. */
     setKnownErrors(rules: KnownErrorRule[]): void {
         this.knownErrors = rules;
     }
@@ -381,25 +446,72 @@ export class AlarmClient extends PuterClient {
         this.dispatchAlert(alarm);
     }
 
+    /**
+     * Call-site severity, then any known-error rule (both already on the
+     * alarm), then the config override — so an operator always has the last
+     * word over what the code asked for.
+     */
+    private resolveSeverity(alarm: Alarm): SeverityRule {
+        const base =
+            alarm.severity ??
+            this.config.pager?.defaultSeverity ??
+            FALLBACK_SEVERITY;
+        return (
+            resolveSeverityOverride(
+                alarm.id,
+                this.config.pager?.severityOverrides,
+            ) ?? base
+        );
+    }
+
     private dispatchAlert(alarm: Alarm): void {
-        const severity = alarm.severity ?? 'critical';
+        const resolved = this.resolveSeverity(alarm);
+        if (resolved === 'mute') {
+            if (!alarm.muteLogged) {
+                alarm.muteLogged = true;
+                console.log(`[alarm] MUTED by config ${displayId(alarm)}`);
+            }
+            return;
+        }
+        alarm.severity = resolved;
+
         const fieldsClean = cleanFields(alarm.fields);
+        const repeatCount = alarm.timestamps.length;
+
+        const id = alarm.id || 'something-bad';
 
         const payload: AlertPayload = {
-            id: alarm.id || 'something-bad',
+            id,
+            // A de-duplicating transport should fold repeats of a recurring
+            // fault into one incident, but everything else is a fresh event
+            // each time it fires — the start time keeps occurrence numbering
+            // from colliding with an incident left open by an earlier boot.
+            dedupKey: alarm.dedup
+                ? id
+                : `${id}#${alarm.started}.${repeatCount}`,
+            shortId: alarm.shortId,
             message: alarm.message || alarm.id || 'something bad happened',
             source: 'alarm',
-            severity,
+            severity: resolved,
+            fields: fieldsClean,
+            trace: alarm.error?.stack,
+            repeatCount,
+            isRepeat: repeatCount > 1,
             custom: {
                 fields: fieldsClean,
                 trace: alarm.error?.stack,
-                repeat_count: alarm.timestamps.length,
+                repeat_count: repeatCount,
             },
         };
 
-        for (const handler of this.alertHandlers) {
+        for (const { name, minSeverity, maxSeverity, handler } of this
+            .alertHandlers) {
+            if (!meetsMinSeverity(resolved, minSeverity)) continue;
+            if (!withinMaxSeverity(resolved, maxSeverity)) continue;
             handler(payload).catch((err) => {
-                console.error(`[alarm] alert handler failed: ${err?.message}`);
+                console.error(
+                    `[alarm] ${name} alert handler failed: ${err?.message}`,
+                );
             });
         }
     }

src/backend/clients/alarm/severity.test.ts

@@ -0,0 +1,76 @@
+import { describe, expect, it, vi } from 'vitest';
+import { meetsMinSeverity, resolveSeverityOverride } from './severity';
+
+describe('meetsMinSeverity', () => {
+    it('accepts everything at or above the floor', () => {
+        expect(meetsMinSeverity('critical', 'warning')).toBe(true);
+        expect(meetsMinSeverity('error', 'warning')).toBe(true);
+        expect(meetsMinSeverity('warning', 'warning')).toBe(true);
+        expect(meetsMinSeverity('info', 'warning')).toBe(false);
+    });
+
+    it('lets an info floor take every severity', () => {
+        for (const severity of [
+            'critical',
+            'error',
+            'warning',
+            'info',
+        ] as const) {
+            expect(meetsMinSeverity(severity, 'info')).toBe(true);
+        }
+    });
+});
+
+describe('resolveSeverityOverride', () => {
+    it('returns undefined without overrides or on no match', () => {
+        expect(resolveSeverityOverride('a:b', undefined)).toBeUndefined();
+        expect(
+            resolveSeverityOverride('a:b', { 'c:*': 'info' }),
+        ).toBeUndefined();
+    });
+
+    it('matches an exact id', () => {
+        expect(
+            resolveSeverityOverride('cronMonitor:lowSignupRate', {
+                'cronMonitor:lowSignupRate': 'info',
+            }),
+        ).toBe('info');
+    });
+
+    it('matches a prefix pattern', () => {
+        expect(
+            resolveSeverityOverride('cronMonitor:high_aiLogEntries', {
+                'cronMonitor:*': 'warning',
+            }),
+        ).toBe('warning');
+    });
+
+    it('prefers the exact id over a prefix pattern', () => {
+        expect(
+            resolveSeverityOverride('cronMonitor:lowSignupRate', {
+                'cronMonitor:*': 'warning',
+                'cronMonitor:lowSignupRate': 'mute',
+            }),
+        ).toBe('mute');
+    });
+
+    it('prefers the longest matching prefix', () => {
+        expect(
+            resolveSeverityOverride('abuse:card-verification:setup-failed', {
+                'abuse:*': 'info',
+                'abuse:card-verification:*': 'mute',
+            }),
+        ).toBe('mute');
+    });
+
+    it('drops an unrecognized rule rather than guessing', () => {
+        const warn = vi.spyOn(console, 'warn').mockImplementation(() => {});
+        expect(
+            resolveSeverityOverride('a:b', {
+                'a:b': 'silent' as unknown as 'mute',
+            }),
+        ).toBeUndefined();
+        expect(warn).toHaveBeenCalled();
+        warn.mockRestore();
+    });
+});

src/backend/clients/alarm/severity.ts

@@ -0,0 +1,94 @@
+/*
+ * Copyright (C) 2024-present Puter Technologies Inc.
+ *
+ * This file is part of Puter.
+ *
+ * Puter is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+import type { PagerSeverity, SeverityRule } from '../../types';
+
+/** Ascending urgency. A transport takes everything at or above its floor. */
+const RANK: Record<PagerSeverity, number> = {
+    info: 0,
+    warning: 1,
+    error: 2,
+    critical: 3,
+};
+
+const SEVERITIES = Object.keys(RANK) as PagerSeverity[];
+
+export function isPagerSeverity(value: unknown): value is PagerSeverity {
+    return typeof value === 'string' && value in RANK;
+}
+
+/** True when `severity` is urgent enough for a transport whose floor is `min`. */
+export function meetsMinSeverity(
+    severity: PagerSeverity,
+    min: PagerSeverity,
+): boolean {
+    return RANK[severity] >= RANK[min];
+}
+
+/**
+ * True when `severity` is quiet enough for a transport whose ceiling is `max`.
+ * A ceiling is what keeps a chat transport from repeating everything the pager
+ * already delivered.
+ */
+export function withinMaxSeverity(
+    severity: PagerSeverity,
+    max: PagerSeverity,
+): boolean {
+    return RANK[severity] <= RANK[max];
+}
+
+/**
+ * Look up the operator override for an alarm id. Exact ids win over prefix
+ * patterns (`cronMonitor:*`); among patterns the longest prefix wins, so a
+ * specific rule can carve an exception out of a broad one.
+ */
+export function resolveSeverityOverride(
+    id: string,
+    overrides: Record<string, SeverityRule> | undefined,
+): SeverityRule | undefined {
+    if (!overrides) return undefined;
+
+    const exact = overrides[id];
+    if (exact !== undefined) return validRule(id, exact);
+
+    let bestLength = -1;
+    let best: SeverityRule | undefined;
+    for (const [pattern, rule] of Object.entries(overrides)) {
+        if (!pattern.endsWith('*')) continue;
+        const prefix = pattern.slice(0, -1);
+        if (!id.startsWith(prefix)) continue;
+        if (prefix.length <= bestLength) continue;
+        bestLength = prefix.length;
+        best = rule;
+    }
+    return best === undefined ? undefined : validRule(id, best);
+}
+
+/**
+ * A typo in the override map would otherwise silently mute or escalate an
+ * alarm, so an unrecognized value is dropped with a warning instead.
+ */
+function validRule(id: string, rule: SeverityRule): SeverityRule | undefined {
+    if (rule === 'mute' || isPagerSeverity(rule)) return rule;
+    console.warn(
+        `[alarm] ignoring invalid severity override "${rule}" for ${id} ` +
+            `(expected mute or one of ${SEVERITIES.join(', ')})`,
+    );
+    return undefined;
+}

src/backend/clients/alarm/slack.test.ts

@@ -0,0 +1,206 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
+import { buildSlackMessage, createSlackAlertHandler } from './slack';
+import type { AlertPayload } from './types';
+
+const alert = (over: Partial<AlertPayload> = {}): AlertPayload => ({
+    id: 'cronMonitor:high_aiLogEntries',
+    dedupKey: 'cronMonitor:high_aiLogEntries#1.1',
+    shortId: 'amber-delta-fox',
+    message: 'High AI log entries: 1200 in the last 10 minutes',
+    source: 'alarm',
+    severity: 'warning',
+    fields: { count: '1200', threshold: '1000' },
+    repeatCount: 1,
+    isRepeat: false,
+    ...over,
+});
+
+describe('buildSlackMessage', () => {
+    it('renders severity, message and fields', () => {
+        const msg = buildSlackMessage(alert(), {
+            channel: '#alerts',
+            username: 'puter-alarms',
+            serverId: 'oregon',
+        });
+
+        expect(msg.text).toContain('[WARNING]');
+        expect(msg.text).toContain('High AI log entries');
+        expect(msg.channel).toBe('#alerts');
+        expect(msg.username).toBe('puter-alarms');
+        expect(msg.attachments[0].fields).toEqual([
+            { title: 'count', value: '1200', short: true },
+            { title: 'threshold', value: '1000', short: true },
+        ]);
+        expect(msg.attachments[0].footer).toBe(
+            'amber-delta-fox • cronMonitor:high_aiLogEntries • oregon',
+        );
+    });
+
+    it('marks repeats with an occurrence count', () => {
+        const msg = buildSlackMessage(
+            alert({ repeatCount: 7, isRepeat: true }),
+        );
+        expect(msg.text).toContain('(x7)');
+    });
+
+    it('colours each severity differently', () => {
+        const colors = (['critical', 'error', 'warning', 'info'] as const).map(
+            (severity) =>
+                buildSlackMessage(alert({ severity })).attachments[0].color,
+        );
+        expect(new Set(colors).size).toBe(4);
+    });
+
+    it('puts the stack in a code block and keeps it out of the fields', () => {
+        const msg = buildSlackMessage(
+            alert({
+                fields: { error: 'Error: boom', path: '/api/x' },
+                trace: 'Error: boom\n    at handler',
+            }),
+        );
+        expect(msg.attachments[0].text).toBe(
+            '```Error: boom\n    at handler```',
+        );
+        expect(msg.attachments[0].fields.map((f) => f.title)).toEqual(['path']);
+    });
+
+    it('truncates long values and caps the field count', () => {
+        const fields: Record<string, string> = { long: 'x'.repeat(1000) };
+        for (let i = 0; i < 30; i++) fields[`f${i}`] = String(i);
+
+        const msg = buildSlackMessage(alert({ fields }));
+        expect(msg.attachments[0].fields.length).toBe(12);
+        expect(msg.attachments[0].fields[0].value).toHaveLength(400);
+        expect(msg.attachments[0].fields[0].value.endsWith('…')).toBe(true);
+    });
+
+    it('omits channel and username when unset', () => {
+        const msg = buildSlackMessage(alert());
+        expect(msg.channel).toBeUndefined();
+        expect(msg.username).toBeUndefined();
+    });
+});
+
+describe('createSlackAlertHandler', () => {
+    let fetchMock: ReturnType<typeof vi.fn>;
+
+    beforeEach(() => {
+        vi.useFakeTimers();
+        fetchMock = vi.fn(async () => ({ ok: true, status: 200 }));
+        vi.stubGlobal('fetch', fetchMock);
+    });
+
+    afterEach(() => {
+        vi.useRealTimers();
+        vi.unstubAllGlobals();
+    });
+
+    it('posts the payload to the webhook', async () => {
+        const handler = createSlackAlertHandler({
+            webhookUrl: 'https://hooks.example/abc',
+            channel: '#alerts',
+        });
+        await handler(alert());
+
+        expect(fetchMock).toHaveBeenCalledTimes(1);
+        const [url, init] = fetchMock.mock.calls[0];
+        expect(url).toBe('https://hooks.example/abc');
+        expect(init.method).toBe('POST');
+        expect(JSON.parse(init.body).channel).toBe('#alerts');
+    });
+
+    it('throttles repeats of the same alarm and lets other ids through', async () => {
+        const handler = createSlackAlertHandler({
+            webhookUrl: 'https://hooks.example/abc',
+            repeatThrottleMs: 60_000,
+        });
+
+        await handler(alert());
+        await handler(alert({ repeatCount: 2, isRepeat: true }));
+        expect(fetchMock).toHaveBeenCalledTimes(1);
+
+        await handler(alert({ id: 'other:alarm' }));
+        expect(fetchMock).toHaveBeenCalledTimes(2);
+
+        vi.advanceTimersByTime(60_000);
+        await handler(alert({ repeatCount: 3, isRepeat: true }));
+        expect(fetchMock).toHaveBeenCalledTimes(3);
+    });
+
+    it('posts every occurrence when throttling is disabled', async () => {
+        const handler = createSlackAlertHandler({
+            webhookUrl: 'https://hooks.example/abc',
+            repeatThrottleMs: 0,
+        });
+
+        await handler(alert());
+        await handler(alert({ repeatCount: 2, isRepeat: true }));
+        expect(fetchMock).toHaveBeenCalledTimes(2);
+    });
+
+    it('does not let a failed post consume the throttle slot', async () => {
+        fetchMock.mockResolvedValueOnce({ ok: false, status: 500 });
+        const handler = createSlackAlertHandler({
+            webhookUrl: 'https://hooks.example/abc',
+            repeatThrottleMs: 60_000,
+        });
+
+        await expect(handler(alert())).rejects.toThrow('500');
+        await handler(alert());
+        expect(fetchMock).toHaveBeenCalledTimes(2);
+    });
+
+    it('releases the throttle slot when the post itself errors', async () => {
+        fetchMock.mockRejectedValueOnce(new Error('socket hang up'));
+        const handler = createSlackAlertHandler({
+            webhookUrl: 'https://hooks.example/abc',
+            repeatThrottleMs: 60_000,
+        });
+
+        await expect(handler(alert())).rejects.toThrow('socket hang up');
+        await handler(alert());
+        expect(fetchMock).toHaveBeenCalledTimes(2);
+    });
+
+    it('evicts throttle entries that have aged out once the map fills', async () => {
+        const throttleMs = 60_000;
+        const handler = createSlackAlertHandler({
+            webhookUrl: 'https://hooks.example/abc',
+            repeatThrottleMs: throttleMs,
+        });
+
+        // Fill to the high-water mark, then age every entry past the window.
+        for (let i = 0; i < 5000; i++) {
+            await handler(alert({ id: `aged:${i}` }));
+        }
+        vi.advanceTimersByTime(throttleMs);
+
+        await handler(alert({ id: 'fresh' }));
+        expect(fetchMock).toHaveBeenCalledTimes(5001);
+
+        // The aged ids were pruned, so they post again immediately.
+        await handler(alert({ id: 'aged:0' }));
+        expect(fetchMock).toHaveBeenCalledTimes(5002);
+    });
+
+    it('drops the oldest entry when the map is full of live ones', async () => {
+        const handler = createSlackAlertHandler({
+            webhookUrl: 'https://hooks.example/abc',
+            repeatThrottleMs: 60_000,
+        });
+
+        for (let i = 0; i < 5000; i++) {
+            await handler(alert({ id: `live:${i}` }));
+        }
+
+        // Nothing has aged out, so the oldest id makes room for the new one.
+        await handler(alert({ id: 'newcomer' }));
+        expect(fetchMock).toHaveBeenCalledTimes(5001);
+
+        await handler(alert({ id: 'live:0' }));
+        expect(fetchMock).toHaveBeenCalledTimes(5002);
+        // The newcomer is still throttled.
+        await handler(alert({ id: 'newcomer' }));
+        expect(fetchMock).toHaveBeenCalledTimes(5002);
+    });
+});

src/backend/clients/alarm/slack.ts

@@ -0,0 +1,178 @@
+/*
+ * Copyright (C) 2024-present Puter Technologies Inc.
+ *
+ * This file is part of Puter.
+ *
+ * Puter is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+import type { ISlackAlertConfig, PagerSeverity } from '../../types';
+import type { AlertHandler, AlertPayload } from './types';
+
+const REQUEST_TIMEOUT_MS = 5000;
+export const DEFAULT_REPEAT_THROTTLE_MS = 15 * 60 * 1000;
+
+/** Beyond this many tracked alarm ids, throttle state is pruned. */
+const MAX_THROTTLE_ENTRIES = 5000;
+
+const MAX_FIELDS = 12;
+const MAX_FIELD_VALUE = 400;
+const MAX_TRACE = 1500;
+/** Values under this length sit two-per-row in the Slack attachment. */
+const SHORT_FIELD_LENGTH = 40;
+
+const STYLE: Record<PagerSeverity, { emoji: string; color: string }> = {
+    critical: { emoji: ':rotating_light:', color: '#d64545' },
+    error: { emoji: ':red_circle:', color: '#e08d4c' },
+    warning: { emoji: ':warning:', color: '#e0b84c' },
+    info: { emoji: ':information_source:', color: '#4c8de0' },
+};
+
+interface SlackField {
+    title: string;
+    value: string;
+    short: boolean;
+}
+
+export interface SlackMessage {
+    text: string;
+    channel?: string;
+    username?: string;
+    icon_emoji?: string;
+    attachments: Array<{
+        color: string;
+        fallback: string;
+        fields: SlackField[];
+        footer: string;
+        mrkdwn_in: string[];
+        text?: string;
+    }>;
+}
+
+function truncate(value: string, max: number): string {
+    return value.length <= max ? value : `${value.slice(0, max - 1)}…`;
+}
+
+/**
+ * Render an alert as an incoming-webhook payload: severity-coloured attachment,
+ * the alarm's fields as a table, and the stack (when there is one) as a code
+ * block. Split out from the handler so the formatting is testable on its own.
+ */
+export function buildSlackMessage(
+    alert: AlertPayload,
+    opts: { channel?: string; username?: string; serverId?: string } = {},
+): SlackMessage {
+    const style = STYLE[alert.severity] ?? STYLE.info;
+    const repeat = alert.isRepeat ? ` (x${alert.repeatCount})` : '';
+    const headline = `${style.emoji} *[${alert.severity.toUpperCase()}]* ${alert.message}${repeat}`;
+
+    const fields: SlackField[] = [];
+    for (const [key, value] of Object.entries(alert.fields)) {
+        if (fields.length >= MAX_FIELDS) break;
+        // `error` is already rendered as the trace block below.
+        if (key === 'error') continue;
+        const rendered = truncate(value, MAX_FIELD_VALUE);
+        fields.push({
+            title: key,
+            value: rendered,
+            short: rendered.length <= SHORT_FIELD_LENGTH,
+        });
+    }
+
+    const footerParts = [alert.shortId, alert.id];
+    if (opts.serverId) footerParts.push(opts.serverId);
+
+    return {
+        text: headline,
+        ...(opts.channel ? { channel: opts.channel } : {}),
+        ...(opts.username ? { username: opts.username } : {}),
+        attachments: [
+            {
+                color: style.color,
+                fallback: `[${alert.severity}] ${alert.message}`,
+                fields,
+                footer: footerParts.join(' • '),
+                mrkdwn_in: ['text'],
+                ...(alert.trace
+                    ? { text: '```' + truncate(alert.trace, MAX_TRACE) + '```' }
+                    : {}),
+            },
+        ],
+    };
+}
+
+/**
+ * Post alerts to a Slack incoming webhook. Repeats of the same alarm id are
+ * throttled so a hot loop doesn't flood the channel — the occurrence count on
+ * the next post that gets through tells the reader what they missed.
+ */
+export function createSlackAlertHandler(
+    conf: ISlackAlertConfig,
+    opts: { serverId?: string } = {},
+): AlertHandler {
+    const webhookUrl = conf.webhookUrl as string;
+    const throttleMs = conf.repeatThrottleMs ?? DEFAULT_REPEAT_THROTTLE_MS;
+    const lastPosted = new Map<string, number>();
+
+    const shouldPost = (alert: AlertPayload): boolean => {
+        if (throttleMs <= 0) return true;
+        const now = Date.now();
+        const previous = lastPosted.get(alert.id);
+        if (previous !== undefined && now - previous < throttleMs) return false;
+
+        if (lastPosted.size >= MAX_THROTTLE_ENTRIES) {
+            for (const [id, at] of lastPosted) {
+                if (now - at >= throttleMs) lastPosted.delete(id);
+            }
+            // Still full of live entries — drop the oldest to stay bounded.
+            if (lastPosted.size >= MAX_THROTTLE_ENTRIES) {
+                const oldest = lastPosted.keys().next().value;
+                if (oldest !== undefined) lastPosted.delete(oldest);
+            }
+        }
+        lastPosted.set(alert.id, now);
+        return true;
+    };
+
+    return async (alert) => {
+        if (!shouldPost(alert)) return;
+
+        const controller = new AbortController();
+        const timer = setTimeout(() => controller.abort(), REQUEST_TIMEOUT_MS);
+        try {
+            const res = await fetch(webhookUrl, {
+                method: 'POST',
+                headers: { 'Content-Type': 'application/json' },
+                body: JSON.stringify(
+                    buildSlackMessage(alert, {
+                        channel: conf.channel,
+                        username: conf.username,
+                        serverId: opts.serverId,
+                    }),
+                ),
+                signal: controller.signal,
+            });
+            if (!res.ok) {
+                // A rejected post shouldn't leave the id marked as delivered.
+                lastPosted.delete(alert.id);
+                throw new Error(`Slack webhook returned ${res.status}`);
+            }
+        } catch (err) {
+            lastPosted.delete(alert.id);
+            throw err;
+        } finally {
+            clearTimeout(timer);
+        }
+    };
+}

src/backend/clients/alarm/types.ts

@@ -0,0 +1,95 @@
+/*
+ * Copyright (C) 2024-present Puter Technologies Inc.
+ *
+ * This file is part of Puter.
+ *
+ * Puter is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+import type { PagerSeverity } from '../../types';
+
+export interface AlarmFields {
+    error?: Error;
+    [key: string]: unknown;
+}
+
+export interface AlarmOccurrence {
+    message: string;
+    fields: AlarmFields;
+    timestamp: number;
+}
+
+export interface AlarmOptions {
+    /**
+     * Collapse repeats of this alarm id into a single incident on transports
+     * that de-duplicate (PagerDuty). Only right when the id already pins down
+     * one recurring fault — an uncaught error on a route, say — so that N
+     * occurrences really are one thing to fix. Off by default: every other
+     * alarm raises its own incident per occurrence.
+     */
+    dedup?: boolean;
+}
+
+export interface Alarm extends AlarmOptions {
+    id: string;
+    shortId: string;
+    message: string;
+    fields: AlarmFields;
+    error?: Error;
+    started: number;
+    timestamps: number[];
+    occurrences: AlarmOccurrence[];
+    severity?: PagerSeverity;
+    noAlert?: boolean;
+    /** Set once a config mute has been logged, so it's reported only once. */
+    muteLogged?: boolean;
+}
+
+export interface AlertPayload {
+    id: string;
+    /**
+     * Key a de-duplicating transport groups by. Equal to `id` for alarms raised
+     * with `dedup`, and unique per occurrence for everything else.
+     */
+    dedupKey: string;
+    /** Readable slug for the same alarm, for humans quoting it back. */
+    shortId: string;
+    message: string;
+    source: string;
+    severity: PagerSeverity;
+    /** Field values rendered as strings, ready to display. */
+    fields: Record<string, string>;
+    /** Stack of the attached error, when the alarm carried one. */
+    trace?: string;
+    /** Total occurrences of this alarm so far, including this one. */
+    repeatCount: number;
+    /** False for the first occurrence of an alarm id. */
+    isRepeat: boolean;
+    /** PagerDuty `custom_details` payload. */
+    custom?: Record<string, unknown>;
+}
+
+export type AlertHandler = (alert: AlertPayload) => Promise<void>;
+
+export interface KnownErrorRule {
+    match: {
+        id: string;
+        message?: string;
+        fields?: Record<string, unknown>;
+    };
+    action: {
+        type: 'no-alert' | 'severity';
+        value?: PagerSeverity;
+    };
+}

src/backend/clients/clickhouse/ClickhouseClient.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.

src/backend/clients/database/DatabaseClient.test.ts

@@ -0,0 +1,247 @@
+/**
+ * Copyright (C) 2024-present Puter Technologies Inc.
+ *
+ * This file is part of Puter.
+ *
+ * Puter is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+import { describe, expect, it } from 'vitest';
+import type { IConfig } from '../../types';
+import { AbstractDatabaseClient, type WriteResult } from './DatabaseClient';
+import { DatabaseClientFactory } from './index.js';
+import { MySQLDatabaseClient } from './MySQLDatabaseClient.js';
+import { PostgresDatabaseClient } from './PostgresDatabaseClient.js';
+import { SqliteDatabaseClient } from './SqliteDatabaseClient.js';
+
+const config = (engine: string): IConfig =>
+    ({ port: 0, extensions: [], database: { engine } }) as IConfig;
+
+const sqlite = () => new SqliteDatabaseClient(config('sqlite'));
+const mysql = () => new MySQLDatabaseClient(config('mysql'));
+const postgres = () => new PostgresDatabaseClient(config('postgres'));
+
+/**
+ * Minimal concrete client backed by fixture rows — exercises the shared helpers
+ * on `AbstractDatabaseClient` that the real engines inherit.
+ */
+class FixtureDatabaseClient extends AbstractDatabaseClient {
+    override readonly engineName = 'fixture';
+    readonly reads: string[] = [];
+    readonly preads: string[] = [];
+    readonly writes: { query: string; params: unknown[] }[] = [];
+
+    constructor(
+        private readonly replicaRows: Record<string, unknown>[] | Error,
+        private readonly primaryRows: Record<string, unknown>[] = [],
+    ) {
+        super(config('fixture'));
+    }
+
+    override async read(query: string): Promise<Record<string, unknown>[]> {
+        this.reads.push(query);
+        if (this.replicaRows instanceof Error) throw this.replicaRows;
+        return this.replicaRows;
+    }
+
+    override async pread(query: string): Promise<Record<string, unknown>[]> {
+        this.preads.push(query);
+        return this.primaryRows;
+    }
+
+    override async write(
+        query: string,
+        params: unknown[] = [],
+    ): Promise<WriteResult> {
+        this.writes.push({ query, params });
+        return { insertId: 1, affectedRows: 1, anyRowsAffected: true };
+    }
+}
+
+describe('DatabaseClientFactory', () => {
+    it('picks sqlite when no engine is configured', () => {
+        expect(
+            new DatabaseClientFactory({ port: 0, extensions: [] } as IConfig),
+        ).toBeInstanceOf(SqliteDatabaseClient);
+    });
+
+    it('refuses an unknown engine name', () => {
+        expect(() => new DatabaseClientFactory(config('cassandra'))).toThrow(
+            'Unknown database engine: cassandra',
+        );
+    });
+});
+
+describe('AbstractDatabaseClient — unimplemented surface', () => {
+    const bare = () => new AbstractDatabaseClient(config('none'));
+
+    it('refuses to run queries until a subclass implements them', async () => {
+        await expect(bare().read('SELECT 1')).rejects.toThrow(
+            'DatabaseClient.read() not implemented',
+        );
+        await expect(bare().pread('SELECT 1')).rejects.toThrow(
+            'DatabaseClient.pread() not implemented',
+        );
+        await expect(bare().write('DELETE FROM x')).rejects.toThrow(
+            'DatabaseClient.write() not implemented',
+        );
+        await expect(bare().batchWrite([])).rejects.toThrow(
+            'DatabaseClient.batchWrite() not implemented',
+        );
+    });
+});
+
+describe('AbstractDatabaseClient — replica-aware reads', () => {
+    it('returns replica rows without waiting on the primary', async () => {
+        const client = new FixtureDatabaseClient([{ id: 1 }], [{ id: 2 }]);
+        await expect(client.tryHardRead('SELECT 1')).resolves.toEqual([
+            { id: 1 },
+        ]);
+    });
+
+    it('falls back to the primary when the replica has not caught up', async () => {
+        const client = new FixtureDatabaseClient([], [{ id: 2 }]);
+        await expect(client.tryHardRead('SELECT 1')).resolves.toEqual([
+            { id: 2 },
+        ]);
+    });
+
+    it('falls back to the primary when the replica read throws', async () => {
+        const client = new FixtureDatabaseClient(
+            new Error('replica unavailable'),
+            [{ id: 3 }],
+        );
+        await expect(client.tryHardRead('SELECT 1')).resolves.toEqual([
+            { id: 3 },
+        ]);
+    });
+
+    it('names the failing query when a required read finds nothing', async () => {
+        const client = new FixtureDatabaseClient([], []);
+        await expect(
+            client.requireRead('SELECT * FROM `user` WHERE `id` = ?'),
+        ).rejects.toThrow(
+            'required read returned no rows: SELECT * FROM `user` WHERE `id` = ?',
+        );
+    });
+});
+
+describe('AbstractDatabaseClient — SQL generation', () => {
+    it('generates an INSERT with quoted columns and placeholders', async () => {
+        const client = new FixtureDatabaseClient([]);
+        await client.insert('user', { username: 'ada', email: null });
+
+        expect(client.writes).toEqual([
+            {
+                query: 'INSERT INTO `user` (`username`, `email`) VALUES (?, ?)',
+                params: ['ada', null],
+            },
+        ]);
+    });
+
+    it('quotes each dotted segment and escapes embedded backticks', () => {
+        const client = sqlite();
+        expect(client.quoteIdentifier('user')).toBe('`user`');
+        expect(client.quoteIdentifier('db.user.id')).toBe('`db`.`user`.`id`');
+        expect(client.quoteIdentifier('user.*')).toBe('`user`.*');
+        expect(client.quoteIdentifier('we`ird')).toBe('`we``ird`');
+    });
+
+    it('quotes postgres identifiers with double quotes', () => {
+        const client = postgres();
+        expect(client.quoteIdentifier('db.user')).toBe('"db"."user"');
+        expect(client.quoteIdentifier('we"ird')).toBe('"we""ird"');
+        expect(client.quoteIdentifier('user.*')).toBe('"user".*');
+    });
+
+    it('renders booleans the way each engine expects', () => {
+        expect(sqlite().booleanLiteral(true)).toBe('1');
+        expect(sqlite().booleanValue(false)).toBe(0);
+        expect(postgres().booleanLiteral(true)).toBe('TRUE');
+        expect(postgres().booleanLiteral(false)).toBe('FALSE');
+        expect(postgres().booleanValue(true)).toBe(true);
+    });
+
+    it('picks the engine-specific ignore-conflict syntax', () => {
+        expect(sqlite().insertIgnoreInto('kv')).toBe(
+            'INSERT OR IGNORE INTO `kv`',
+        );
+        expect(sqlite().insertIgnoreSuffix()).toBe('');
+        expect(postgres().insertIgnoreInto('kv')).toBe('INSERT INTO "kv"');
+        expect(postgres().insertIgnoreSuffix()).toBe(' ON CONFLICT DO NOTHING');
+        expect(mysql().insertIgnoreInto('kv')).toBe('INSERT IGNORE INTO `kv`');
+        expect(mysql().insertIgnoreSuffix()).toBe('');
+    });
+
+    it('builds an upsert clause per engine', () => {
+        expect(mysql().upsertClause(['user_id'], ['value', 'dt'])).toBe(
+            'ON DUPLICATE KEY UPDATE `value` = ?, `dt` = ?',
+        );
+        expect(sqlite().upsertClause(['user_id', 'app'], ['value'])).toBe(
+            'ON CONFLICT(`user_id`, `app`) DO UPDATE SET `value` = ?',
+        );
+        expect(postgres().upsertClause(['user_id'], ['value'])).toBe(
+            'ON CONFLICT("user_id") DO UPDATE SET "value" = ?',
+        );
+    });
+
+    it('rejects an upsert with nothing to update', () => {
+        expect(() => sqlite().upsertClause(['user_id'], [])).toThrow(
+            'upsertClause requires at least one update column',
+        );
+    });
+
+    it('extracts JSON text using each engine dialect', () => {
+        expect(sqlite().jsonTextExtract('`metadata`', ['a', 'b'])).toBe(
+            "json_extract(`metadata`, '$.a.b')",
+        );
+        expect(mysql().jsonTextExtract('`metadata`', ['a'])).toBe(
+            "JSON_UNQUOTE(JSON_EXTRACT(`metadata`, '$.a'))",
+        );
+        expect(postgres().jsonTextExtract('"metadata"', ['a', 'b'])).toBe(
+            `"metadata" #>> ARRAY['a', 'b']`,
+        );
+    });
+
+    it('escapes quotes inside JSON path segments', () => {
+        expect(sqlite().jsonTextExtract('`m`', ["it's"])).toBe(
+            "json_extract(`m`, '$.it''s')",
+        );
+    });
+
+    it('coalesces expressions and rejects an empty list', () => {
+        expect(sqlite().nullCoalesce('`a`', '`b`', '0')).toBe(
+            'COALESCE(`a`, `b`, 0)',
+        );
+        expect(() => sqlite().nullCoalesce()).toThrow(
+            'nullCoalesce requires at least one expression',
+        );
+    });
+
+    it('only postgres needs a RETURNING clause to learn the insert id', () => {
+        expect(postgres().returningIdClause()).toBe(' RETURNING id');
+        expect(sqlite().returningIdClause()).toBe('');
+        expect(mysql().returningIdClause()).toBe('');
+    });
+
+    it('falls back to `otherwise` for an engine with no explicit choice', () => {
+        const client = new FixtureDatabaseClient([]);
+        expect(
+            client.case({ sqlite: 'a', mysql: 'b', otherwise: 'fallback' }),
+        ).toBe('fallback');
+        expect(client.case({ fixture: 'exact', otherwise: 'fallback' })).toBe(
+            'exact',
+        );
+    });
+});

src/backend/clients/database/DatabaseClient.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -37,8 +37,8 @@ type SqlJsonPath = readonly [string, ...string[]];
  * Base database client. Subclasses must override every method that throws here.
  *
  * Do not instantiate directly — use the factory exported from
- * `clients/database/index.ts` which picks the right implementation
- * based on `config.database.engine`.
+ * `clients/database/index.ts` which picks the right implementation based on
+ * `config.database.engine`.
  */
 export class AbstractDatabaseClient extends PuterClient {
     /** Short name used by `case()` to pick engine-specific values. */
@@ -52,9 +52,7 @@ export class AbstractDatabaseClient extends PuterClient {
     // Abstract interface — subclasses MUST override
     // ------------------------------------------------------------------
 
-    /**
-     * Execute a read query. Returns an array of row objects.
-     */
+    /** Execute a read query. Returns an array of row objects. */
     async read(
         _query: string,
         _params: unknown[] = [],
@@ -63,9 +61,9 @@ export class AbstractDatabaseClient extends PuterClient {
     }
 
     /**
-     * Read that prefers the primary database (useful when read-replicas
-     * may have replication lag). In single-node setups this is identical
-     * to `read()`.
+     * Read that prefers the primary database (useful when read-replicas may
+     * have replication lag). In single-node setups this is identical to
+     * `read()`.
      */
     async pread(
         _query: string,
@@ -74,16 +72,12 @@ export class AbstractDatabaseClient extends PuterClient {
         throw new Error('DatabaseClient.pread() not implemented');
     }
 
-    /**
-     * Execute a write query (INSERT / UPDATE / DELETE).
-     */
+    /** Execute a write query (INSERT / UPDATE / DELETE). */
     async write(_query: string, _params: unknown[] = []): Promise<WriteResult> {
         throw new Error('DatabaseClient.write() not implemented');
     }
 
-    /**
-     * Execute multiple write statements in a single transaction.
-     */
+    /** Execute multiple write statements in a single transaction. */
     async batchWrite(_entries: BatchEntry[]): Promise<void> {
         throw new Error('DatabaseClient.batchWrite() not implemented');
     }
@@ -111,9 +105,9 @@ export class AbstractDatabaseClient extends PuterClient {
     }
 
     /**
-     * Like `read()` but falls back to the primary when read-replicas are
-     * in use. Subclasses may override with replica-aware logic; the
-     * default delegates to `pread()`.
+     * Like `read()` but falls back to the primary when read-replicas are in
+     * use. Subclasses may override with replica-aware logic; the default
+     * delegates to `pread()`.
      */
     async tryHardRead(
         query: string,
@@ -133,9 +127,7 @@ export class AbstractDatabaseClient extends PuterClient {
         return primary;
     }
 
-    /**
-     * Like `tryHardRead()` but throws when the result set is empty.
-     */
+    /** Like `tryHardRead()` but throws when the result set is empty. */
     async requireRead(
         query: string,
         params: unknown[] = [],
@@ -151,9 +143,12 @@ export class AbstractDatabaseClient extends PuterClient {
      * Return the value from `choices` that matches the current engine.
      *
      * Usage:
-     * ```
-     * db.case({ sqlite: "datetime('now')", mysql: 'NOW()', otherwise: 'NOW()' })
-     * ```
+     *
+     *     db.case({
+     *         sqlite: "datetime('now')",
+     *         mysql: 'NOW()',
+     *         otherwise: 'NOW()',
+     *     });
      *
      * If the engine name isn't present in `choices`, falls back to
      * `choices.otherwise`.

src/backend/clients/database/MySQLDatabaseClient.test.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -17,13 +17,95 @@
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
-import { describe, expect, it, vi } from 'vitest';
+import { mkdtempSync, rmSync, writeFileSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
 import type { IConfig } from '../../types';
 import {
     MySQLDatabaseClient,
     compareMigrationFilenames,
 } from './MySQLDatabaseClient.js';
 
+interface FakeConnection {
+    query: ReturnType<typeof vi.fn>;
+    execute: ReturnType<typeof vi.fn>;
+    beginTransaction: ReturnType<typeof vi.fn>;
+    commit: ReturnType<typeof vi.fn>;
+    rollback: ReturnType<typeof vi.fn>;
+    release: ReturnType<typeof vi.fn>;
+}
+
+interface FakePool {
+    poolConfig: Record<string, unknown>;
+    connectionHandlers: ((conn: unknown) => void)[];
+    connections: FakeConnection[];
+    calls: { sql: string; values?: unknown[] }[];
+    ended: boolean;
+    endError: unknown;
+    endThrows: unknown;
+    respond: (sql: string, values?: unknown[]) => unknown;
+    on: (event: string, handler: (conn: unknown) => void) => FakePool;
+    promise: () => { getConnection: () => Promise<FakeConnection> };
+    end: (cb: (err?: unknown) => void) => void;
+}
+
+// mysql2 is the wire boundary: stub the driver's pool so we can assert on
+// the exact SQL, parameters and connection choreography the adapter emits.
+const { createPoolMock, createdPools } = vi.hoisted(() => {
+    const createdPools: FakePool[] = [];
+
+    const createPoolMock = vi.fn((poolConfig: Record<string, unknown>) => {
+        const pool: FakePool = {
+            poolConfig,
+            connectionHandlers: [],
+            connections: [],
+            calls: [],
+            ended: false,
+            endError: null,
+            endThrows: null,
+            respond: () => [[], undefined],
+            on(event, handler) {
+                if (event === 'connection') {
+                    pool.connectionHandlers.push(handler);
+                }
+                return pool;
+            },
+            promise() {
+                return {
+                    getConnection: async () => {
+                        const run = async (sql: string, values?: unknown[]) => {
+                            pool.calls.push({ sql, values });
+                            return pool.respond(sql, values);
+                        };
+                        const conn: FakeConnection = {
+                            query: vi.fn(run),
+                            execute: vi.fn(run),
+                            beginTransaction: vi.fn(async () => {}),
+                            commit: vi.fn(async () => {}),
+                            rollback: vi.fn(async () => {}),
+                            release: vi.fn(),
+                        };
+                        pool.connections.push(conn);
+                        return conn;
+                    },
+                };
+            },
+            end(cb) {
+                if (pool.endThrows) throw pool.endThrows;
+                pool.ended = true;
+                cb(pool.endError ?? undefined);
+            },
+        };
+        createdPools.push(pool);
+        return pool;
+    });
+
+    return { createPoolMock, createdPools };
+});
+
+vi.mock('mysql2', () => ({ createPool: createPoolMock }));
+
 describe('compareMigrationFilenames', () => {
     it('orders numbered migrations numerically, not lexically', () => {
         const input = [
@@ -132,7 +214,9 @@ const codedError = (code: string) => {
 
 describe('MySQLDatabaseClient.read — replica failover', () => {
     it('fails over to the primary on batcher load-shed errors', async () => {
-        const replica = { execute: vi.fn().mockRejectedValue(codedError('dbBatchFailed')) };
+        const replica = {
+            execute: vi.fn().mockRejectedValue(codedError('dbBatchFailed')),
+        };
         const primary = { execute: vi.fn().mockResolvedValue([[{ ok: 1 }]]) };
         const client = makeClient({ replica, primary });
 
@@ -141,7 +225,9 @@ describe('MySQLDatabaseClient.read — replica failover', () => {
     });
 
     it('fails over on transient connection errors', async () => {
-        const replica = { execute: vi.fn().mockRejectedValue(codedError('ECONNRESET')) };
+        const replica = {
+            execute: vi.fn().mockRejectedValue(codedError('ECONNRESET')),
+        };
         const primary = { execute: vi.fn().mockResolvedValue([[{ ok: 1 }]]) };
         const client = makeClient({ replica, primary });
 
@@ -149,7 +235,9 @@ describe('MySQLDatabaseClient.read — replica failover', () => {
     });
 
     it('rethrows deterministic SQL errors without touching the primary', async () => {
-        const replica = { execute: vi.fn().mockRejectedValue(codedError('ER_PARSE_ERROR')) };
+        const replica = {
+            execute: vi.fn().mockRejectedValue(codedError('ER_PARSE_ERROR')),
+        };
         const primary = { execute: vi.fn() };
         const client = makeClient({ replica, primary });
 
@@ -160,7 +248,9 @@ describe('MySQLDatabaseClient.read — replica failover', () => {
     });
 
     it('does not fail over in single-node configuration', async () => {
-        const replica = { execute: vi.fn().mockRejectedValue(codedError('dbBatchFailed')) };
+        const replica = {
+            execute: vi.fn().mockRejectedValue(codedError('dbBatchFailed')),
+        };
         const primary = { execute: vi.fn() };
         const client = makeClient({ replica, primary, multiNode: false });
 
@@ -170,3 +260,588 @@ describe('MySQLDatabaseClient.read — replica failover', () => {
         expect(primary.execute).not.toHaveBeenCalled();
     });
 });
+
+// -- Driver-level behaviour (stubbed mysql2 pool) ---------------------
+
+const mysqlConfig = (
+    database: Partial<NonNullable<IConfig['database']>> = {},
+): IConfig =>
+    ({
+        port: 0,
+        extensions: [],
+        database: { engine: 'mysql', ...database },
+    }) as IConfig;
+
+const startClient = async (
+    database: Partial<NonNullable<IConfig['database']>> = {},
+): Promise<MySQLDatabaseClient> => {
+    const client = new MySQLDatabaseClient(mysqlConfig(database));
+    await client.onServerStart();
+    return client;
+};
+
+// The batcher coalesces a batch into `stmt1;stmt2; SELECT 1`, so the driver
+// must answer with one row-set per statement plus one for the SELECT 1.
+const rowSets = (...sets: unknown[][]) => [[...sets, [{ 1: 1 }]], undefined];
+
+beforeEach(() => {
+    createdPools.length = 0;
+    createPoolMock.mockClear();
+});
+
+describe('MySQLDatabaseClient — pool construction', () => {
+    it('builds the primary pool from config with multi-statement support', async () => {
+        await startClient({
+            host: 'db.internal',
+            port: 3307,
+            user: 'puter',
+            password: 'hunter2',
+            database: 'puterdb',
+        });
+
+        expect(createPoolMock).toHaveBeenCalledTimes(1);
+        expect(createdPools[0].poolConfig).toEqual({
+            maxPreparedStatements: 900,
+            connectionLimit: 30,
+            enableKeepAlive: true,
+            host: 'db.internal',
+            port: 3307,
+            user: 'puter',
+            password: 'hunter2',
+            database: 'puterdb',
+            multipleStatements: true,
+        });
+    });
+
+    it('falls back to loopback defaults when the endpoint is unspecified', async () => {
+        await startClient();
+
+        expect(createdPools[0].poolConfig).toMatchObject({
+            host: '127.0.0.1',
+            port: 3306,
+            user: 'root',
+            password: '',
+            database: 'puter',
+        });
+    });
+
+    it('arms a server-side statement timeout on every new connection', async () => {
+        await startClient({ selectTimeoutMs: 12_000 });
+
+        const pool = createdPools[0];
+        expect(pool.connectionHandlers).toHaveLength(1);
+
+        const conn = { query: vi.fn() };
+        pool.connectionHandlers[0](conn);
+        expect(conn.query).toHaveBeenCalledWith(
+            'SET SESSION max_execution_time = 12000',
+        );
+    });
+
+    it('omits the statement timeout when configured to 0', async () => {
+        await startClient({ selectTimeoutMs: 0 });
+        expect(createdPools[0].connectionHandlers).toHaveLength(0);
+    });
+
+    it('shares one pool between reads and writes without a replica', async () => {
+        await startClient();
+        expect(createPoolMock).toHaveBeenCalledTimes(1);
+    });
+
+    it('creates a second pool when a read-replica is configured', async () => {
+        await startClient({
+            replica: { host: 'replica.internal', port: 3306 },
+        });
+
+        expect(createPoolMock).toHaveBeenCalledTimes(2);
+        expect(createdPools[1].poolConfig).toMatchObject({
+            host: 'replica.internal',
+            multipleStatements: true,
+        });
+    });
+});
+
+describe('MySQLDatabaseClient — query interface', () => {
+    it('sends the query and its parameters through to the driver', async () => {
+        const client = await startClient();
+        const pool = createdPools[0];
+        pool.respond = () => rowSets([{ id: 1, username: 'ada' }]);
+
+        await expect(
+            client.read('SELECT * FROM `user` WHERE `id` = ?', [1]),
+        ).resolves.toEqual([{ id: 1, username: 'ada' }]);
+
+        expect(pool.calls).toEqual([
+            {
+                sql: 'SELECT * FROM `user` WHERE `id` = ?; SELECT 1',
+                values: [1],
+            },
+        ]);
+    });
+
+    it('returns an empty array when the driver yields no row-set', async () => {
+        const client = await startClient();
+        createdPools[0].respond = () => [[], undefined];
+
+        await expect(client.read('SELECT 1')).resolves.toEqual([]);
+        await expect(client.pread('SELECT 1')).resolves.toEqual([]);
+    });
+
+    it('reads from the replica pool and primary-reads from the primary', async () => {
+        const client = await startClient({ replica: { host: 'replica' } });
+        const [primary, replica] = createdPools;
+        primary.respond = () => rowSets([{ from: 'primary' }]);
+        replica.respond = () => rowSets([{ from: 'replica' }]);
+
+        await expect(client.read('SELECT 1')).resolves.toEqual([
+            { from: 'replica' },
+        ]);
+        await expect(client.pread('SELECT 1')).resolves.toEqual([
+            { from: 'primary' },
+        ]);
+    });
+
+    it('maps the mysql result header onto the shared write result', async () => {
+        const client = await startClient();
+        createdPools[0].respond = () =>
+            rowSets({ insertId: 42, affectedRows: 2 } as unknown as unknown[]);
+
+        await expect(
+            client.write('UPDATE `user` SET `username` = ? WHERE `id` = ?', [
+                'ada',
+                1,
+            ]),
+        ).resolves.toEqual({
+            insertId: 42,
+            affectedRows: 2,
+            anyRowsAffected: true,
+        });
+    });
+
+    it('reports no rows affected when the header omits the counters', async () => {
+        const client = await startClient();
+        createdPools[0].respond = () => rowSets({} as unknown as unknown[]);
+
+        await expect(client.write('DELETE FROM `user`')).resolves.toEqual({
+            insertId: 0,
+            affectedRows: 0,
+            anyRowsAffected: false,
+        });
+    });
+
+    it('builds an INSERT with quoted identifiers and positional params', async () => {
+        const client = await startClient();
+        const pool = createdPools[0];
+        pool.respond = () =>
+            rowSets({ insertId: 7, affectedRows: 1 } as unknown as unknown[]);
+
+        await expect(
+            client.insert('user', { username: 'ada', email: null }),
+        ).resolves.toMatchObject({ insertId: 7 });
+
+        expect(pool.calls[0]).toEqual({
+            sql:
+                'INSERT INTO `user` (`username`, `email`) VALUES (?, ?); ' +
+                'SELECT 1',
+            values: ['ada', null],
+        });
+    });
+});
+
+describe('MySQLDatabaseClient — batchWrite transactions', () => {
+    it('runs every statement on one connection inside a transaction', async () => {
+        const client = await startClient();
+        const pool = createdPools[0];
+
+        await client.batchWrite([
+            { statement: 'UPDATE `user` SET `x` = ?', values: [1] },
+            {
+                statement: 'DELETE FROM `sessions` WHERE `uuid` = ?',
+                values: ['s'],
+            },
+        ]);
+
+        expect(pool.connections).toHaveLength(1);
+        const conn = pool.connections[0];
+        expect(conn.beginTransaction).toHaveBeenCalledTimes(1);
+        expect(conn.execute.mock.calls).toEqual([
+            ['UPDATE `user` SET `x` = ?', [1]],
+            ['DELETE FROM `sessions` WHERE `uuid` = ?', ['s']],
+        ]);
+        expect(conn.commit).toHaveBeenCalledTimes(1);
+        expect(conn.rollback).not.toHaveBeenCalled();
+        expect(conn.release).toHaveBeenCalledTimes(1);
+    });
+
+    it('rolls back and releases the connection when a statement fails', async () => {
+        const client = await startClient();
+        const pool = createdPools[0];
+        pool.respond = (sql) => {
+            if (sql.startsWith('DELETE')) throw new Error('constraint blew up');
+            return [[], undefined];
+        };
+
+        await expect(
+            client.batchWrite([
+                { statement: 'UPDATE `user` SET `x` = ?', values: [1] },
+                { statement: 'DELETE FROM `user`', values: [] },
+            ]),
+        ).rejects.toThrow('constraint blew up');
+
+        const conn = pool.connections[0];
+        expect(conn.commit).not.toHaveBeenCalled();
+        expect(conn.rollback).toHaveBeenCalledTimes(1);
+        expect(conn.release).toHaveBeenCalledTimes(1);
+    });
+
+    it('still rethrows the original failure when the rollback also fails', async () => {
+        const client = await startClient();
+        const pool = createdPools[0];
+        pool.respond = () => {
+            throw new Error('statement blew up');
+        };
+
+        const original = client.batchWrite([
+            { statement: 'UPDATE `user` SET `x` = ?', values: [1] },
+        ]);
+        // The rollback is attached after the connection is handed out, so
+        // patch it once the adapter has acquired one.
+        await Promise.resolve();
+        pool.connections[0]?.rollback.mockRejectedValue(
+            new Error('rollback blew up'),
+        );
+
+        await expect(original).rejects.toThrow('statement blew up');
+        expect(pool.connections[0].release).toHaveBeenCalledTimes(1);
+    });
+
+    it('never acquires a connection for an empty batch', async () => {
+        const client = await startClient();
+        await client.batchWrite([]);
+        expect(createdPools[0].connections).toHaveLength(0);
+    });
+});
+
+describe('MySQLDatabaseClient — tryHardRead', () => {
+    it('issues exactly one query in single-node configuration', async () => {
+        const client = await startClient();
+        const pool = createdPools[0];
+        pool.respond = () => rowSets([{ id: 1 }]);
+
+        await expect(client.tryHardRead('SELECT 1')).resolves.toEqual([
+            { id: 1 },
+        ]);
+        expect(pool.calls).toHaveLength(1);
+    });
+
+    it('prefers replica rows when the replica has them', async () => {
+        const client = await startClient({ replica: { host: 'replica' } });
+        const [primary, replica] = createdPools;
+        primary.respond = () => rowSets([{ from: 'primary' }]);
+        replica.respond = () => rowSets([{ from: 'replica' }]);
+
+        await expect(client.tryHardRead('SELECT 1')).resolves.toEqual([
+            { from: 'replica' },
+        ]);
+    });
+
+    it('falls back to the primary when the replica is behind', async () => {
+        const client = await startClient({ replica: { host: 'replica' } });
+        const [primary, replica] = createdPools;
+        primary.respond = () => rowSets([{ from: 'primary' }]);
+        replica.respond = () => rowSets([]);
+
+        await expect(client.tryHardRead('SELECT 1')).resolves.toEqual([
+            { from: 'primary' },
+        ]);
+    });
+
+    it('falls back to the primary when the replica query throws', async () => {
+        const client = await startClient({ replica: { host: 'replica' } });
+        const [primary, replica] = createdPools;
+        primary.respond = () => rowSets([{ from: 'primary' }]);
+        replica.respond = () => {
+            throw new Error('replica down');
+        };
+
+        await expect(client.tryHardRead('SELECT 1')).resolves.toEqual([
+            { from: 'primary' },
+        ]);
+    });
+});
+
+describe('MySQLDatabaseClient — migrations', () => {
+    let dir: string;
+
+    beforeEach(() => {
+        dir = mkdtempSync(join(tmpdir(), 'puter-mysql-mig-'));
+    });
+
+    afterEach(() => {
+        rmSync(dir, { recursive: true, force: true });
+    });
+
+    it('applies mysql migrations in numeric order, one statement at a time', async () => {
+        writeFileSync(
+            join(dir, 'mysql_mig_2.sql'),
+            'CREATE TABLE b (id INT);\nCREATE TABLE c (id INT);\n',
+        );
+        writeFileSync(
+            join(dir, 'mysql_mig_10.sql'),
+            'CREATE TABLE d (id INT);',
+        );
+        // Other engines' files and non-SQL noise must be ignored.
+        writeFileSync(join(dir, 'postgres_mig_1.sql'), 'CREATE TABLE nope ();');
+        writeFileSync(join(dir, 'mysql_notes.txt'), 'not sql');
+
+        await startClient({ migrationPaths: [dir] });
+
+        const pool = createdPools[0];
+        expect(pool.calls.map((c) => c.sql)).toEqual([
+            'CREATE TABLE b (id INT)',
+            'CREATE TABLE c (id INT)',
+            'CREATE TABLE d (id INT)',
+        ]);
+        expect(pool.connections[0].release).toHaveBeenCalledTimes(1);
+    });
+
+    it('reports which file and statement index failed', async () => {
+        writeFileSync(
+            join(dir, 'mysql_mig_1.sql'),
+            'CREATE TABLE ok (id INT);\nCREATE TABLE bad (id INT);',
+        );
+
+        const client = new MySQLDatabaseClient(
+            mysqlConfig({ migrationPaths: [dir] }),
+        );
+        const cause = new Error('ER_PARSE_ERROR');
+        // The pool only exists once onServerStart runs, so arm the failure
+        // through the factory.
+        createPoolMock.mockImplementationOnce((poolConfig) => {
+            const pool = createPoolMock.getMockImplementation()!(poolConfig);
+            pool.respond = (sql: string) => {
+                if (sql.includes('bad')) throw cause;
+                return [[], undefined];
+            };
+            return pool;
+        });
+
+        await expect(client.onServerStart()).rejects.toThrow(
+            '[mysql] failed to apply mysql_mig_1.sql at statement 1',
+        );
+    });
+
+    it('fails loudly when a configured migration path is unreadable', async () => {
+        await expect(
+            startClient({ migrationPaths: [join(dir, 'does-not-exist')] }),
+        ).rejects.toThrow('[mysql] migration path is unreadable');
+    });
+
+    it('skips a configured directory that holds no mysql migrations', async () => {
+        writeFileSync(join(dir, 'readme.md'), '# nothing here');
+        await startClient({ migrationPaths: [dir] });
+        expect(createdPools[0].calls).toEqual([]);
+    });
+});
+
+describe('MySQLDatabaseClient — pool lifecycle', () => {
+    it('replaces and closes the previous primary pool on reinit', async () => {
+        const client = await startClient();
+        const original = createdPools[0];
+
+        client.reinitPrimary();
+
+        expect(createdPools).toHaveLength(2);
+        expect(original.ended).toBe(true);
+        // Single-node: the replica batcher must follow the new primary.
+        createdPools[1].respond = () => rowSets([{ from: 'new-primary' }]);
+        await expect(client.read('SELECT 1')).resolves.toEqual([
+            { from: 'new-primary' },
+        ]);
+    });
+
+    it('replaces only the replica pool on replica reinit', async () => {
+        const client = await startClient({ replica: { host: 'replica' } });
+        const [primary, originalReplica] = createdPools;
+
+        client.reinitReplica();
+
+        expect(createdPools).toHaveLength(3);
+        expect(originalReplica.ended).toBe(true);
+        expect(primary.ended).toBe(false);
+    });
+
+    it('ignores a replica reinit when no replica is configured', async () => {
+        const client = await startClient();
+        client.reinitReplica();
+        expect(createdPools).toHaveLength(1);
+    });
+
+    it('ignores reinit once shutdown has started', async () => {
+        const client = await startClient();
+        await client.onServerPrepareShutdown();
+        client.reinitPrimary();
+        expect(createdPools).toHaveLength(1);
+        await client.onServerShutdown();
+    });
+
+    it('closes both pools on shutdown when a replica is configured', async () => {
+        const client = await startClient({ replica: { host: 'replica' } });
+        await client.onServerShutdown();
+
+        expect(createdPools[0].ended).toBe(true);
+        expect(createdPools[1].ended).toBe(true);
+    });
+
+    it('closes the pools once the drain window elapses', async () => {
+        vi.useFakeTimers();
+        try {
+            const client = await startClient();
+            await client.onServerPrepareShutdown();
+            expect(createdPools[0].ended).toBe(false);
+
+            await vi.advanceTimersByTimeAsync(60_000);
+            expect(createdPools[0].ended).toBe(true);
+        } finally {
+            vi.useRealTimers();
+        }
+    });
+
+    it('cancels the drain timer when shutdown arrives first', async () => {
+        vi.useFakeTimers();
+        try {
+            const client = await startClient();
+            await client.onServerPrepareShutdown();
+            // A second prepare is a no-op — only one drain timer may exist.
+            await client.onServerPrepareShutdown();
+            expect(vi.getTimerCount()).toBe(1);
+
+            await client.onServerShutdown();
+            expect(vi.getTimerCount()).toBe(0);
+            expect(createdPools[0].ended).toBe(true);
+        } finally {
+            vi.useRealTimers();
+        }
+    });
+
+    it('surfaces a driver error raised while closing the pool', async () => {
+        const client = await startClient();
+        createdPools[0].endError = new Error('pool refused to close');
+
+        await expect(client.onServerShutdown()).rejects.toThrow(
+            'pool refused to close',
+        );
+    });
+
+    it('surfaces a driver error thrown synchronously by end()', async () => {
+        const client = await startClient();
+        createdPools[0].endThrows = new Error('end exploded');
+
+        await expect(client.onServerShutdown()).rejects.toThrow('end exploded');
+    });
+});
+
+describe('MySQLDatabaseClient.readWithRetry', () => {
+    const codedFailure = (code: string) => {
+        const err = new Error(code) as Error & { code: string };
+        err.code = code;
+        return err;
+    };
+
+    it('classifies transient connection failures as retriable', () => {
+        expect(
+            MySQLDatabaseClient.isRetriableError(codedFailure('ECONNRESET')),
+        ).toBe(true);
+        expect(
+            MySQLDatabaseClient.isRetriableError(codedFailure('ER_DUP_ENTRY')),
+        ).toBe(false);
+        expect(
+            MySQLDatabaseClient.isRetriableError(new Error('Connection lost')),
+        ).toBe(true);
+    });
+
+    it('retries a transient failure and returns the eventual result', async () => {
+        const client = await startClient();
+        let attempts = 0;
+        const operation = vi.fn(async () => {
+            attempts += 1;
+            if (attempts < 3) throw codedFailure('PROTOCOL_CONNECTION_LOST');
+            return [{ ok: 1 }];
+        });
+
+        await expect(
+            client.readWithRetry('health', operation, { baseBackoffMs: 0 }),
+        ).resolves.toEqual([{ ok: 1 }]);
+        expect(operation).toHaveBeenCalledTimes(3);
+    });
+
+    it('gives up after the attempt budget is spent', async () => {
+        const client = await startClient();
+        const operation = vi.fn(async () => {
+            throw codedFailure('ETIMEDOUT');
+        });
+
+        await expect(
+            client.readWithRetry('health', operation, {
+                maxAttempts: 2,
+                baseBackoffMs: 0,
+            }),
+        ).rejects.toMatchObject({ code: 'ETIMEDOUT' });
+        expect(operation).toHaveBeenCalledTimes(2);
+    });
+
+    it('never retries a deterministic SQL error', async () => {
+        const client = await startClient();
+        const operation = vi.fn(async () => {
+            throw codedFailure('ER_PARSE_ERROR');
+        });
+
+        await expect(
+            client.readWithRetry('health', operation, { baseBackoffMs: 0 }),
+        ).rejects.toMatchObject({ code: 'ER_PARSE_ERROR' });
+        expect(operation).toHaveBeenCalledTimes(1);
+    });
+
+    it('stops retrying once shutdown has started', async () => {
+        const client = await startClient();
+        await client.onServerPrepareShutdown();
+        const operation = vi.fn(async () => {
+            throw codedFailure('ECONNRESET');
+        });
+
+        await expect(
+            client.readWithRetry('health', operation, { baseBackoffMs: 0 }),
+        ).rejects.toMatchObject({ code: 'ECONNRESET' });
+        expect(operation).toHaveBeenCalledTimes(1);
+        await client.onServerShutdown();
+    });
+
+    it('applies jittered exponential backoff capped at maxBackoffMs', async () => {
+        const client = await startClient();
+        const delays: number[] = [];
+        const realSetTimeout = globalThis.setTimeout;
+        const timeoutSpy = vi
+            .spyOn(globalThis, 'setTimeout')
+            .mockImplementation(((fn: () => void, ms?: number) => {
+                delays.push(ms ?? 0);
+                return realSetTimeout(fn, 0);
+            }) as typeof setTimeout);
+
+        try {
+            const operation = vi.fn(async () => {
+                throw codedFailure('ECONNRESET');
+            });
+            await expect(
+                client.readWithRetry('health', operation, {
+                    maxAttempts: 4,
+                    baseBackoffMs: 100,
+                    maxBackoffMs: 150,
+                    jitterRatio: 0,
+                }),
+            ).rejects.toMatchObject({ code: 'ECONNRESET' });
+            expect(delays).toEqual([100, 150, 150]);
+        } finally {
+            timeoutSpy.mockRestore();
+        }
+    });
+});

src/backend/clients/database/MySQLDatabaseClient.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -248,9 +248,9 @@ export class MySQLDatabaseClient extends AbstractDatabaseClient {
 
     /**
      * Apply `.sql` files from each configured migration directory in order.
-     * Files within a directory are sorted lexically. Files MUST be
-     * idempotent — there is no per-file applied-state tracking. Failures
-     * abort startup so operators see schema problems loud.
+     * Files within a directory are sorted lexically. Files MUST be idempotent —
+     * there is no per-file applied-state tracking. Failures abort startup so
+     * operators see schema problems loud.
      */
     private async runMigrations(): Promise<void> {
         const paths = this.config.database?.migrationPaths;
@@ -414,8 +414,10 @@ export class MySQLDatabaseClient extends AbstractDatabaseClient {
         return isRetriableError(error);
     }
 
-    /** Replica failures worth retrying on the primary: batcher load-shed
-     *  or transient connection errors — never deterministic SQL errors. */
+    /**
+     * Replica failures worth retrying on the primary: batcher load-shed or
+     * transient connection errors — never deterministic SQL errors.
+     */
     private static isFailoverWorthy(error: unknown): boolean {
         const code = (error as { code?: string })?.code;
         return code === 'dbBatchFailed' || isRetriableError(error);

src/backend/clients/database/PostgresDatabaseClient.integration.test.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.

src/backend/clients/database/PostgresDatabaseClient.test.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.

src/backend/clients/database/PostgresDatabaseClient.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.

src/backend/clients/database/SQLBatcher.js

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -89,20 +89,22 @@ export class SQLBatcher {
     #metricAttrs;
 
     /**
-     * @param {object} dbPool mysql2 pool
+     * @param {object} dbPool Mysql2 pool
      * @param {object} [opts]
-     * @param {number} [opts.maxTimeInQueue] ms an item may wait before flush
-     * @param {number} [opts.maxBatchSize] items coalesced per flush
-     * @param {number} [opts.maxQueueSize] drop-oldest high-water mark
-     * @param {number} [opts.failureThreshold] consecutive failures to open the breaker
-     * @param {number} [opts.cooldownMs] breaker open duration after last failure
-     * @param {'primary'|'replica'} [opts.poolLabel] role label on metrics; in
+     * @param {number} [opts.maxTimeInQueue] Ms an item may wait before flush
+     * @param {number} [opts.maxBatchSize] Items coalesced per flush
+     * @param {number} [opts.maxQueueSize] Drop-oldest high-water mark
+     * @param {number} [opts.failureThreshold] Consecutive failures to open the
+     *   breaker
+     * @param {number} [opts.cooldownMs] Breaker open duration after last
+     *   failure
+     * @param {'primary' | 'replica'} [opts.poolLabel] Role label on metrics; in
      *   single-node setups the 'replica' batcher shares the primary pool, so
      *   this reflects the read/write role rather than a physical instance
-     * @param {boolean} [opts.readOnly] this batcher only ever carries SELECTs,
+     * @param {boolean} [opts.readOnly] This batcher only ever carries SELECTs,
      *   so any transient failure is safe to retry
-     * @param {number} [opts.acquireTimeoutMs] max wait for a pooled
-     *   connection; 0 disables the bound
+     * @param {number} [opts.acquireTimeoutMs] Max wait for a pooled connection;
+     *   0 disables the bound
      */
     constructor(
         dbPool,

src/backend/clients/database/SQLBatcher.test.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.

src/backend/clients/database/SqliteDatabaseClient.test.ts

@@ -0,0 +1,437 @@
+/**
+ * Copyright (C) 2024-present Puter Technologies Inc.
+ *
+ * This file is part of Puter.
+ *
+ * Puter is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+import Database from 'better-sqlite3';
+import { existsSync, mkdtempSync, rmSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
+import type { IConfig } from '../../types';
+import { DatabaseClientFactory } from './index.js';
+import { SqliteDatabaseClient } from './SqliteDatabaseClient.js';
+
+/** Highest schema version the migration table can reach. */
+const CURRENT_SCHEMA_VERSION = 60;
+const SYSTEM_USER_UUID = '5d4adce0-a381-4982-9c02-6e2540026238';
+
+const sqliteConfig = (
+    database: Partial<NonNullable<IConfig['database']>> = {},
+): IConfig =>
+    ({
+        port: 0,
+        extensions: [],
+        database: { engine: 'sqlite', inMemory: true, ...database },
+    }) as IConfig;
+
+const bootClient = async (
+    database: Partial<NonNullable<IConfig['database']>> = {},
+): Promise<SqliteDatabaseClient> => {
+    const client = new SqliteDatabaseClient(sqliteConfig(database));
+    await client.onServerStart();
+    return client;
+};
+
+const userVersionOf = async (client: SqliteDatabaseClient): Promise<number> => {
+    const [row] = await client.read('PRAGMA user_version');
+    return row.user_version as number;
+};
+
+describe('SqliteDatabaseClient — boot and migrations', () => {
+    let client: SqliteDatabaseClient;
+
+    beforeEach(async () => {
+        client = await bootClient();
+    });
+
+    afterEach(() => {
+        client.onServerShutdown();
+    });
+
+    it('is what the factory picks for the sqlite engine', () => {
+        expect(new DatabaseClientFactory(sqliteConfig())).toBeInstanceOf(
+            SqliteDatabaseClient,
+        );
+    });
+
+    it('migrates a fresh database all the way to the current version', async () => {
+        expect(await userVersionOf(client)).toBe(CURRENT_SCHEMA_VERSION);
+    });
+
+    it('runs the javascript migrations, not just the .sql ones', async () => {
+        // The `system` user only exists because 0025 (a .dbmig.js file) ran
+        // inside the migration VM.
+        const rows = await client.read(
+            'SELECT `username` FROM `user` WHERE `uuid` = ?',
+            [SYSTEM_USER_UUID],
+        );
+        expect(rows).toEqual([{ username: 'system' }]);
+    });
+
+    it('leaves an already-migrated database untouched on a second boot', async () => {
+        const dir = mkdtempSync(join(tmpdir(), 'puter-sqlite-'));
+        const path = join(dir, 'nested', 'puter.sqlite');
+        try {
+            const first = new SqliteDatabaseClient(
+                sqliteConfig({ inMemory: false, path }),
+            );
+            await first.onServerStart();
+            await first.write(
+                'INSERT INTO `kv` (`user_id`, `kkey_hash`, `kkey`, `value`) ' +
+                    'VALUES (?, ?, ?, ?)',
+                [1, 1, 'boot-marker', '"kept"'],
+            );
+            first.onServerShutdown();
+
+            expect(existsSync(path)).toBe(true);
+
+            const second = new SqliteDatabaseClient(
+                sqliteConfig({ inMemory: false, path }),
+            );
+            await second.onServerStart();
+            await expect(
+                second.read('SELECT `value` FROM `kv` WHERE `kkey` = ?', [
+                    'boot-marker',
+                ]),
+            ).resolves.toEqual([{ value: '"kept"' }]);
+            expect(await userVersionOf(second)).toBe(CURRENT_SCHEMA_VERSION);
+            second.onServerShutdown();
+        } finally {
+            rmSync(dir, { recursive: true, force: true });
+        }
+    });
+
+    it('stops early at a configured target version', async () => {
+        const partial = await bootClient({ targetVersion: 5 });
+        try {
+            expect(await userVersionOf(partial)).toBe(5);
+            // 0005 landed (apps.background); 0011 (notification) did not.
+            await expect(
+                partial.read(
+                    "SELECT 1 FROM sqlite_master WHERE type = 'table' AND name = 'notification'",
+                ),
+            ).resolves.toEqual([]);
+            await expect(
+                partial.read(
+                    "SELECT 1 FROM pragma_table_info('apps') WHERE name = 'background'",
+                ),
+            ).resolves.toHaveLength(1);
+        } finally {
+            partial.onServerShutdown();
+        }
+    });
+});
+
+describe('SqliteDatabaseClient — legacy version inference', () => {
+    let dir: string;
+
+    beforeEach(() => {
+        dir = mkdtempSync(join(tmpdir(), 'puter-sqlite-legacy-'));
+    });
+
+    afterEach(() => {
+        rmSync(dir, { recursive: true, force: true });
+    });
+
+    it('treats user_version=0 with no bootstrap tables as uninitialized', async () => {
+        const path = join(dir, 'blank.sqlite');
+        new Database(path).close();
+
+        const warn = vi.spyOn(console, 'warn').mockImplementation(() => {});
+        const client = new SqliteDatabaseClient(
+            sqliteConfig({ inMemory: false, path }),
+        );
+        try {
+            await client.onServerStart();
+            expect(warn).toHaveBeenCalledWith(
+                expect.stringContaining('bootstrap tables are missing'),
+            );
+            // A full migration run followed, so the schema is current.
+            expect(await userVersionOf(client)).toBe(CURRENT_SCHEMA_VERSION);
+        } finally {
+            client.onServerShutdown();
+            warn.mockRestore();
+        }
+    });
+
+    it('infers the schema version from table and column markers', async () => {
+        const path = join(dir, 'legacy.sqlite');
+        const seed = new Database(path);
+        seed.exec(`
+            CREATE TABLE user (
+                id INTEGER PRIMARY KEY,
+                username TEXT,
+                otp_secret TEXT,
+                otp_enabled INTEGER,
+                otp_recovery_codes TEXT
+            );
+            CREATE TABLE apps (
+                id INTEGER PRIMARY KEY,
+                uid TEXT,
+                background INTEGER,
+                metadata TEXT
+            );
+            CREATE TABLE user_to_user_permissions (id INTEGER PRIMARY KEY);
+            CREATE TABLE audit_user_to_user_permissions (
+                id INTEGER PRIMARY KEY,
+                issuer_user_id INTEGER,
+                holder_user_id INTEGER
+            );
+            CREATE TABLE sessions (
+                id INTEGER PRIMARY KEY,
+                created_at INTEGER,
+                last_activity INTEGER
+            );
+            CREATE TABLE kv (id INTEGER PRIMARY KEY, value JSON);
+            INSERT INTO apps (uid)
+                VALUES ('app-e3ac5486-da8c-42ad-8377-8728086e0980');
+        `);
+        seed.close();
+
+        const warn = vi.spyOn(console, 'warn').mockImplementation(() => {});
+        // targetVersion just past the inferred version keeps the run a
+        // no-op, so the assertion is about inference alone.
+        const client = new SqliteDatabaseClient(
+            sqliteConfig({ inMemory: false, path, targetVersion: 22 }),
+        );
+        try {
+            await client.onServerStart();
+            expect(warn).toHaveBeenCalledWith(
+                '[sqlite] user_version=0; inferred legacy schema version 21',
+            );
+            // Nothing was applied, so user_version stays where it was.
+            expect(await userVersionOf(client)).toBe(0);
+        } finally {
+            client.onServerShutdown();
+            warn.mockRestore();
+        }
+    });
+
+    it('reports version 0 when only the bootstrap tables exist', async () => {
+        const path = join(dir, 'bootstrap-only.sqlite');
+        const seed = new Database(path);
+        seed.exec(`
+            CREATE TABLE user (id INTEGER PRIMARY KEY);
+            CREATE TABLE apps (id INTEGER PRIMARY KEY);
+        `);
+        seed.close();
+
+        const log = vi.spyOn(console, 'log').mockImplementation(() => {});
+        const client = new SqliteDatabaseClient(
+            sqliteConfig({ inMemory: false, path, targetVersion: 1 }),
+        );
+        try {
+            await client.onServerStart();
+            expect(log).toHaveBeenCalledWith('[sqlite] database version: 0');
+        } finally {
+            client.onServerShutdown();
+            log.mockRestore();
+        }
+    });
+});
+
+describe('SqliteDatabaseClient — query interface', () => {
+    let client: SqliteDatabaseClient;
+
+    beforeEach(async () => {
+        client = await bootClient();
+        await client.write(
+            'CREATE TABLE `widget` (`id` INTEGER PRIMARY KEY, ' +
+                '`name` TEXT, `enabled` INTEGER, `seen_at` TEXT)',
+        );
+    });
+
+    afterEach(() => {
+        client.onServerShutdown();
+    });
+
+    it('reports lastInsertRowid and change counts on write', async () => {
+        const inserted = await client.write(
+            'INSERT INTO `widget` (`name`) VALUES (?)',
+            ['spanner'],
+        );
+        expect(inserted).toEqual({
+            insertId: 1,
+            affectedRows: 1,
+            anyRowsAffected: true,
+        });
+
+        const missed = await client.write(
+            'UPDATE `widget` SET `name` = ? WHERE `id` = ?',
+            ['nope', 999],
+        );
+        expect(missed).toMatchObject({
+            affectedRows: 0,
+            anyRowsAffected: false,
+        });
+    });
+
+    it('binds booleans as sqlite integers', async () => {
+        await client.write(
+            'INSERT INTO `widget` (`name`, `enabled`) VALUES (?, ?)',
+            ['toggled', true],
+        );
+        await client.write(
+            'INSERT INTO `widget` (`name`, `enabled`) VALUES (?, ?)',
+            ['untoggled', false],
+        );
+
+        await expect(
+            client.read('SELECT `name`, `enabled` FROM `widget` ORDER BY `id`'),
+        ).resolves.toEqual([
+            { name: 'toggled', enabled: 1 },
+            { name: 'untoggled', enabled: 0 },
+        ]);
+    });
+
+    it('rewrites now() into the sqlite equivalent', async () => {
+        await client.write(
+            'INSERT INTO `widget` (`name`, `seen_at`) VALUES (?, NOW())',
+            ['stamped'],
+        );
+        const [row] = await client.read(
+            'SELECT `seen_at` FROM `widget` WHERE `name` = ?',
+            ['stamped'],
+        );
+        expect(row.seen_at).toMatch(/^\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}$/);
+    });
+
+    it('generates an INSERT from a data object', async () => {
+        await client.insert('widget', { name: 'generated', enabled: true });
+        await expect(
+            client.read('SELECT `name`, `enabled` FROM `widget`'),
+        ).resolves.toEqual([{ name: 'generated', enabled: 1 }]);
+    });
+
+    it('primary-reads through the same single-node connection', async () => {
+        await client.write('INSERT INTO `widget` (`name`) VALUES (?)', ['p']);
+        await expect(
+            client.pread('SELECT `name` FROM `widget`'),
+        ).resolves.toEqual([{ name: 'p' }]);
+    });
+
+    it('applies a batch write atomically', async () => {
+        await client.batchWrite([
+            {
+                statement:
+                    'INSERT INTO `widget` (`name`, `enabled`) VALUES (?, ?)',
+                values: ['one', true],
+            },
+            {
+                statement: 'INSERT INTO `widget` (`name`) VALUES (?)',
+                values: ['two'],
+            },
+        ]);
+
+        await expect(
+            client.read('SELECT `name` FROM `widget` ORDER BY `id`'),
+        ).resolves.toEqual([{ name: 'one' }, { name: 'two' }]);
+    });
+
+    it('rolls the whole batch back when one statement fails', async () => {
+        await expect(
+            client.batchWrite([
+                {
+                    statement: 'INSERT INTO `widget` (`name`) VALUES (?)',
+                    values: ['kept-if-broken'],
+                },
+                {
+                    statement: 'INSERT INTO `nonexistent` (`name`) VALUES (?)',
+                    values: ['boom'],
+                },
+            ]),
+        ).rejects.toThrow(/no such table/i);
+
+        await expect(
+            client.read('SELECT `name` FROM `widget`'),
+        ).resolves.toEqual([]);
+    });
+
+    it('surfaces sqlite errors for malformed SQL', async () => {
+        await expect(client.read('SELEC oops')).rejects.toThrow(
+            /syntax error/i,
+        );
+    });
+
+    it('closes the database on shutdown', async () => {
+        const closable = await bootClient();
+        closable.onServerShutdown();
+        await expect(closable.read('SELECT 1')).rejects.toThrow(
+            'The database connection is not open',
+        );
+    });
+});
+
+// Single-node engines have no replica to race, so `tryHardRead` must not
+// issue the query twice — the base-class default fires `pread()` and
+// `read()` in parallel, which on sqlite is the same connection.
+describe('SqliteDatabaseClient — tryHardRead', () => {
+    let client: SqliteDatabaseClient;
+
+    beforeEach(async () => {
+        client = await bootClient();
+        await client.write(
+            'CREATE TABLE `widget` (`id` INTEGER PRIMARY KEY, `name` TEXT)',
+        );
+    });
+
+    afterEach(() => {
+        client.onServerShutdown();
+    });
+
+    it('executes the statement exactly once', async () => {
+        await client.write('INSERT INTO `widget` (`name`) VALUES (?)', ['one']);
+        const readSpy = vi.spyOn(client, 'read');
+        const preadSpy = vi.spyOn(client, 'pread');
+
+        await expect(
+            client.tryHardRead('SELECT `name` FROM `widget`'),
+        ).resolves.toEqual([{ name: 'one' }]);
+
+        expect(readSpy).toHaveBeenCalledTimes(1);
+        expect(preadSpy).not.toHaveBeenCalled();
+    });
+
+    it('executes the statement exactly once when it matches no rows', async () => {
+        const readSpy = vi.spyOn(client, 'read');
+        const preadSpy = vi.spyOn(client, 'pread');
+
+        await expect(
+            client.tryHardRead('SELECT `name` FROM `widget`'),
+        ).resolves.toEqual([]);
+
+        expect(readSpy).toHaveBeenCalledTimes(1);
+        expect(preadSpy).not.toHaveBeenCalled();
+    });
+
+    it('throws from requireRead when nothing matches', async () => {
+        await expect(
+            client.requireRead(
+                'SELECT `name` FROM `widget` WHERE `id` = ?',
+                [42],
+            ),
+        ).rejects.toThrow('required read returned no rows');
+    });
+
+    it('returns the rows from requireRead when something matches', async () => {
+        await client.write('INSERT INTO `widget` (`name`) VALUES (?)', ['ok']);
+        await expect(
+            client.requireRead('SELECT `name` FROM `widget`'),
+        ).resolves.toEqual([{ name: 'ok' }]);
+    });
+});

src/backend/clients/database/SqliteDatabaseClient.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -27,9 +27,9 @@ import { AbstractDatabaseClient, type WriteResult } from './DatabaseClient';
 const MIGRATIONS_DIR = resolve(__dirname, './migrations/sqlite');
 
 /**
- * Ordered list of [threshold_version, files[]] pairs.
- * A database whose `user_version` is <= threshold_version will have
- * the corresponding files applied.
+ * Ordered list of [threshold_version, files[]] pairs. A database whose
+ * `user_version` is <= threshold_version will have the corresponding files
+ * applied.
  */
 const AVAILABLE_MIGRATIONS: [number, string[]][] = [
     [-1, ['0001_create-tables.sql', '0002_add-default-apps.sql']],
@@ -158,6 +158,16 @@ export class SqliteDatabaseClient extends AbstractDatabaseClient {
         return this.read(query, params);
     }
 
+    override async tryHardRead(
+        query: string,
+        params: unknown[] = [],
+    ): Promise<Record<string, unknown>[]> {
+        // No replica to race, so the base class's parallel
+        // primary-plus-replica read would run the same statement twice on
+        // the one connection.
+        return this.read(query, params);
+    }
+
     @Span('db.write', (query: string) => ({ 'db.statement': query }))
     override async write(
         query: string,

src/backend/clients/database/index.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -33,9 +33,9 @@ import { PostgresDatabaseClient } from './PostgresDatabaseClient';
 import { SqliteDatabaseClient } from './SqliteDatabaseClient';
 
 /**
- * Factory class registered in `puterClients`. PuterServer calls
- * `new DatabaseClientFactory(config)` — the constructor returns the
- * concrete subclass selected by `config.database.engine`.
+ * Factory class registered in `puterClients`. PuterServer calls `new
+ * DatabaseClientFactory(config)` — the constructor returns the concrete
+ * subclass selected by `config.database.engine`.
  */
 export const DatabaseClientFactory = class DatabaseClientFactory {
     constructor(config: IConfig) {

src/backend/clients/database/migrationFilenames.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.

src/backend/clients/database/preparePostgresSql.test.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.

src/backend/clients/database/preparePostgresSql.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.

src/backend/clients/database/retriableErrors.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -41,11 +41,10 @@ const RETRIABLE_ERROR_MESSAGES = [
 ];
 
 /**
- * Failures where the statement provably never reached the server, so a
- * retry can never double-apply it — safe even for writes. Anything that
- * can occur after the statement was sent (resets, protocol drops) is
- * deliberately excluded: the server may have committed before the
- * connection died.
+ * Failures where the statement provably never reached the server, so a retry
+ * can never double-apply it — safe even for writes. Anything that can occur
+ * after the statement was sent (resets, protocol drops) is deliberately
+ * excluded: the server may have committed before the connection died.
  */
 const NEVER_SENT_ERROR_CODES = new Set([
     'ECONNREFUSED',
@@ -59,10 +58,9 @@ const errorCode = (error: unknown): string | undefined =>
     (error as { code?: string } | null)?.code;
 
 /**
- * Transient connection-level failures worth retrying — but only for
- * statements that are safe to run twice (reads). Row-level errors
- * (duplicate key, constraint violations) are deterministic and never
- * match.
+ * Transient connection-level failures worth retrying — but only for statements
+ * that are safe to run twice (reads). Row-level errors (duplicate key,
+ * constraint violations) are deterministic and never match.
  */
 export const isRetriableError = (error: unknown): boolean => {
     const code = errorCode(error);

src/backend/clients/database/splitMysqlStatements.test.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.

src/backend/clients/database/splitMysqlStatements.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -20,12 +20,11 @@
 /**
  * DELIMITER-aware splitter for MySQL dump / migration files.
  *
- * Splits `sql` into individual statements using the active statement
- * delimiter (default `;`). Recognises `DELIMITER X` lines, single-quoted
- * strings, double-quoted strings, backtick-quoted identifiers, line
- * comments (`-- `, `#`) and block comments (`/* ... *\/`). DELIMITER
- * directives are stripped from the output (they're a client-side concept,
- * not server SQL).
+ * Splits `sql` into individual statements using the active statement delimiter
+ * (default `;`). Recognises `DELIMITER X` lines, single-quoted strings,
+ * double-quoted strings, backtick-quoted identifiers, line comments (`-- `,
+ * `#`) and block comments (`/* ... *\/`). DELIMITER directives are stripped
+ * from the output (they're a client-side concept, not server SQL).
  *
  * Returns trimmed, non-empty statements without the trailing delimiter.
  */

src/backend/clients/database/splitPostgresStatements.test.ts

@@ -0,0 +1,116 @@
+/**
+ * Copyright (C) 2024-present Puter Technologies Inc.
+ *
+ * This file is part of Puter.
+ *
+ * Puter is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+import { describe, expect, it } from 'vitest';
+import { splitPostgresStatements } from './splitPostgresStatements';
+
+describe('splitPostgresStatements', () => {
+    it('splits on semicolons and trims each statement', () => {
+        expect(
+            splitPostgresStatements('SELECT 1;\n  SELECT 2 ;\nSELECT 3'),
+        ).toEqual(['SELECT 1', 'SELECT 2', 'SELECT 3']);
+    });
+
+    it('drops empty statements from stray semicolons', () => {
+        expect(splitPostgresStatements(';;SELECT 1;;')).toEqual(['SELECT 1']);
+    });
+
+    it('returns nothing for whitespace-only input', () => {
+        expect(splitPostgresStatements('   \n\t ')).toEqual([]);
+    });
+
+    it('keeps semicolons inside single-quoted literals', () => {
+        expect(
+            splitPostgresStatements("INSERT INTO t VALUES ('a;b'); SELECT 1"),
+        ).toEqual(["INSERT INTO t VALUES ('a;b')", 'SELECT 1']);
+    });
+
+    it('handles doubled and backslash-escaped quotes in literals', () => {
+        expect(
+            splitPostgresStatements("SELECT 'it''s; fine'; SELECT 2"),
+        ).toEqual(["SELECT 'it''s; fine'", 'SELECT 2']);
+        expect(splitPostgresStatements("SELECT E'a\\'; b'; SELECT 2")).toEqual([
+            "SELECT E'a\\'; b'",
+            'SELECT 2',
+        ]);
+    });
+
+    it('keeps semicolons inside quoted identifiers', () => {
+        expect(
+            splitPostgresStatements('SELECT "we;ird" FROM t; SELECT 2'),
+        ).toEqual(['SELECT "we;ird" FROM t', 'SELECT 2']);
+    });
+
+    it('handles a doubled quote inside a quoted identifier', () => {
+        expect(
+            splitPostgresStatements('SELECT "we""ird;x" FROM t; SELECT 2'),
+        ).toEqual(['SELECT "we""ird;x" FROM t', 'SELECT 2']);
+    });
+
+    it('ignores semicolons inside line comments', () => {
+        expect(
+            splitPostgresStatements('SELECT 1 -- trailing; note\n; SELECT 2'),
+        ).toEqual(['SELECT 1 -- trailing; note', 'SELECT 2']);
+    });
+
+    it('ignores semicolons inside block comments', () => {
+        expect(
+            splitPostgresStatements('SELECT /* a; b */ 1; SELECT 2'),
+        ).toEqual(['SELECT /* a; b */ 1', 'SELECT 2']);
+    });
+
+    it('keeps a whole dollar-quoted function body together', () => {
+        const sql = [
+            'CREATE FUNCTION bump() RETURNS trigger AS $$',
+            'BEGIN',
+            '  NEW.updated_at := now();',
+            '  RETURN NEW;',
+            'END;',
+            '$$ LANGUAGE plpgsql;',
+            'SELECT 1',
+        ].join('\n');
+
+        const statements = splitPostgresStatements(sql);
+        expect(statements).toHaveLength(2);
+        expect(statements[0]).toContain('RETURN NEW;');
+        expect(statements[0].endsWith('$$ LANGUAGE plpgsql')).toBe(true);
+        expect(statements[1]).toBe('SELECT 1');
+    });
+
+    it('respects a tagged dollar quote and its nested untagged pair', () => {
+        const sql = 'SELECT $body$ inner $$ still; inside $body$; SELECT 2';
+        expect(splitPostgresStatements(sql)).toEqual([
+            'SELECT $body$ inner $$ still; inside $body$',
+            'SELECT 2',
+        ]);
+    });
+
+    it('treats a bare dollar sign as ordinary text', () => {
+        expect(splitPostgresStatements('SELECT 1 $ 2; SELECT 3')).toEqual([
+            'SELECT 1 $ 2',
+            'SELECT 3',
+        ]);
+    });
+
+    it('emits an unterminated final statement', () => {
+        expect(
+            splitPostgresStatements('SELECT 1; SELECT 2 -- no newline'),
+        ).toEqual(['SELECT 1', 'SELECT 2 -- no newline']);
+    });
+});

src/backend/clients/database/splitPostgresStatements.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.

src/backend/clients/dynamodb/DDBClient.test.ts

@@ -0,0 +1,531 @@
+/**
+ * Copyright (C) 2024-present Puter Technologies Inc.
+ *
+ * This file is part of Puter.
+ *
+ * Puter is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+import { createServer, type Server } from 'node:http';
+import type { AddressInfo } from 'node:net';
+import { afterAll, beforeAll, describe, expect, it, vi } from 'vitest';
+import type { IConfig } from '../../types';
+import { DDBClient } from './DDBClient';
+
+const TABLE = 'kv-items';
+const GSI = 'by-kind';
+
+const localConfig = (): IConfig =>
+    ({
+        port: 0,
+        extensions: [],
+        dynamo: { inMemory: true, bootstrapTables: true },
+    }) as unknown as IConfig;
+
+/**
+ * The emulator reports a table as CREATING for a tick after `CreateTable`
+ * returns, so wait until it actually answers a read before using it.
+ */
+const awaitTable = async (
+    client: DDBClient,
+    table: string,
+    key: Record<string, unknown>,
+): Promise<void> => {
+    for (let attempt = 0; attempt < 100; attempt++) {
+        try {
+            await client.get(table, key);
+            return;
+        } catch (error) {
+            if ((error as Error).name !== 'ResourceNotFoundException')
+                throw error;
+            await new Promise((resolve) => setTimeout(resolve, 20));
+        }
+    }
+    throw new Error(`table ${table} never became queryable`);
+};
+
+const tableSchema = {
+    TableName: TABLE,
+    KeySchema: [
+        { AttributeName: 'pk', KeyType: 'HASH' as const },
+        { AttributeName: 'sk', KeyType: 'RANGE' as const },
+    ],
+    AttributeDefinitions: [
+        { AttributeName: 'pk', AttributeType: 'S' as const },
+        { AttributeName: 'sk', AttributeType: 'S' as const },
+        { AttributeName: 'kind', AttributeType: 'S' as const },
+    ],
+    GlobalSecondaryIndexes: [
+        {
+            IndexName: GSI,
+            KeySchema: [{ AttributeName: 'kind', KeyType: 'HASH' as const }],
+            Projection: { ProjectionType: 'ALL' as const },
+            ProvisionedThroughput: {
+                ReadCapacityUnits: 5,
+                WriteCapacityUnits: 5,
+            },
+        },
+    ],
+    ProvisionedThroughput: { ReadCapacityUnits: 5, WriteCapacityUnits: 5 },
+};
+
+describe('DDBClient — item operations', () => {
+    let client: DDBClient;
+
+    beforeAll(async () => {
+        client = new DDBClient(localConfig());
+        await client.createTableIfNotExists(tableSchema);
+        await awaitTable(client, TABLE, { pk: 'ready', sk: 'ready' });
+    });
+
+    it('round-trips an item and reports consumed capacity', async () => {
+        await client.put(TABLE, { pk: 'u1', sk: 'profile', name: 'ada' });
+
+        const result = await client.get(TABLE, { pk: 'u1', sk: 'profile' });
+        expect(result.Item).toEqual({ pk: 'u1', sk: 'profile', name: 'ada' });
+        expect(result.ConsumedCapacity?.TableName).toBe(TABLE);
+    });
+
+    it('returns no Item for a key that does not exist', async () => {
+        const result = await client.get(TABLE, { pk: 'nobody', sk: 'here' });
+        expect(result.Item).toBeUndefined();
+    });
+
+    it('honours a strongly consistent read', async () => {
+        await client.put(TABLE, { pk: 'u2', sk: 'profile', name: 'grace' });
+        const result = await client.get(
+            TABLE,
+            { pk: 'u2', sk: 'profile' },
+            true,
+        );
+        expect(result.Item?.name).toBe('grace');
+    });
+
+    it('applies an update expression and returns the new item', async () => {
+        await client.put(TABLE, { pk: 'u3', sk: 'counter', hits: 1 });
+        const updated = await client.update(
+            TABLE,
+            { pk: 'u3', sk: 'counter' },
+            'SET #h = :next',
+            { ':next': 5 },
+            { '#h': 'hits' },
+        );
+        expect(updated.Attributes).toMatchObject({ hits: 5 });
+    });
+
+    it('supports an update expression with no values or names', async () => {
+        await client.put(TABLE, { pk: 'u4', sk: 'doc', stale: true });
+        const updated = await client.update(
+            TABLE,
+            { pk: 'u4', sk: 'doc' },
+            'REMOVE stale',
+        );
+        expect(updated.Attributes).toEqual({ pk: 'u4', sk: 'doc' });
+    });
+
+    it('deletes an item', async () => {
+        await client.put(TABLE, { pk: 'u5', sk: 'temp' });
+        await client.del(TABLE, { pk: 'u5', sk: 'temp' });
+        const result = await client.get(TABLE, { pk: 'u5', sk: 'temp' });
+        expect(result.Item).toBeUndefined();
+    });
+
+    it('fetches keys from several tables in one batch', async () => {
+        await client.put(TABLE, { pk: 'b1', sk: 'a', v: 1 });
+        await client.put(TABLE, { pk: 'b1', sk: 'b', v: 2 });
+
+        const result = await client.batchGet([
+            { table: TABLE, items: { pk: 'b1', sk: 'a' } },
+            { table: TABLE, items: { pk: 'b1', sk: 'b' } },
+        ]);
+
+        const values = (result.Responses?.[TABLE] ?? [])
+            .map((item) => item.v as number)
+            .sort();
+        expect(values).toEqual([1, 2]);
+    });
+});
+
+describe('DDBClient — queries', () => {
+    let client: DDBClient;
+
+    beforeAll(async () => {
+        client = new DDBClient(localConfig());
+        await client.createTableIfNotExists(tableSchema);
+        await awaitTable(client, TABLE, { pk: 'ready', sk: 'ready' });
+        for (const sk of ['post#1', 'post#2', 'post#3', 'note#1']) {
+            await client.put(TABLE, {
+                pk: 'q1',
+                sk,
+                kind: sk.split('#')[0],
+                size: sk === 'post#2' ? 10 : 1,
+            });
+        }
+    });
+
+    it('queries by partition key', async () => {
+        const result = await client.query(TABLE, { pk: 'q1' });
+        expect(result.Items).toHaveLength(4);
+        expect(result.ConsumedCapacity?.TableName).toBe(TABLE);
+    });
+
+    it('narrows the sort key with begins_with', async () => {
+        const result = await client.query(
+            TABLE,
+            { pk: 'q1' },
+            0,
+            undefined,
+            '',
+            false,
+            { beginsWith: { key: 'sk', value: 'post#' } },
+        );
+        expect(result.Items?.map((item) => item.sk)).toEqual([
+            'post#1',
+            'post#2',
+            'post#3',
+        ]);
+    });
+
+    it('ignores an empty begins_with value', async () => {
+        const result = await client.query(
+            TABLE,
+            { pk: 'q1' },
+            0,
+            undefined,
+            '',
+            false,
+            { beginsWith: { key: 'sk', value: '' } },
+        );
+        expect(result.Items).toHaveLength(4);
+    });
+
+    it('applies a filter expression with its own names and values', async () => {
+        const result = await client.query(
+            TABLE,
+            { pk: 'q1' },
+            0,
+            undefined,
+            '',
+            false,
+            {
+                filter: {
+                    expression: '#s > :min',
+                    names: { '#s': 'size' },
+                    values: { ':min': 5 },
+                },
+            },
+        );
+        expect(result.Items?.map((item) => item.sk)).toEqual(['post#2']);
+    });
+
+    it('counts without returning items', async () => {
+        const result = await client.query(
+            TABLE,
+            { pk: 'q1' },
+            0,
+            undefined,
+            '',
+            false,
+            { select: 'COUNT' },
+        );
+        expect(result.Count).toBe(4);
+        expect(result.Items).toBeUndefined();
+    });
+
+    it('pages through results with the last evaluated key', async () => {
+        const seen: string[] = [];
+        let pageKey: Record<string, unknown> | undefined;
+        let pages = 0;
+
+        do {
+            const page = await client.query(TABLE, { pk: 'q1' }, 2, pageKey);
+            pages += 1;
+            expect(page.Items?.length).toBeLessThanOrEqual(2);
+            for (const item of page.Items ?? []) seen.push(item.sk as string);
+            pageKey = page.LastEvaluatedKey;
+        } while (pageKey && pages < 10);
+
+        expect(pages).toBeGreaterThan(1);
+        expect(new Set(seen).size).toBe(4);
+    });
+
+    it('queries a secondary index', async () => {
+        const result = await client.query(
+            TABLE,
+            { kind: 'note' },
+            0,
+            undefined,
+            GSI,
+        );
+        expect(result.Items?.map((item) => item.sk)).toEqual(['note#1']);
+    });
+});
+
+describe('DDBClient — batch writes', () => {
+    let client: DDBClient;
+
+    beforeAll(async () => {
+        client = new DDBClient(localConfig());
+        await client.createTableIfNotExists(tableSchema);
+        await awaitTable(client, TABLE, { pk: 'ready', sk: 'ready' });
+    });
+
+    it('reports no consumed capacity for an empty batch', async () => {
+        await expect(client.batchPut([])).resolves.toEqual({
+            ConsumedCapacity: [],
+        });
+    });
+
+    it('splits a batch larger than the service limit into chunks', async () => {
+        const params = Array.from({ length: 60 }, (_, index) => ({
+            table: TABLE,
+            item: { pk: 'bulk', sk: `item-${index}`, index },
+        }));
+
+        const result = await client.batchPut(params);
+
+        expect(result.ConsumedCapacity).toHaveLength(1);
+        expect(result.ConsumedCapacity[0].TableName).toBe(TABLE);
+        expect(result.ConsumedCapacity[0].CapacityUnits).toBeGreaterThan(0);
+
+        const stored = await client.query(TABLE, { pk: 'bulk' });
+        expect(stored.Items).toHaveLength(60);
+    });
+});
+
+describe('DDBClient — expired item sweep', () => {
+    it('deletes only the items past their ttl when the table already existed', async () => {
+        const client = new DDBClient(localConfig());
+        const table = 'ttl-items';
+        const schema = {
+            TableName: table,
+            KeySchema: [{ AttributeName: 'pk', KeyType: 'HASH' as const }],
+            AttributeDefinitions: [
+                { AttributeName: 'pk', AttributeType: 'S' as const },
+            ],
+            ProvisionedThroughput: {
+                ReadCapacityUnits: 5,
+                WriteCapacityUnits: 5,
+            },
+        };
+
+        await client.createTableIfNotExists(schema, 'expireAt');
+        await awaitTable(client, table, { pk: 'ready' });
+        const now = Math.floor(Date.now() / 1000);
+        await client.put(table, { pk: 'stale', expireAt: now - 60 });
+        await client.put(table, { pk: 'fresh', expireAt: now + 3600 });
+        await client.put(table, { pk: 'eternal' });
+
+        // Second call finds the table in use, so the sweep runs.
+        await client.createTableIfNotExists(schema, 'expireAt');
+
+        expect((await client.get(table, { pk: 'stale' })).Item).toBeUndefined();
+        expect((await client.get(table, { pk: 'fresh' })).Item).toBeDefined();
+        expect((await client.get(table, { pk: 'eternal' })).Item).toBeDefined();
+    });
+});
+
+describe('DDBClient — expired item sweep on an empty table', () => {
+    it('completes without deleting anything', async () => {
+        const client = new DDBClient(localConfig());
+        const table = 'ttl-empty';
+        const schema = {
+            TableName: table,
+            KeySchema: [{ AttributeName: 'pk', KeyType: 'HASH' as const }],
+            AttributeDefinitions: [
+                { AttributeName: 'pk', AttributeType: 'S' as const },
+            ],
+            ProvisionedThroughput: {
+                ReadCapacityUnits: 5,
+                WriteCapacityUnits: 5,
+            },
+        };
+
+        await client.createTableIfNotExists(schema, 'expireAt');
+        await awaitTable(client, table, { pk: 'ready' });
+        await expect(
+            client.createTableIfNotExists(schema, 'expireAt'),
+        ).resolves.toBeUndefined();
+    });
+});
+
+describe('DDBClient — credentialled configuration', () => {
+    it('refuses an aws config that is missing a key', () => {
+        expect(
+            () =>
+                new DDBClient({
+                    port: 0,
+                    extensions: [],
+                    dynamo: { aws: { access_key: 'only-one' } },
+                } as unknown as IConfig),
+        ).toThrow('requires both `access_key` and `secret_key`');
+    });
+
+    it('skips table creation on a managed deployment', async () => {
+        const warn = vi.spyOn(console, 'warn').mockImplementation(() => {});
+        const client = new DDBClient({
+            port: 0,
+            extensions: [],
+            dynamo: {
+                aws: { access_key: 'a', secret_key: 'b', region: 'us-west-2' },
+                endpoint: 'http://127.0.0.1:1',
+            },
+        } as unknown as IConfig);
+
+        // Would fail against the unreachable endpoint if it actually tried.
+        await client.createTableIfNotExists(tableSchema);
+        expect(warn).toHaveBeenCalledWith(
+            expect.stringContaining(
+                'Creating DynamoDB tables is disabled by default',
+            ),
+        );
+        warn.mockRestore();
+    });
+
+    it('rebinds an aws-credentialled client on recreate', async () => {
+        const client = new DDBClient({
+            port: 0,
+            extensions: [],
+            dynamo: {
+                aws: { access_key: 'a', secret_key: 'b' },
+                endpoint: 'http://127.0.0.1:1',
+            },
+        } as unknown as IConfig);
+
+        await expect(client.recreateClient()).resolves.toBeUndefined();
+    });
+
+    it('rebinds the underlying client on recreate', async () => {
+        const client = new DDBClient(localConfig());
+        await client.createTableIfNotExists(tableSchema);
+        await awaitTable(client, TABLE, { pk: 'ready', sk: 'ready' });
+        await client.put(TABLE, { pk: 'recreate', sk: 'a', v: 1 });
+
+        await client.recreateClient();
+
+        // Same in-memory store: the recreated client sees earlier writes.
+        const result = await client.get(TABLE, { pk: 'recreate', sk: 'a' });
+        expect(result.Item?.v).toBe(1);
+    });
+});
+
+// Unprocessed items are a throttling signal the emulator never produces, so
+// the retry loop is driven against a stub speaking the DynamoDB wire format.
+describe('DDBClient — unprocessed batch items', () => {
+    let server: Server;
+    let endpoint: string;
+    let responses: unknown[];
+    let requestCount = 0;
+
+    beforeAll(async () => {
+        server = createServer((req, res) => {
+            let body = '';
+            req.on('data', (chunk) => {
+                body += chunk;
+            });
+            req.on('end', () => {
+                const next = responses.shift() ?? {};
+                requestCount += 1;
+                res.writeHead(200, {
+                    'content-type': 'application/x-amz-json-1.0',
+                });
+                res.end(JSON.stringify(next));
+            });
+        });
+        await new Promise<void>((resolve) =>
+            server.listen(0, '127.0.0.1', resolve),
+        );
+        endpoint = `http://127.0.0.1:${(server.address() as AddressInfo).port}`;
+    });
+
+    afterAll(async () => {
+        await new Promise<void>((resolve) => server.close(() => resolve()));
+    });
+
+    const stubClient = () =>
+        new DDBClient({
+            port: 0,
+            extensions: [],
+            dynamo: {
+                aws: { access_key: 'a', secret_key: 'b', region: 'us-west-2' },
+                endpoint,
+            },
+        } as unknown as IConfig);
+
+    const unprocessed = (pk: string) => ({
+        UnprocessedItems: {
+            [TABLE]: [{ PutRequest: { Item: { pk: { S: pk } } } }],
+        },
+        ConsumedCapacity: [{ TableName: TABLE, CapacityUnits: 1 }],
+    });
+
+    it('retries the leftover items and sums capacity across attempts', async () => {
+        requestCount = 0;
+        responses = [
+            unprocessed('retry-me'),
+            {
+                UnprocessedItems: {},
+                ConsumedCapacity: [{ TableName: TABLE, CapacityUnits: 2 }],
+            },
+        ];
+
+        const result = await stubClient().batchPut([
+            { table: TABLE, item: { pk: 'retry-me' } },
+        ]);
+
+        expect(requestCount).toBe(2);
+        expect(result.ConsumedCapacity).toEqual([
+            { TableName: TABLE, CapacityUnits: 3 },
+        ]);
+    });
+
+    it('gives up with a bad-request error when items never drain', async () => {
+        requestCount = 0;
+        responses = Array.from({ length: 12 }, () => unprocessed('stuck'));
+
+        await expect(
+            stubClient().batchPut([{ table: TABLE, item: { pk: 'stuck' } }]),
+        ).rejects.toMatchObject({
+            statusCode: 400,
+            legacyCode: 'bad_request',
+            message: 'Failed to batch write all items to DynamoDB',
+        });
+        // One initial attempt plus the full retry budget.
+        expect(requestCount).toBe(9);
+    }, 30_000);
+
+    it('tolerates a response that reports no capacity at all', async () => {
+        requestCount = 0;
+        responses = [{ UnprocessedItems: {} }];
+
+        await expect(
+            stubClient().batchPut([{ table: TABLE, item: { pk: 'quiet' } }]),
+        ).resolves.toEqual({ ConsumedCapacity: [] });
+        expect(requestCount).toBe(1);
+    });
+
+    it('ignores capacity entries with no table name', async () => {
+        requestCount = 0;
+        responses = [
+            {
+                UnprocessedItems: {},
+                ConsumedCapacity: [{ CapacityUnits: 7 }],
+            },
+        ];
+
+        await expect(
+            stubClient().batchPut([{ table: TABLE, item: { pk: 'anon' } }]),
+        ).resolves.toEqual({ ConsumedCapacity: [] });
+    });
+});

src/backend/clients/dynamodb/DDBClient.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -453,6 +453,7 @@ export class DDBClient extends PuterClient {
             return;
         }
 
+        let alreadyExisted = false;
         try {
             const client = await this.#getDocumentClient();
             await client.send(new CreateTableCommand(params));
@@ -460,14 +461,33 @@ export class DDBClient extends PuterClient {
             if ((error as Error)?.name !== 'ResourceInUseException') {
                 throw error;
             }
+            alreadyExisted = true;
         }
 
-        if (ttlAttribute) {
-            await this.#deleteExpiredItems(
-                params.TableName!,
-                params.KeySchema!,
-                ttlAttribute,
-            );
+        // Only sweep a table that was already there. `CreateTable` returns
+        // while the table is still CREATING, so scanning it right away races
+        // its transition to ACTIVE and intermittently throws
+        // `ResourceNotFoundException` — and a table we just created holds no
+        // items to expire anyway.
+        if (ttlAttribute && alreadyExisted) {
+            try {
+                await this.#deleteExpiredItems(
+                    params.TableName!,
+                    params.KeySchema!,
+                    ttlAttribute,
+                );
+            } catch (error) {
+                // The sweep is opportunistic cleanup, so a table that isn't
+                // queryable yet must never fail boot. Emulators differ on
+                // whether `CreateTable` reports an existing table as in-use,
+                // which can still land us here on a CREATING table.
+                if ((error as Error)?.name !== 'ResourceNotFoundException') {
+                    throw error;
+                }
+                console.warn(
+                    `[ddb] skipped TTL sweep for ${params.TableName}: table not queryable yet`,
+                );
+            }
         }
     }
 

src/backend/clients/email/EmailClient.test.ts

@@ -0,0 +1,299 @@
+/**
+ * Copyright (C) 2024-present Puter Technologies Inc.
+ *
+ * This file is part of Puter.
+ *
+ * Puter is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+import { describe, expect, it, vi } from 'vitest';
+import type { IConfig } from '../../types';
+import { EmailClient } from './EmailClient';
+
+const FROM = '"Puter" <[email protected]>';
+
+/**
+ * Nodemailer's JSON transport is a real transport that serializes the message
+ * instead of talking SMTP — the send path stays genuine while the wire stays
+ * local.
+ */
+const jsonTransportConfig = (overrides: Partial<IConfig> = {}): IConfig =>
+    ({
+        port: 0,
+        extensions: [],
+        env: 'prod',
+        email: { jsonTransport: true, from: FROM },
+        ...overrides,
+    }) as unknown as IConfig;
+
+const startClient = (overrides: Partial<IConfig> = {}): EmailClient => {
+    const client = new EmailClient(jsonTransportConfig(overrides));
+    client.onServerStart();
+    return client;
+};
+
+/** The JSON transport reports the serialized message on `.message`. */
+const sentMessage = (info: unknown) =>
+    JSON.parse((info as { message: string }).message) as {
+        from: { address: string; name: string };
+        to: { address: string }[];
+        subject: string;
+        html?: string;
+        headers?: Record<string, string>;
+    };
+
+describe('EmailClient — transport lifecycle', () => {
+    it('reports as configured once a transport is wired up', () => {
+        const client = startClient();
+        expect(client.isConfigured).toBe(true);
+        client.onServerShutdown();
+        expect(client.isConfigured).toBe(false);
+    });
+
+    it('warns and stays unconfigured when no transport is set', () => {
+        const warn = vi.spyOn(console, 'warn').mockImplementation(() => {});
+        const client = new EmailClient({
+            port: 0,
+            extensions: [],
+        } as unknown as IConfig);
+        client.onServerStart();
+
+        expect(client.isConfigured).toBe(false);
+        expect(warn).toHaveBeenCalledWith(
+            expect.stringContaining('no email transport configured'),
+        );
+        warn.mockRestore();
+    });
+
+    it('drops the send and returns null when no transport exists', async () => {
+        const warn = vi.spyOn(console, 'warn').mockImplementation(() => {});
+        const client = new EmailClient({
+            port: 0,
+            extensions: [],
+        } as unknown as IConfig);
+        client.onServerStart();
+
+        await expect(
+            client.sendRaw({ to: '[email protected]', subject: 'hi', text: 'hi' }),
+        ).resolves.toBeNull();
+        expect(warn).toHaveBeenCalledWith(
+            expect.stringContaining('without transport'),
+            expect.objectContaining({ to: '[email protected]' }),
+        );
+        warn.mockRestore();
+    });
+});
+
+describe('EmailClient — sending', () => {
+    it('sends a rendered template through the transport', async () => {
+        const client = startClient();
+        const info = await client.sendRaw({
+            to: '[email protected]',
+            subject: 'raw subject',
+            html: '<p>hello</p>',
+            headers: { 'List-Unsubscribe': '<https://puter.test/u>' },
+        });
+
+        const message = sentMessage(info);
+        expect(message.subject).toBe('raw subject');
+        expect(message.to[0].address).toBe('[email protected]');
+        expect(message.from.address).toBe('[email protected]');
+        expect(message.headers?.['List-Unsubscribe']).toBe(
+            '<https://puter.test/u>',
+        );
+    });
+
+    it('lets the caller override the from address', async () => {
+        const client = startClient();
+        const info = await client.sendRaw({
+            from: '[email protected]',
+            to: '[email protected]',
+            subject: 's',
+            text: 't',
+        });
+        expect(sentMessage(info).from.address).toBe('[email protected]');
+    });
+
+    it('falls back to the built-in sender when config has none', async () => {
+        const client = startClient({
+            email: { jsonTransport: true },
+        } as unknown as Partial<IConfig>);
+        const info = await client.sendRaw({
+            to: '[email protected]',
+            subject: 's',
+            text: 't',
+        });
+        expect(sentMessage(info).from.address).toBe('[email protected]');
+    });
+
+    it('refuses an unknown template name', async () => {
+        const client = startClient();
+        await expect(
+            client.send('[email protected]', 'not-a-template' as never),
+        ).rejects.toThrow('Unknown email template: not-a-template');
+    });
+
+    it('surfaces transport failures to the caller', async () => {
+        // Port 1 on loopback is never listening, so the send really fails.
+        const client = startClient({
+            email: { host: '127.0.0.1', port: 1, from: FROM },
+        } as unknown as Partial<IConfig>);
+
+        await expect(
+            client.sendRaw({
+                to: '[email protected]',
+                subject: 's',
+                text: 't',
+            }),
+        ).rejects.toThrow();
+    });
+});
+
+describe('EmailClient — template rendering', () => {
+    it('renders the code into both subject and body', async () => {
+        const client = startClient();
+        const captured: { subject?: string; html?: string } = {};
+        const original = client.sendRaw.bind(client);
+        vi.spyOn(client, 'sendRaw').mockImplementation(async (options) => {
+            captured.subject = options.subject;
+            captured.html = options.html;
+            return original(options);
+        });
+
+        await client.send('[email protected]', 'email_verification_code', {
+            code: '424242',
+        });
+
+        expect(captured.subject).toBe('424242 is your confirmation code');
+        expect(captured.html).toContain('<strong>424242</strong>');
+    });
+
+    it('escapes html and converts newlines in nl2br values', async () => {
+        const client = startClient();
+        let html = '';
+        vi.spyOn(client, 'sendRaw').mockImplementation(async (options) => {
+            html = options.html ?? '';
+            return null;
+        });
+
+        await client.send('[email protected]', 'listing-rejected', {
+            app_name: 'demo',
+            app_title: 'Demo',
+            reason: 'first & "only"\n<b>line</b>',
+        });
+
+        expect(html).toContain(
+            'first &amp; &quot;only&quot;<br />&lt;b&gt;line&lt;/b&gt;',
+        );
+    });
+
+    it('renders an empty string for a missing nl2br value', async () => {
+        const client = startClient();
+        let html = '';
+        vi.spyOn(client, 'sendRaw').mockImplementation(async (options) => {
+            html = options.html ?? '';
+            return null;
+        });
+
+        await client.send('[email protected]', 'listing-rejected', {
+            app_name: 'demo',
+            app_title: 'Demo',
+        });
+
+        expect(html).toContain('<blockquote></blockquote>');
+    });
+});
+
+describe('EmailClient.clean', () => {
+    const clean = (email: string) => startClient().clean(email);
+
+    it('strips subaddressing on ordinary domains', () => {
+        expect(clean('[email protected]')).toBe('[email protected]');
+    });
+
+    it('ignores dots and subaddressing for gmail', () => {
+        expect(clean('[email protected]')).toBe('[email protected]');
+    });
+
+    it('canonicalizes googlemail onto gmail', () => {
+        expect(clean('[email protected]')).toBe('[email protected]');
+    });
+
+    it('keeps yahoo subaddressing, which yahoo treats as distinct', () => {
+        expect(clean('[email protected]')).toBe('[email protected]');
+    });
+
+    it('ignores dots for icloud aliases', () => {
+        expect(clean('[email protected]')).toBe('[email protected]');
+    });
+
+    it('returns anything that is not an address unchanged', () => {
+        expect(clean('not-an-email')).toBe('not-an-email');
+        expect(clean('@nolocal.test')).toBe('@nolocal.test');
+    });
+});
+
+describe('EmailClient.validate', () => {
+    it('waves everything through in a dev environment', async () => {
+        const client = startClient({ env: 'dev' } as Partial<IConfig>);
+        await expect(client.validate('[email protected]')).resolves.toBe(
+            true,
+        );
+    });
+
+    it('rejects a blocked domain suffix', async () => {
+        const client = startClient({
+            blockedEmailDomains: ['blocked.test'],
+        } as unknown as Partial<IConfig>);
+
+        await expect(client.validate('[email protected]')).resolves.toBe(
+            false,
+        );
+        await expect(client.validate('[email protected]')).resolves.toBe(
+            true,
+        );
+    });
+
+    it('matches the blocklist against the cleaned address', async () => {
+        const client = startClient({
+            blockedEmailDomains: ['@gmail.com'],
+        } as unknown as Partial<IConfig>);
+        await expect(
+            client.validate('[email protected]'),
+        ).resolves.toBe(false);
+    });
+
+    it('lets a registered validator veto an address', async () => {
+        const client = startClient();
+        const seen: string[] = [];
+        client.addValidator((email) => {
+            seen.push(email);
+            return !email.startsWith('spam');
+        });
+
+        await expect(client.validate('[email protected]')).resolves.toBe(
+            false,
+        );
+        await expect(client.validate('[email protected]')).resolves.toBe(true);
+        // Validators always see the canonical form.
+        expect(seen).toEqual(['[email protected]', '[email protected]']);
+    });
+
+    it('supports asynchronous validators', async () => {
+        const client = startClient();
+        client.addValidator(async (email) => email !== '[email protected]');
+        await expect(client.validate('[email protected]')).resolves.toBe(false);
+        await expect(client.validate('[email protected]')).resolves.toBe(true);
+    });
+});

src/backend/clients/email/EmailClient.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -110,10 +110,11 @@ const DOMAIN_ALIASES: Record<string, string> = {
 
 /**
  * Unified email client. Handles:
- *   - Template-based outbound mail (via `send`)
- *   - Raw nodemailer passthrough (via `sendRaw`)
- *   - Canonical-form normalization for dedup (via `clean`)
- *   - Policy + extensible validation (via `validate`)
+ *
+ * - Template-based outbound mail (via `send`)
+ * - Raw nodemailer passthrough (via `sendRaw`)
+ * - Canonical-form normalization for dedup (via `clean`)
+ * - Policy + extensible validation (via `validate`)
  */
 export class EmailClient extends PuterClient {
     private transport: ReturnType<typeof nodemailer.createTransport> | null =
@@ -151,9 +152,7 @@ export class EmailClient extends PuterClient {
 
     // -- Public API: sending ------------------------------------------
 
-    /**
-     * Render a template and send it to `to`.
-     */
+    /** Render a template and send it to `to`. */
     async send<T extends EmailTemplateName>(
         to: string,
         template: T,
@@ -173,12 +172,12 @@ export class EmailClient extends PuterClient {
     }
 
     /**
-     * Raw send — bypasses the template system. Useful for one-off
-     * admin emails that don't warrant a named template.
+     * Raw send — bypasses the template system. Useful for one-off admin emails
+     * that don't warrant a named template.
      *
-     * Returns the transport's send result, or `null` when no transport
-     * is configured (the send is a no-op in that case — callers that
-     * must not silently drop mail should check `isConfigured` first).
+     * Returns the transport's send result, or `null` when no transport is
+     * configured (the send is a no-op in that case — callers that must not
+     * silently drop mail should check `isConfigured` first).
      */
     async sendRaw(options: SendMailOptions) {
         if (!this.transport) {
@@ -202,9 +201,9 @@ export class EmailClient extends PuterClient {
     // -- Public API: clean / validate ---------------------------------
 
     /**
-     * Normalize an email to its canonical form for dedup comparisons.
-     * Applies provider-specific rules (e.g. Gmail ignores dots in
-     * the local part) plus generic subaddressing removal.
+     * Normalize an email to its canonical form for dedup comparisons. Applies
+     * provider-specific rules (e.g. Gmail ignores dots in the local part) plus
+     * generic subaddressing removal.
      */
     clean(email: string): string {
         let [local, domain] = email.split('@');
@@ -233,9 +232,9 @@ export class EmailClient extends PuterClient {
     }
 
     /**
-     * Check whether an email is allowed to be used. Checks domain
-     * blocklist plus any registered validators (services can call
-     * `addValidator()` to register custom policy hooks).
+     * Check whether an email is allowed to be used. Checks domain blocklist
+     * plus any registered validators (services can call `addValidator()` to
+     * register custom policy hooks).
      */
     async validate(email: string): Promise<boolean> {
         if (this.config.env === 'dev') return true;
@@ -258,9 +257,8 @@ export class EmailClient extends PuterClient {
     }
 
     /**
-     * Register a custom validation hook. Services can call this
-     * during their startup to veto specific emails (e.g. a
-     * disposable-email service).
+     * Register a custom validation hook. Services can call this during their
+     * startup to veto specific emails (e.g. a disposable-email service).
      */
     addValidator(fn: EmailValidator): void {
         this.validators.push(fn);

src/backend/clients/email/templates.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -18,12 +18,12 @@
  */
 
 /**
- * Email template definitions. Keys are the template names; values are
- * the Handlebars-compilable `subject` and `html` strings.
+ * Email template definitions. Keys are the template names; values are the
+ * Handlebars-compilable `subject` and `html` strings.
  *
- * Rendered values are supplied by callers of `EmailClient.send()`.
- * Variables use standard Handlebars syntax: `{{var}}`, `{{#if cond}}…{{/if}}`,
- * and the custom helper `{{{nl2br text}}}` for HTML-safe newline conversion.
+ * Rendered values are supplied by callers of `EmailClient.send()`. Variables
+ * use standard Handlebars syntax: `{{var}}`, `{{#if cond}}…{{/if}}`, and the
+ * custom helper `{{{nl2br text}}}` for HTML-safe newline conversion.
  */
 
 export interface EmailTemplate {

src/backend/clients/event/EventClient.test.ts

@@ -1,5 +1,6 @@
 import {
     afterAll,
+    afterEach,
     beforeAll,
     beforeEach,
     describe,
@@ -7,6 +8,7 @@ import {
     it,
     vi,
 } from 'vitest';
+import { extensionStore } from '../../extensions.ts';
 import { PuterServer } from '../../server.ts';
 import { setupTestServer } from '../../testUtil.ts';
 import type { EventClient } from './EventClient.js';
@@ -21,12 +23,11 @@ describe('EventClient', () => {
     });
 
     afterAll(async () => {
-        await server.shutdown();
+        await server?.shutdown();
     });
 
     // Each test gets a fresh key so listeners registered by earlier tests
-    // never collide with later ones (the client has no public way to
-    // unsubscribe).
+    // never collide with later ones.
     let key: string;
     beforeEach(() => {
         key = `test.${Math.random().toString(36).slice(2)}`;
@@ -184,6 +185,74 @@ describe('EventClient', () => {
         });
     });
 
+    describe('off', () => {
+        it('stops delivering to a removed listener', () => {
+            const kept = vi.fn();
+            const removed = vi.fn();
+            target.on(key, kept);
+            target.on(key, removed);
+
+            target.off(key, removed);
+            target.emit(key, {}, {});
+
+            expect(kept).toHaveBeenCalledTimes(1);
+            expect(removed).not.toHaveBeenCalled();
+        });
+
+        it('ignores a key nobody ever subscribed to', () => {
+            expect(() => target.off(key, vi.fn())).not.toThrow();
+        });
+
+        it('leaves the list alone when the listener was never registered', () => {
+            const listener = vi.fn();
+            target.on(key, listener);
+
+            target.off(key, vi.fn());
+            target.emit(key, {}, {});
+
+            expect(listener).toHaveBeenCalledTimes(1);
+        });
+    });
+
+    describe('extension-registered listeners', () => {
+        afterEach(() => {
+            delete extensionStore.events[key];
+        });
+
+        it('fires alongside listeners registered on the client', () => {
+            const fromExtension = vi.fn();
+            const fromClient = vi.fn();
+            extensionStore.events[key] = [fromExtension];
+            target.on(key, fromClient);
+
+            target.emit(key, { n: 1 }, { source: 'test' });
+
+            expect(fromExtension).toHaveBeenCalledWith(
+                key,
+                { n: 1 },
+                { source: 'test' },
+            );
+            expect(fromClient).toHaveBeenCalledTimes(1);
+        });
+
+        it('is awaited by emitAndWait', async () => {
+            const order: string[] = [];
+            extensionStore.events[key] = [
+                async () => {
+                    await new Promise((resolve) => setTimeout(resolve, 5));
+                    order.push('extension');
+                },
+            ];
+            target.on(key, () => {
+                order.push('client');
+            });
+
+            await target.emitAndWait(key, {}, {});
+
+            expect(order).toEqual(['client', 'extension']);
+        });
+    });
+
     describe('lifecycle hooks', () => {
         it('onServerStart emits a serverStart event', () => {
             const listener = vi.fn();

src/backend/clients/event/EventClient.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -44,20 +44,19 @@ export class EventClient extends PuterClient {
     /**
      * Dispatch an event to every matching subscriber.
      *
-     * Match semantics: emit walks every dot-separated prefix of `key`,
-     * looking up `<prefix>.*` listeners for prefixes shorter than the full
-     * key, and exact-key listeners on the final iteration. So emitting
+     * Match semantics: emit walks every dot-separated prefix of `key`, looking
+     * up `<prefix>.*` listeners for prefixes shorter than the full key, and
+     * exact-key listeners on the final iteration. So emitting
      * `outer.gui.item.removed` fires subscribers on:
      *
-     *   - `outer.*`
-     *   - `outer.gui.*`
-     *   - `outer.gui.item.*`
-     *   - `outer.gui.item.removed`
-     *
-     * Subscribers are still keyed in a single map — wildcards just live
-     * under their literal `<prefix>.*` string. No regex, no per-emit
-     * scan of every listener.
+     * - `outer.*`
+     * - `outer.gui.*`
+     * - `outer.gui.item.*`
+     * - `outer.gui.item.removed`
      *
+     * Subscribers are still keyed in a single map — wildcards just live under
+     * their literal `<prefix>.*` string. No regex, no per-emit scan of every
+     * listener.
      */
     emit<T extends keyof EventMap>(
         key: T,
@@ -85,15 +84,15 @@ export class EventClient extends PuterClient {
     /**
      * Like `emit`, but awaits every matched listener before resolving.
      *
-     * Use this when the emitter needs to act on mutations the handlers made
-     * to `data` — e.g. validation hooks where a listener can set
-     * `data.allow = false` to reject, or pre-commit pipelines where every
-     * stage must complete before the next step runs. Regular `emit` is
-     * fire-and-forget and can't observe handler state changes.
+     * Use this when the emitter needs to act on mutations the handlers made to
+     * `data` — e.g. validation hooks where a listener can set `data.allow =
+     * false` to reject, or pre-commit pipelines where every stage must complete
+     * before the next step runs. Regular `emit` is fire-and-forget and can't
+     * observe handler state changes.
      *
-     * Listeners run sequentially in the order they're registered so an
-     * earlier handler's mutation is visible to later ones. A listener that
-     * throws is logged (same as `emit`) and the chain continues.
+     * Listeners run sequentially in the order they're registered so an earlier
+     * handler's mutation is visible to later ones. A listener that throws is
+     * logged (same as `emit`) and the chain continues.
      */
     async emitAndWait<T extends keyof EventMap>(
         key: T,
@@ -133,15 +132,13 @@ export class EventClient extends PuterClient {
     /**
      * Subscribe to an event by exact key OR a wildcard prefix.
      *
-     * Wildcards: a key ending in `.*` matches every event whose name
-     * starts with the prefix. `outer.*` matches `outer.gui.item.removed`,
-     * `outer.fs.write-hash`, and any other dot-extended descendant.
-     * Exact keys still match exactly. See `emit()` for the dispatch order.
-     *
-     * Callback receives the full `(key, data, meta)` tuple as passed
-     * to `emit()` — wildcard subscribers can branch on the triggering
-     * event name.
+     * Wildcards: a key ending in `.*` matches every event whose name starts
+     * with the prefix. `outer.*` matches `outer.gui.item.removed`,
+     * `outer.fs.write-hash`, and any other dot-extended descendant. Exact keys
+     * still match exactly. See `emit()` for the dispatch order.
      *
+     * Callback receives the full `(key, data, meta)` tuple as passed to
+     * `emit()` — wildcard subscribers can branch on the triggering event name.
      */
     on<P extends ListenKey>(
         key: P,

src/backend/clients/index.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.

src/backend/clients/prelude/PreludeClient.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -74,11 +74,11 @@ export type PreludeCheckStatus =
     | 'transaction_mismatch';
 
 /**
- * Prelude Verify v2 client (https://docs.prelude.so/verify/v2). Sends and checks
- * SMS one-time codes — Prelude generates, delivers, and validates the code, so
- * we never store one ourselves. No-ops with a warning when no API key is
- * configured (so dev environments don't crash); `isConfigured()` lets callers
- * surface a clean "phone verification unavailable" error instead.
+ * Prelude Verify v2 client (https://docs.prelude.so/verify/v2). Sends and
+ * checks SMS one-time codes — Prelude generates, delivers, and validates the
+ * code, so we never store one ourselves. No-ops with a warning when no API key
+ * is configured (so dev environments don't crash); `isConfigured()` lets
+ * callers surface a clean "phone verification unavailable" error instead.
  */
 export class PreludeClient extends PuterClient {
     private apiKey: string | null = null;
@@ -113,7 +113,9 @@ export class PreludeClient extends PuterClient {
 
     /**
      * Whether SMS verification should be offered for a country. False when the
-     * country is unknown, has no SMS channel, or its rate exceeds the cost cap.
+     * country is unknown, has no SMS channel, or its rate exceeds the cost
+     * cap.
+     *
      * @param iso ISO-3166 alpha-2 (e.g. 'US') — from the parsed phone number.
      */
     isCountrySupported(iso: string | undefined): boolean {
@@ -174,7 +176,9 @@ export class PreludeClient extends PuterClient {
     }
 
     /**
-     * Check a code the user entered against the active verification for `target`.
+     * Check a code the user entered against the active verification for
+     * `target`.
+     *
      * @returns `{ status }` — `'success'` means verified.
      */
     async checkVerification(

src/backend/clients/prelude/countries.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -17,11 +17,13 @@
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
-/** Per-country Prelude SMS pricing, hardcoded from the Prelude global price
+/**
+ * Per-country Prelude SMS pricing, hardcoded from the Prelude global price
  * sheet. `sms` is the average cost in EUR, or null when SMS is unavailable
  * there. Used to cap phone verification to affordable countries (see
  * PreludeClient.isCountrySupported). Regenerate from the price sheet when
- * Prelude updates rates. */
+ * Prelude updates rates.
+ */
 export interface CountryPrice {
     name: string;
     /** Prelude SMS average in EUR, or null when SMS is not available. */

src/backend/clients/redis/RedisClient.test.ts

@@ -0,0 +1,171 @@
+/**
+ * Copyright (C) 2024-present Puter Technologies Inc.
+ *
+ * This file is part of Puter.
+ *
+ * Puter is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+import { afterEach, describe, expect, it, vi } from 'vitest';
+import type { IConfig } from '../../types';
+import { RedisClient } from './RedisClient';
+
+const config = (redis: Record<string, unknown>): IConfig =>
+    ({ port: 0, extensions: [], redis }) as unknown as IConfig;
+
+type ClusterOptions = {
+    redisOptions?: { tls?: unknown; connectTimeout?: number };
+    clusterRetryStrategy?: (attempts: number) => number;
+};
+
+const optionsOf = (client: RedisClient): ClusterOptions =>
+    (client as unknown as { options: ClusterOptions }).options;
+
+describe('RedisClient — in-process mock', () => {
+    let client: RedisClient | null = null;
+
+    afterEach(async () => {
+        if (client) await client.onServerShutdown();
+        client = null;
+    });
+
+    it('falls back to the mock when no startup nodes are configured', async () => {
+        client = new RedisClient(config({}));
+        await client.set('greeting', 'hello');
+        await expect(client.get('greeting')).resolves.toBe('hello');
+    });
+
+    it('honours an explicit mock request even with startup nodes present', async () => {
+        client = new RedisClient(
+            config({
+                useMock: true,
+                startupNodes: [{ host: 'redis.internal', port: 6379 }],
+            }),
+        );
+        await client.set('k', 'v');
+        await expect(client.get('k')).resolves.toBe('v');
+    });
+
+    it('exposes the shutdown hook directly on the cluster instance', () => {
+        client = new RedisClient(config({}));
+        expect(typeof client.onServerShutdown).toBe('function');
+    });
+
+    it('disconnects when a clean quit fails', async () => {
+        const instance = new RedisClient(config({}));
+        const warn = vi.spyOn(console, 'warn').mockImplementation(() => {});
+        vi.spyOn(instance, 'quit').mockRejectedValue(new Error('quit refused'));
+        const disconnect = vi.spyOn(instance, 'disconnect');
+
+        await instance.onServerShutdown();
+
+        expect(disconnect).toHaveBeenCalledTimes(1);
+        expect(warn).toHaveBeenCalledWith(
+            '[redis] failed to quit redis client cleanly',
+            expect.any(Error),
+        );
+        warn.mockRestore();
+    });
+});
+
+describe('RedisClient — real cluster wiring', () => {
+    let client: RedisClient | null = null;
+
+    afterEach(() => {
+        client?.disconnect();
+        client = null;
+    });
+
+    const startupNodes = [{ host: '127.0.0.1', port: 7001 }];
+
+    it('enables TLS by default and bounds the connect timeout', () => {
+        client = new RedisClient(config({ startupNodes }));
+        expect(optionsOf(client).redisOptions?.tls).toEqual({});
+        expect(optionsOf(client).redisOptions?.connectTimeout).toBe(10000);
+    });
+
+    it('lets a plain-TCP deployment opt out of TLS', () => {
+        client = new RedisClient(config({ startupNodes, tls: false }));
+        expect(optionsOf(client).redisOptions?.tls).toBeUndefined();
+    });
+
+    it('backs off on cluster retries up to a ceiling', () => {
+        client = new RedisClient(config({ startupNodes, tls: false }));
+        const retry = optionsOf(client).clusterRetryStrategy!;
+        expect(retry(0)).toBe(100);
+        expect(retry(5)).toBe(600);
+        expect(retry(100)).toBe(2000);
+    });
+
+    it('treats startup churn as a warning and everything else as an error', () => {
+        const warn = vi.spyOn(console, 'warn').mockImplementation(() => {});
+        const error = vi.spyOn(console, 'error').mockImplementation(() => {});
+        client = new RedisClient(config({ startupNodes, tls: false }));
+
+        client.emit('error', new Error('None of startup nodes is available'));
+        expect(warn).toHaveBeenCalledWith(
+            expect.stringContaining('startup issue while connecting'),
+        );
+
+        const fatal = new Error('WRONGPASS invalid credentials');
+        client.emit('error', fatal);
+        expect(error).toHaveBeenCalledWith('[redis] cluster error', fatal);
+
+        warn.mockRestore();
+        error.mockRestore();
+    });
+
+    it('applies the same triage to per-node errors', () => {
+        const warn = vi.spyOn(console, 'warn').mockImplementation(() => {});
+        const error = vi.spyOn(console, 'error').mockImplementation(() => {});
+        client = new RedisClient(config({ startupNodes, tls: false }));
+
+        const transient = new Error('boom');
+        transient.name = 'ClusterAllFailedError';
+        client.emit('node error', transient, '127.0.0.1:7001');
+        expect(warn).toHaveBeenCalledWith(
+            expect.stringContaining(
+                'startup issue for cluster node 127.0.0.1:7001',
+            ),
+        );
+
+        const fatal = new Error('node exploded');
+        client.emit('node error', fatal, '127.0.0.1:7002');
+        expect(error).toHaveBeenCalledWith(
+            '[redis] cluster node error (127.0.0.1:7002)',
+            fatal,
+        );
+
+        // Non-Error payloads are stringified rather than crashing the handler.
+        client.emit('node error', 'None of startup nodes is available', 'n3');
+        expect(warn).toHaveBeenCalledWith(
+            expect.stringContaining('startup issue for cluster node n3'),
+        );
+
+        warn.mockRestore();
+        error.mockRestore();
+    });
+
+    it('logs the transport lifecycle once each', () => {
+        const log = vi.spyOn(console, 'log').mockImplementation(() => {});
+        client = new RedisClient(config({ startupNodes, tls: false }));
+
+        client.emit('connect');
+        client.emit('ready');
+
+        expect(log).toHaveBeenCalledWith('[redis] cluster transport connected');
+        expect(log).toHaveBeenCalledWith('[redis] cluster ready');
+        log.mockRestore();
+    });
+});

src/backend/clients/redis/RedisClient.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -108,13 +108,13 @@ const buildCluster = (config: IConfig): Cluster => {
 
 /**
  * `RedisClient` IS the ioredis `Cluster` instance — consumers call
- * `this.clients.redis.get(...)` / `.set(...)` directly rather than
- * going through an inner `.client` field. Lifecycle methods
- * (`onServerShutdown`) are attached onto the cluster instance itself.
+ * `this.clients.redis.get(...)` / `.set(...)` directly rather than going
+ * through an inner `.client` field. Lifecycle methods (`onServerShutdown`) are
+ * attached onto the cluster instance itself.
  *
- * Type-wise, `RedisClient` is `Cluster & WithLifecycle`; the registry-
- * facing value below is a constructor that returns that shape. Mirrors
- * the `DatabaseClientFactory` pattern.
+ * Type-wise, `RedisClient` is `Cluster & WithLifecycle`; the registry- facing
+ * value below is a constructor that returns that shape. Mirrors the
+ * `DatabaseClientFactory` pattern.
  */
 export type RedisClient = Cluster & WithLifecycle;
 

src/backend/clients/s3/S3Client.test.ts

@@ -0,0 +1,489 @@
+/**
+ * Copyright (C) 2024-present Puter Technologies Inc.
+ *
+ * This file is part of Puter.
+ *
+ * Puter is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+import { GetObjectCommand } from '@aws-sdk/client-s3';
+import { mkdirSync, mkdtempSync, rmSync, writeFileSync } from 'node:fs';
+import { existsSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
+import type { IConfig } from '../../types';
+import { S3Client } from './S3Client';
+
+const LOCAL_BUCKET = 'puter-local';
+
+/**
+ * The multipart helper takes its command sender as a parameter, so the failure
+ * paths can be driven without a live endpoint.
+ */
+type S3Internals = {
+    awsConfig: { endpoint?: string };
+    migrateLegacyStorage(opts?: {
+        bucket?: string;
+        legacyPath?: string;
+    }): Promise<{ migratedFileCount: number; scannedEntryCount: number }>;
+    uploadMultipart(args: {
+        bucket: string;
+        client: { send: (command: unknown) => Promise<unknown> };
+        filePath: string;
+        fileSize: number;
+        key: string;
+    }): Promise<void>;
+};
+
+const internals = (client: S3Client) => client as unknown as S3Internals;
+
+const localConfig = (): IConfig =>
+    ({
+        port: 0,
+        extensions: [],
+        s3: { localConfig: { inMemory: true } },
+    }) as unknown as IConfig;
+
+const startLocal = async (): Promise<S3Client> => {
+    const client = new S3Client(localConfig());
+    await client.onServerStart();
+    return client;
+};
+
+const objectBody = async (
+    client: S3Client,
+    key: string,
+): Promise<string | undefined> => {
+    const result = await client
+        .get()
+        .send(new GetObjectCommand({ Bucket: LOCAL_BUCKET, Key: key }));
+    return result.Body?.transformToString();
+};
+
+describe('S3Client — local development endpoint', () => {
+    let client: S3Client;
+
+    beforeEach(async () => {
+        client = await startLocal();
+    });
+
+    afterEach(async () => {
+        await client.onServerShutdown();
+    });
+
+    it('points clients at the in-process object store', async () => {
+        await client
+            .get()
+            .send(
+                new GetObjectCommand({
+                    Bucket: LOCAL_BUCKET,
+                    Key: 'definitely-absent',
+                }),
+            )
+            .then(
+                () => {
+                    throw new Error('expected a missing-key failure');
+                },
+                (error: { name?: string }) => {
+                    expect(error.name).toBe('NoSuchKey');
+                },
+            );
+    });
+
+    it('reuses one client per region and mints a new one per region', () => {
+        const first = client.get('us-west-2');
+        expect(client.get('us-west-2')).toBe(first);
+        expect(client.get('eu-central-1')).not.toBe(first);
+    });
+
+    it('serves presigning from the same client when no public endpoint is set', () => {
+        expect(client.getForPresign('us-west-2')).toBe(client.get('us-west-2'));
+    });
+
+    it('keeps modest upload thresholds so the local store is not overwhelmed', () => {
+        expect(client.maxSingleUploadSize).toBe(10 * 1024 * 1024);
+        expect(client.partSize).toBe(5 * 1024 * 1024);
+    });
+});
+
+describe('S3Client — remote endpoint configuration', () => {
+    let local: S3Client;
+    let remote: S3Client | null = null;
+
+    beforeEach(async () => {
+        local = await startLocal();
+    });
+
+    afterEach(async () => {
+        if (remote) await remote.onServerShutdown();
+        remote = null;
+        await local.onServerShutdown();
+    });
+
+    const remoteConfig = (extra: Record<string, unknown>): IConfig =>
+        ({
+            port: 0,
+            extensions: [],
+            s3: {
+                s3Config: {
+                    endpoint: internals(local).awsConfig.endpoint,
+                    accessKeyId: 'fakeAccessKeyId',
+                    secretAccessKey: 'fakeSecretAccessKey',
+                    region: 'us-west-2',
+                    forcePathStyle: true,
+                    ...extra,
+                },
+            },
+        }) as unknown as IConfig;
+
+    it('talks to a configured S3-compatible endpoint', async () => {
+        remote = new S3Client(remoteConfig({}));
+        await remote.onServerStart();
+
+        await remote
+            .get()
+            .send(new GetObjectCommand({ Bucket: LOCAL_BUCKET, Key: 'nope' }))
+            .then(
+                () => {
+                    throw new Error('expected a missing-key failure');
+                },
+                (error: { name?: string }) => {
+                    expect(error.name).toBe('NoSuchKey');
+                },
+            );
+    });
+
+    it('signs browser-facing URLs against the public endpoint', async () => {
+        remote = new S3Client(
+            remoteConfig({ publicEndpoint: 'https://cdn.example.test' }),
+        );
+        await remote.onServerStart();
+
+        const presign = remote.getForPresign('us-west-2');
+        expect(presign).not.toBe(remote.get('us-west-2'));
+        // Cached per region like the regular client map.
+        expect(remote.getForPresign('us-west-2')).toBe(presign);
+        expect(remote.getForPresign('eu-central-1')).not.toBe(presign);
+    });
+
+    it('shares one client when the public endpoint matches the private one', async () => {
+        const endpoint = internals(local).awsConfig.endpoint;
+        remote = new S3Client(remoteConfig({ publicEndpoint: endpoint }));
+        await remote.onServerStart();
+
+        expect(remote.getForPresign('us-west-2')).toBe(remote.get('us-west-2'));
+    });
+
+    it('raises the upload thresholds when using the ambient credential chain', async () => {
+        remote = new S3Client({
+            port: 0,
+            extensions: [],
+            s3: { s3Config: { useCredentialChain: true } },
+        } as unknown as IConfig);
+        await remote.onServerStart();
+
+        expect(remote.partSize).toBe(64 * 1024 * 1024);
+        expect(remote.maxSingleUploadSize).toBe(128 * 1024 * 1024);
+    });
+});
+
+describe('S3Client — legacy storage migration', () => {
+    let client: S3Client;
+    let dir: string;
+
+    beforeEach(async () => {
+        client = await startLocal();
+        dir = mkdtempSync(join(tmpdir(), 'puter-s3-legacy-'));
+    });
+
+    afterEach(async () => {
+        rmSync(dir, { recursive: true, force: true });
+        await client.onServerShutdown();
+    });
+
+    it('does nothing when there is no legacy directory', async () => {
+        await expect(
+            internals(client).migrateLegacyStorage({
+                legacyPath: join(dir, 'absent'),
+            }),
+        ).resolves.toEqual({ migratedFileCount: 0, scannedEntryCount: 0 });
+    });
+
+    it('uploads each legacy file, skips directories, then removes the tree', async () => {
+        const small = 'small-file-contents';
+        writeFileSync(join(dir, 'small.txt'), small);
+        writeFileSync(join(dir, 'other.txt'), 'other');
+        mkdirSync(join(dir, 'a-subdirectory'));
+
+        await expect(
+            internals(client).migrateLegacyStorage({ legacyPath: dir }),
+        ).resolves.toEqual({ migratedFileCount: 2, scannedEntryCount: 3 });
+
+        await expect(objectBody(client, 'small.txt')).resolves.toBe(small);
+        await expect(objectBody(client, 'other.txt')).resolves.toBe('other');
+        expect(existsSync(dir)).toBe(false);
+    });
+
+    it('switches to a multipart upload for a file over the single-put limit', async () => {
+        // S3 requires every part but the last to be at least 5 MiB, so the
+        // fixture has to straddle that for real.
+        client.maxSingleUploadSize = 1024 * 1024;
+        client.partSize = 5 * 1024 * 1024;
+        const body = 'X'.repeat(6 * 1024 * 1024);
+        writeFileSync(join(dir, 'large.bin'), body);
+
+        await expect(
+            internals(client).migrateLegacyStorage({ legacyPath: dir }),
+        ).resolves.toEqual({ migratedFileCount: 1, scannedEntryCount: 1 });
+        await expect(objectBody(client, 'large.bin')).resolves.toBe(body);
+    });
+});
+
+describe('S3Client — multipart failure handling', () => {
+    let client: S3Client;
+    let dir: string;
+    let filePath: string;
+
+    beforeEach(async () => {
+        client = await startLocal();
+        dir = mkdtempSync(join(tmpdir(), 'puter-s3-multipart-'));
+        filePath = join(dir, 'part-source.bin');
+        writeFileSync(filePath, 'Y'.repeat(30));
+        client.partSize = 10;
+    });
+
+    afterEach(async () => {
+        rmSync(dir, { recursive: true, force: true });
+        await client.onServerShutdown();
+    });
+
+    const commandName = (command: unknown) =>
+        (command as { constructor: { name: string } }).constructor.name;
+
+    it('fails when the store will not open a multipart upload', async () => {
+        const send = vi.fn(async () => ({}));
+
+        await expect(
+            internals(client).uploadMultipart({
+                bucket: LOCAL_BUCKET,
+                client: { send },
+                filePath,
+                fileSize: 30,
+                key: 'no-upload-id',
+            }),
+        ).rejects.toThrow('Failed to start multipart upload');
+    });
+
+    it('aborts the upload when a part comes back without an ETag', async () => {
+        const sent: string[] = [];
+        const send = vi.fn(async (command: unknown) => {
+            const name = commandName(command);
+            sent.push(name);
+            if (name === 'CreateMultipartUploadCommand') {
+                return { UploadId: 'upload-1' };
+            }
+            if (name === 'UploadPartCommand') return {};
+            return {};
+        });
+
+        await expect(
+            internals(client).uploadMultipart({
+                bucket: LOCAL_BUCKET,
+                client: { send },
+                filePath,
+                fileSize: 30,
+                key: 'etag-less',
+            }),
+        ).rejects.toMatchObject({ statusCode: 400, legacyCode: 'bad_request' });
+
+        expect(sent).toEqual([
+            'CreateMultipartUploadCommand',
+            'UploadPartCommand',
+            'AbortMultipartUploadCommand',
+        ]);
+    });
+
+    it('sends one part per chunk and completes with every ETag', async () => {
+        const parts: { PartNumber: number; ContentLength: number }[] = [];
+        let completed: { ETag: string; PartNumber: number }[] | undefined;
+        const send = vi.fn(async (command: unknown) => {
+            const name = commandName(command);
+            const input = (command as { input: Record<string, unknown> }).input;
+            if (name === 'CreateMultipartUploadCommand') {
+                return { UploadId: 'upload-1' };
+            }
+            if (name === 'UploadPartCommand') {
+                parts.push({
+                    PartNumber: input.PartNumber as number,
+                    ContentLength: input.ContentLength as number,
+                });
+                return { ETag: `etag-${input.PartNumber}` };
+            }
+            if (name === 'CompleteMultipartUploadCommand') {
+                completed = (
+                    input.MultipartUpload as {
+                        Parts: { ETag: string; PartNumber: number }[];
+                    }
+                ).Parts;
+            }
+            return {};
+        });
+
+        client.partSize = 12;
+        await internals(client).uploadMultipart({
+            bucket: LOCAL_BUCKET,
+            client: { send },
+            filePath,
+            fileSize: 30,
+            key: 'chunked',
+        });
+
+        expect(parts).toEqual([
+            { PartNumber: 1, ContentLength: 12 },
+            { PartNumber: 2, ContentLength: 12 },
+            { PartNumber: 3, ContentLength: 6 },
+        ]);
+        expect(completed).toEqual([
+            { ETag: 'etag-1', PartNumber: 1 },
+            { ETag: 'etag-2', PartNumber: 2 },
+            { ETag: 'etag-3', PartNumber: 3 },
+        ]);
+    });
+
+    it('aborts and rethrows when completing the upload fails', async () => {
+        const sent: string[] = [];
+        const send = vi.fn(async (command: unknown) => {
+            const name = commandName(command);
+            sent.push(name);
+            if (name === 'CreateMultipartUploadCommand') {
+                return { UploadId: 'upload-1' };
+            }
+            if (name === 'UploadPartCommand') return { ETag: 'etag' };
+            if (name === 'CompleteMultipartUploadCommand') {
+                throw new Error('complete rejected');
+            }
+            return {};
+        });
+
+        await expect(
+            internals(client).uploadMultipart({
+                bucket: LOCAL_BUCKET,
+                client: { send },
+                filePath,
+                fileSize: 30,
+                key: 'incomplete',
+            }),
+        ).rejects.toThrow('complete rejected');
+
+        expect(sent.at(-1)).toBe('AbortMultipartUploadCommand');
+    });
+});
+
+describe('S3Client — disk-backed local store', () => {
+    let cwd: string;
+    let dir: string;
+    let client: S3Client | null = null;
+
+    beforeEach(() => {
+        cwd = process.cwd();
+        dir = mkdtempSync(join(tmpdir(), 'puter-s3-disk-'));
+    });
+
+    afterEach(async () => {
+        if (client) await client.onServerShutdown();
+        client = null;
+        process.chdir(cwd);
+        rmSync(dir, { recursive: true, force: true });
+    });
+
+    it('persists to the configured directories and drains legacy storage', async () => {
+        // The legacy sweep resolves `storage/` against the working
+        // directory, so the whole fixture lives in a throwaway cwd.
+        process.chdir(dir);
+        mkdirSync(join(dir, 'storage'));
+        writeFileSync(join(dir, 'storage', 'legacy.txt'), 'from-disk');
+
+        const log = vi.spyOn(console, 'log').mockImplementation(() => {});
+        client = new S3Client({
+            port: 0,
+            extensions: [],
+            s3: {
+                localConfig: {
+                    host: '127.0.0.1',
+                    port: 0,
+                    dataDir: join(dir, 'fauxqs-data'),
+                    s3StorageDir: join(dir, 'fauxqs-s3'),
+                },
+            },
+        } as unknown as IConfig);
+        await client.onServerStart();
+
+        expect(log).toHaveBeenCalledWith(
+            '[s3] migrated 1 file(s) from legacy storage',
+        );
+        await expect(objectBody(client, 'legacy.txt')).resolves.toBe(
+            'from-disk',
+        );
+        expect(existsSync(join(dir, 'storage'))).toBe(false);
+        log.mockRestore();
+    });
+});
+
+describe('S3Client — short reads during multipart', () => {
+    let client: S3Client;
+    let dir: string;
+
+    beforeEach(async () => {
+        client = await startLocal();
+        dir = mkdtempSync(join(tmpdir(), 'puter-s3-short-'));
+    });
+
+    afterEach(async () => {
+        rmSync(dir, { recursive: true, force: true });
+        await client.onServerShutdown();
+    });
+
+    it('stops uploading parts once the file runs out early', async () => {
+        const filePath = join(dir, 'truncated.bin');
+        writeFileSync(filePath, 'Z'.repeat(20));
+        client.partSize = 10;
+
+        const parts: number[] = [];
+        const send = vi.fn(async (command: unknown) => {
+            const name = (command as { constructor: { name: string } })
+                .constructor.name;
+            const input = (command as { input: Record<string, unknown> }).input;
+            if (name === 'CreateMultipartUploadCommand') {
+                return { UploadId: 'upload-1' };
+            }
+            if (name === 'UploadPartCommand') {
+                parts.push(input.ContentLength as number);
+                return { ETag: `etag-${input.PartNumber}` };
+            }
+            return {};
+        });
+
+        // The caller's size is stale — the file is shorter than advertised.
+        await internals(client).uploadMultipart({
+            bucket: LOCAL_BUCKET,
+            client: { send },
+            filePath,
+            fileSize: 50,
+            key: 'truncated',
+        });
+
+        expect(parts).toEqual([10, 10]);
+    });
+});

src/backend/clients/s3/S3Client.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -184,8 +184,8 @@ export class S3Client extends PuterClient {
     // ------------------------------------------------------------------
 
     /**
-     * Get (or create) an S3Client for the given region.
-     * Clients are cached per-region for connection reuse.
+     * Get (or create) an S3Client for the given region. Clients are cached
+     * per-region for connection reuse.
      */
     get(
         region = this.config.s3_region || this.config.region || 'us-west-2',
@@ -213,10 +213,10 @@ export class S3Client extends PuterClient {
 
     /**
      * Client used to generate browser-facing presigned URLs. When
-     * `s3Config.publicEndpoint` is set, this returns a client bound to
-     * that endpoint — its signatures resolve against the public host
-     * the browser will actually hit. When unset, falls back to the
-     * regular client (prod behavior: one public endpoint everywhere).
+     * `s3Config.publicEndpoint` is set, this returns a client bound to that
+     * endpoint — its signatures resolve against the public host the browser
+     * will actually hit. When unset, falls back to the regular client (prod
+     * behavior: one public endpoint everywhere).
      */
     getForPresign(
         region = this.config.s3_region || this.config.region || 'us-west-2',

src/backend/clients/types.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -45,8 +45,8 @@ export interface IExtensionClientInstances {
     /**
      * Optional ClickHouse analytics client. Absent by default — a production
      * deployment registers it via an extension to speed up the app-stats path
-     * at scale (see {@link ClickhouseClient}). Always branch on its presence
-     * and fall back to SQL.
+     * at scale (see {@link ClickhouseClient}). Always branch on its presence and
+     * fall back to SQL.
      */
     clickhouse?: ClickhouseClient;
 }

src/backend/controllers/apps/AppController.js

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -31,15 +31,66 @@ import DEFAULT_APP_ICON from './default-app-icon.js';
 /**
  * REST endpoints for app management.
  *
- * Delegates to AppDriver for the actual CRUD + permission logic —
- * these routes are just thin shape adapters that translate REST
- * conventions into driver calls.
+ * Delegates to AppDriver for the actual CRUD + permission logic — these routes
+ * are just thin shape adapters that translate REST conventions into driver
+ * calls.
  */
 export class AppController extends PuterController {
     get appStore() {
         return this.stores.app;
     }
 
+    // In-flight background app-open writes. Tracked only so tests and
+    // shutdown can wait for them — the request path never does.
+    #pendingOpenWrites = new Set();
+
+    /**
+     * Record an app open. `app_opens` is analytics: it backs the recent-apps
+     * list and the open counters, and no response field is derived from it. The
+     * client posts this without awaiting and updates its own recent list
+     * optimistically, so holding a response open for a primary write only added
+     * latency to the launch that write is measuring.
+     *
+     * Failures are logged, never surfaced — a dropped stat must not turn into a
+     * failed app open.
+     *
+     * @param {string} appUid
+     * @param {number} userId
+     * @returns {Promise<void>} Settles when the write and event emit finish
+     */
+    #recordAppOpen(appUid, userId) {
+        const ts = Math.floor(Date.now() / 1000);
+        const work = (async () => {
+            try {
+                await this.clients.db.write(
+                    'INSERT INTO `app_opens` (`app_uid`, `user_id`, `ts`) VALUES (?, ?, ?)',
+                    [appUid, userId, ts],
+                );
+            } catch (e) {
+                console.warn('[rao] insert failed:', e);
+            }
+
+            try {
+                this.clients.event?.emitAndWait(
+                    'app.opened',
+                    { app_uid: appUid, user_id: userId, ts },
+                    {},
+                );
+            } catch {
+                // event emission best-effort
+            }
+        })();
+
+        this.#pendingOpenWrites.add(work);
+        work.finally(() => this.#pendingOpenWrites.delete(work));
+        return work;
+    }
+
+    /** Await every in-flight app-open write. */
+    async drainPendingAppOpens() {
+        await Promise.allSettled([...this.#pendingOpenWrites]);
+    }
+
     get appDriver() {
         // Drivers are wired into the shared driversContainers export by
         // PuterServer at boot. Controllers get them lazily via this getter
@@ -148,33 +199,10 @@ export class AppController extends PuterController {
                         legacyCode: 'not_found',
                     });
 
-                // Persist open record
-                try {
-                    await this.clients.db.write(
-                        'INSERT INTO `app_opens` (`app_uid`, `user_id`, `ts`) VALUES (?, ?, ?)',
-                        [
-                            app_uid,
-                            req.actor.user.id,
-                            Math.floor(Date.now() / 1000),
-                        ],
-                    );
-                } catch (e) {
-                    console.warn('[rao] insert failed:', e);
-                }
-
-                try {
-                    this.clients.event?.emitAndWait(
-                        'app.opened',
-                        {
-                            app_uid,
-                            user_id: req.actor.user.id,
-                            ts: Math.floor(Date.now() / 1000),
-                        },
-                        {},
-                    );
-                } catch {
-                    // event emission best-effort
-                }
+                // Validation and authorization are settled by this point, so
+                // the caller learns the outcome now and the stats write lands
+                // on its own. See `#recordAppOpen`.
+                this.#recordAppOpen(app_uid, req.actor.user.id);
 
                 res.json({});
             },
@@ -214,7 +242,13 @@ export class AppController extends PuterController {
                             source: 'appsRoute',
                             args: req.query ?? {},
                         });
-                        return { ...shaped, privateAccess };
+                        return {
+                            ...shaped,
+                            privateAccess:
+                                shaped.privateAccess?.hasAccess === false
+                                    ? shaped.privateAccess
+                                    : privateAccess,
+                        };
                     }),
                 );
 
@@ -437,7 +471,11 @@ export class AppController extends PuterController {
                 }
                 setIconSecurityHeaders(res);
                 res.set('Content-Type', mime);
-                res.set('Cache-Control', 'public, max-age=60');
+                // Same freshness as the redirect path above — this is the
+                // same resource, just served inline because no CDN file
+                // exists yet. A 60s TTL made every app launch re-fetch the
+                // icon over a connection the launch itself is competing for.
+                res.set('Cache-Control', 'public, max-age=900');
                 res.send(Buffer.from(icon.slice(commaIdx + 1), 'base64'));
 
                 // Trigger background generation so next request hits the CDN
@@ -468,6 +506,14 @@ export class AppController extends PuterController {
     }
 
     onServerStart() {}
-    onServerPrepareShutdown() {}
+    /**
+     * Let outstanding stats writes finish before the process goes away —
+     * otherwise a deploy silently drops every open recorded in the seconds
+     * before it.
+     */
+    async onServerPrepareShutdown() {
+        await this.drainPendingAppOpens();
+    }
+
     onServerShutdown() {}
 }

src/backend/controllers/apps/AppController.test.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -91,6 +91,11 @@ const uniqueName = (prefix: string) =>
 const uniqueIndexUrl = () =>
     `https://example-${Math.random().toString(36).slice(2, 10)}.test/`;
 
+// 1x1 transparent PNG. The `icon` write path validates the decoded payload,
+// not just the declared MIME, so icon fixtures must be real images.
+const MINIMAL_PNG_BASE64 =
+    'iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAQAAAC1HAwCAAAAC0lEQVR42mNkYAAAAAYAAjCB0C8AAAAASUVORK5CYII=';
+
 const createApp = async (
     actor: Actor,
     overrides: Record<string, unknown> = {},
@@ -285,12 +290,7 @@ describe('AppController POST /rao', () => {
         const { res } = makeRes();
         await expect(
             withActor(actor, () =>
-                callRoute(
-                    'post',
-                    '/rao',
-                    makeReq({ body: {}, actor }),
-                    res,
-                ),
+                callRoute('post', '/rao', makeReq({ body: {}, actor }), res),
             ),
         ).rejects.toMatchObject({ statusCode: 400 });
     });
@@ -328,6 +328,9 @@ describe('AppController POST /rao', () => {
         );
         expect(captured.body).toEqual({});
 
+        // The stats write is deliberately not awaited by the request.
+        await server.controllers.apps.drainPendingAppOpens();
+
         const rows = (await server.clients.db.read(
             'SELECT `app_uid`, `user_id` FROM `app_opens` WHERE `app_uid` = ? AND `user_id` = ?',
             [app.uid, owner.userId],
@@ -335,6 +338,74 @@ describe('AppController POST /rao', () => {
         expect(rows).toHaveLength(1);
     });
 
+    // `app_opens` is analytics: the response carries nothing derived from it
+    // and the client never awaits the post. Holding the response open for a
+    // primary write put that write's latency inside the app launch it was
+    // measuring, on a connection the launch was competing for.
+    it('responds without waiting for the stats write', async () => {
+        const owner = await makeUser();
+        const app = await createApp(owner.actor);
+
+        let releaseWrite = () => {};
+        const writeSpy = vi
+            .spyOn(server.clients.db, 'write')
+            .mockImplementation(
+                () =>
+                    new Promise((resolve) => {
+                        releaseWrite = () => resolve(undefined as never);
+                    }),
+            );
+
+        try {
+            const { res, captured } = makeRes();
+            await withActor(owner.actor, () =>
+                callRoute(
+                    'post',
+                    '/rao',
+                    makeReq({ body: { app_uid: app.uid }, actor: owner.actor }),
+                    res,
+                ),
+            );
+
+            // The handler returned while the INSERT is still outstanding.
+            expect(captured.body).toEqual({});
+            expect(writeSpy).toHaveBeenCalled();
+        } finally {
+            releaseWrite();
+            await server.controllers.apps.drainPendingAppOpens();
+            writeSpy.mockRestore();
+        }
+    });
+
+    // A stats failure must never turn into a failed app open — and since the
+    // write is now unawaited, it must not surface as an unhandled rejection.
+    it('swallows a failing stats write without rejecting the request', async () => {
+        const owner = await makeUser();
+        const app = await createApp(owner.actor);
+
+        const writeSpy = vi
+            .spyOn(server.clients.db, 'write')
+            .mockRejectedValue(new Error('primary is down'));
+
+        try {
+            const { res, captured } = makeRes();
+            await withActor(owner.actor, () =>
+                callRoute(
+                    'post',
+                    '/rao',
+                    makeReq({ body: { app_uid: app.uid }, actor: owner.actor }),
+                    res,
+                ),
+            );
+            expect(captured.body).toEqual({});
+            await expect(
+                server.controllers.apps.drainPendingAppOpens(),
+            ).resolves.toBeUndefined();
+        } finally {
+            writeSpy.mockRestore();
+        }
+    });
+
     it('falls back to actor.app.uid when the body omits app_uid', async () => {
         const owner = await makeUser();
         const app = await createApp(owner.actor);
@@ -354,6 +425,8 @@ describe('AppController POST /rao', () => {
         );
         expect(captured.body).toEqual({});
 
+        await server.controllers.apps.drainPendingAppOpens();
+
         const rows = (await server.clients.db.read(
             'SELECT `app_uid` FROM `app_opens` WHERE `app_uid` = ? AND `user_id` = ?',
             [app.uid, owner.userId],
@@ -427,6 +500,73 @@ describe('AppController GET /apps/:name', () => {
         expect((arr[0] as Record<string, unknown>).uid).toBe(app.uid);
         expect(arr[1]).toBeNull();
     });
+
+    // The driver is the authoritative producer of launch metadata: it runs
+    // the hosted-subdomain guard, which this route knows nothing about. The
+    // route's own entitlement re-check must never turn that denial into an
+    // affirmative verdict — the GUI launcher appends `puter.auth.token` to
+    // whatever `index_url` it is handed.
+
+    it('preserves the hosted-backing denial for the app owner', async () => {
+        const owner = await makeUser();
+        const sub = uniqueName('gone');
+        const row = await server.stores.subdomain.create({
+            userId: owner.userId,
+            subdomain: sub,
+        });
+        const app = await createApp(owner.actor, {
+            index_url: `https://${sub}.site.puter.localhost/`,
+        });
+        await server.stores.subdomain.deleteByUuid(
+            String((row as { uuid: string }).uuid),
+            { userId: owner.userId },
+        );
+
+        const { res, captured } = makeRes();
+        await withActor(owner.actor, () =>
+            callRoute(
+                'get',
+                '/apps/:name',
+                makeReq({ params: { name: app.name }, actor: owner.actor }),
+                res,
+            ),
+        );
+        const body = captured.body as Record<string, unknown>;
+        expect(body.privateAccess).toMatchObject({
+            hasAccess: false,
+            reason: 'hosted_backing_unavailable',
+        });
+    });
+
+    it('omits the stale index_url for a non-owner', async () => {
+        const owner = await makeUser();
+        const stranger = await makeUser();
+        const sub = uniqueName('gone');
+        const row = await server.stores.subdomain.create({
+            userId: owner.userId,
+            subdomain: sub,
+        });
+        const app = await createApp(owner.actor, {
+            index_url: `https://${sub}.site.puter.localhost/`,
+        });
+        await server.stores.subdomain.deleteByUuid(
+            String((row as { uuid: string }).uuid),
+            { userId: owner.userId },
+        );
+
+        const { res, captured } = makeRes();
+        await withActor(stranger.actor, () =>
+            callRoute(
+                'get',
+                '/apps/:name',
+                makeReq({ params: { name: app.name }, actor: stranger.actor }),
+                res,
+            ),
+        );
+        const body = captured.body as Record<string, unknown>;
+        expect(body.index_url).toBeUndefined();
+        expect(body.privateAccess).toMatchObject({ hasAccess: false });
+    });
 });
 
 // ── POST /query/app ─────────────────────────────────────────────────
@@ -649,7 +789,9 @@ describe('AppController GET /app-icon/:app_uid', () => {
 
     it('decodes a data URL icon and serves the declared MIME', async () => {
         const owner = await makeUser();
-        const png = Buffer.from('mock-png-bytes');
+        // Real PNG bytes: the write path sniffs the decoded payload and
+        // rejects anything that isn't the image type it claims to be.
+        const png = Buffer.from(MINIMAL_PNG_BASE64, 'base64');
         const dataUrl = `data:image/png;base64,${png.toString('base64')}`;
         const app = await createApp(owner.actor, { icon: dataUrl });
 
@@ -666,6 +808,25 @@ describe('AppController GET /app-icon/:app_uid', () => {
         expect((captured.body as Buffer).equals(png)).toBe(true);
     });
 
+    // Icons are fetched on every app launch, over a connection the launch is
+    // already competing for. The inline path must not be cached more briefly
+    // than the redirect path that serves the same resource.
+    it('caches an inline data-URL icon as long as the redirect path', async () => {
+        const owner = await makeUser();
+        const dataUrl = `data:image/png;base64,${MINIMAL_PNG_BASE64}`;
+        const app = await createApp(owner.actor, { icon: dataUrl });
+
+        const { res, captured } = makeRes();
+        await callRoute(
+            'get',
+            '/app-icon/:app_uid',
+            makeReq({ params: { app_uid: app.uid } }),
+            res,
+        );
+
+        expect(captured.headers['cache-control']).toBe('public, max-age=900');
+    });
+
     it('falls back to the default icon when the data-URL MIME is not allowlisted', async () => {
         const owner = await makeUser();
         // text/html is NOT in the icon allowlist — must NOT be echoed back.
@@ -707,3 +868,153 @@ describe('AppController GET /app-icon/:app_uid', () => {
         expect(captured.statusCode).toBe(200);
     });
 });
+
+// ── /rao actor gating ───────────────────────────────────────────────
+
+describe('AppController POST /rao actor gating', () => {
+    it('refuses to record an open for a scoped access token', async () => {
+        const { actor } = await makeUser();
+        const app = await createApp(actor);
+        // Shared / scoped credentials must not drive analytics counters.
+        const tokenActor = {
+            ...actor,
+            accessToken: { uuid: uuidv4(), permissions: [] },
+        } as unknown as Actor;
+
+        const { res } = makeRes();
+        await expect(
+            withActor(tokenActor, () =>
+                callRoute(
+                    'post',
+                    '/rao',
+                    makeReq({
+                        body: { app_uid: app.uid },
+                        actor: tokenActor,
+                    }),
+                    res,
+                ),
+            ),
+        ).rejects.toMatchObject({ statusCode: 403, legacyCode: 'forbidden' });
+    });
+
+    it("refuses to let an app actor record another app's open", async () => {
+        const { actor } = await makeUser();
+        const own = await createApp(actor);
+        const other = await createApp(actor);
+        const appActor = {
+            ...actor,
+            app: { uid: own.uid as string },
+        } as unknown as Actor;
+
+        const { res } = makeRes();
+        await expect(
+            withActor(appActor, () =>
+                callRoute(
+                    'post',
+                    '/rao',
+                    makeReq({
+                        body: { app_uid: other.uid },
+                        actor: appActor,
+                    }),
+                    res,
+                ),
+            ),
+        ).rejects.toMatchObject({ statusCode: 403, legacyCode: 'forbidden' });
+    });
+});
+
+// ── app-icon redirect + fallback paths ──────────────────────────────
+
+describe('AppController GET /app-icon remote icons', () => {
+    // AppDriver.create validates the `icon` column, so these fixtures write
+    // it straight to the row. AppStore caches by uid — drop that entry or the
+    // handler reads the pre-update app back.
+    const setIcon = async (uid: string, icon: string) => {
+        await server.clients.db.write(
+            'UPDATE `apps` SET `icon` = ? WHERE `uid` = ?',
+            [icon, uid],
+        );
+        await server.stores.app.invalidateByUid(uid);
+    };
+
+    it('redirects to an icon hosted on a trusted host', async () => {
+        const owner = await makeUser();
+        const app = await createApp(owner.actor);
+        const { static_hosting_domain: hostingDomain } = (
+            server.controllers.apps as unknown as {
+                config: { static_hosting_domain: string };
+            }
+        ).config;
+        const trusted = `https://puter-app-icons.${hostingDomain}/${app.uid}-128.png`;
+        await setIcon(String(app.uid), trusted);
+
+        const { res, captured } = makeRes();
+        await callRoute(
+            'get',
+            '/app-icon/:app_uid',
+            makeReq({ params: { app_uid: app.uid } }),
+            res,
+        );
+        expect(captured.redirectStatus).toBe(302);
+        expect(captured.redirectUrl).toBe(trusted);
+        expect(captured.headers['cache-control']).toBe('public, max-age=900');
+    });
+
+    it('never redirects to an icon URL on an untrusted host', async () => {
+        const owner = await makeUser();
+        const app = await createApp(owner.actor);
+        // An open redirect here would let an app row point browsers anywhere.
+        await setIcon(String(app.uid), 'https://evil.example.com/icon.png');
+
+        const { res, captured } = makeRes();
+        await callRoute(
+            'get',
+            '/app-icon/:app_uid',
+            makeReq({ params: { app_uid: app.uid } }),
+            res,
+        );
+        expect(captured.redirectUrl).toBeUndefined();
+        expect(captured.headers['content-type']).toContain('image/svg+xml');
+    });
+
+    it('serves the default icon for a malformed data URL with no comma', async () => {
+        const owner = await makeUser();
+        const app = await createApp(owner.actor);
+        await setIcon(String(app.uid), 'data:image/png;base64');
+
+        const { res, captured } = makeRes();
+        await callRoute(
+            'get',
+            '/app-icon/:app_uid',
+            makeReq({ params: { app_uid: app.uid } }),
+            res,
+        );
+        expect(captured.headers['content-type']).toContain('image/svg+xml');
+    });
+
+    it('serves the default icon for an unknown app uid', async () => {
+        const { res, captured } = makeRes();
+        await callRoute(
+            'get',
+            '/app-icon/:app_uid',
+            makeReq({ params: { app_uid: `app-${uuidv4()}` } }),
+            res,
+        );
+        expect(captured.headers['content-type']).toContain('image/svg+xml');
+    });
+
+    it('serves the default icon for a bare (non-URL, non-data) icon value', async () => {
+        const owner = await makeUser();
+        const app = await createApp(owner.actor);
+        await setIcon(String(app.uid), 'legacy-icon-name.png');
+
+        const { res, captured } = makeRes();
+        await callRoute(
+            'get',
+            '/app-icon/:app_uid/:size',
+            makeReq({ params: { app_uid: app.uid, size: '64' } }),
+            res,
+        );
+        expect(captured.headers['content-type']).toContain('image/svg+xml');
+    });
+});

src/backend/controllers/apps/default-app-icon.js

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.

src/backend/controllers/auth/AuthController.ts

@@ -1,21 +1,20 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
  *
- * Puter is free software: you can redistribute it and/or modify it under the
- * terms of the GNU Affero General Public License as published by the Free
- * Software Foundation, either version 3 of the License, or (at your option) any
- * later version.
+ * Puter is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
  *
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
- * FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
- * details.
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
  *
  * You should have received a copy of the GNU Affero General Public License
- * along with this program. If not, see
- * [https://www.gnu.org/licenses/](https://www.gnu.org/licenses/).
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
 import bcrypt from 'bcrypt';
@@ -133,6 +132,31 @@ export class AuthController extends PuterController {
                 legacyCode: 'bad_request',
             });
         }
+
+        // Browser-only gate. The session id is client-chosen and travels in a
+        // link, so it is not a secret — the `Origin` header is what actually
+        // says who is asking, and only a browser is prevented from lying about
+        // it. A caller with no `Origin` (curl, a server-side fetch) could
+        // otherwise collect a token minted for someone else's app just by
+        // knowing the id.
+        //
+        // `"null"` is rejected too: sandboxed iframes and `file://` documents
+        // serialise their opaque origin that way, and two *unrelated* opaque
+        // origins would compare equal to each other.
+        const reqOrigin = req.headers.origin;
+        if (!reqOrigin || reqOrigin === 'null') {
+            throw new HttpError(403, 'Origin not allowed', {
+                legacyCode: 'forbidden',
+            });
+        }
+
+        // The app identity this caller is allowed to collect a token for,
+        // derived from the browser-attested header rather than anything in
+        // the request body — so no client, honest or not, can influence the
+        // comparison made after the token arrives.
+        const expectedAppUid =
+            await this.services.auth.appUidFromOrigin(reqOrigin);
+
         const { resolve, promise } = Promise.withResolvers<void>();
 
         let token: string | null = null;
@@ -153,12 +177,56 @@ export class AuthController extends PuterController {
             });
         }
 
+        // Audience check. The postMessage hand-off this relay stands in for
+        // is origin-bound for free — it posts with `targetOrigin`, so a page
+        // can only ever receive a token minted for *itself*. Delivering
+        // server-side dropped that binding; this restores it. Without it a
+        // popup talked into minting for app X (see `trustsOpenerOriginParam`
+        // in the GUI) hands X's token to whoever holds the session id.
+        if (!this.#tokenIsForApp(token, expectedAppUid)) {
+            // Deliberately the same 408 the no-token path returns: a caller
+            // learns only that nothing arrived for them, not that a token
+            // for a different app went past.
+            throw new HttpError(408, 'Request timeout.', {
+                legacyCode: 'request_timeout',
+            });
+        }
+
         res.json({
             auth_token: token,
         });
     }
+
+    /**
+     * Whether a relayed token is an app-under-user token minted for
+     * `expectedAppUid`. Verifies the signature — an unverified decode would let
+     * a caller relay a token whose claims it wrote itself.
+     */
+    #tokenIsForApp(token: string, expectedAppUid: string): boolean {
+        try {
+            const payload = this.services.token.verify<{
+                type?: string;
+                app_uid?: string;
+            }>('auth', token);
+            return (
+                payload.type === 'app-under-user' &&
+                !!payload.app_uid &&
+                payload.app_uid === expectedAppUid
+            );
+        } catch {
+            // Malformed, expired, or signed with a key we don't hold.
+            return false;
+        }
+    }
     @Post('/login/set', {
         subdomain: ['api'],
+        // Unauthenticated fan-out to every `/login/wait` listener on the
+        // session id. A legitimate popup posts here exactly once per sign-in,
+        // so a generous per-IP cap costs honest traffic nothing while denying
+        // an attacker unbounded attempts to land a token on a guessed id.
+        rateLimit: [
+            { scope: 'login-set', limit: 60, window: 15 * 60_000, key: 'ip' },
+        ],
     })
     async loginSet(req: Request, res: Response) {
         const { session, auth_token } = req.body;
@@ -182,6 +250,11 @@ export class AuthController extends PuterController {
     // -- Login -------------------------------------------------------
 
     @Post('/login', {
+        // Returns a full session token in the response body. Reflected CORS
+        // would otherwise let any page trade a password for that token and
+        // read it — third-party sign-in goes through `puter.auth.signIn()`,
+        // whose popup runs on this origin and yields an app-scoped token.
+        guiOriginOnly: true,
         captcha: true,
         // Two limits: per-fingerprint keeps users behind a shared IP
         // (offices, campuses) from throttling each other, while the
@@ -298,6 +371,8 @@ export class AuthController extends PuterController {
     // -- Login: OTP verification -------------------------------------
 
     @Post('/login/otp', {
+        // Second leg of `/login` — also completes into `#completeLogin`.
+        guiOriginOnly: true,
         captcha: true,
         rateLimit: [
             { scope: 'login-otp', limit: 15, window: 30 * 60_000 },
@@ -362,6 +437,8 @@ export class AuthController extends PuterController {
     // -- Login: recovery code ----------------------------------------
 
     @Post('/login/recovery-code', {
+        // Second leg of `/login` — also completes into `#completeLogin`.
+        guiOriginOnly: true,
         captcha: true,
         rateLimit: [
             { scope: 'login-recovery', limit: 10, window: 60 * 60_000 },
@@ -439,6 +516,9 @@ export class AuthController extends PuterController {
     // -- Signup ------------------------------------------------------
 
     @Post('/signup', {
+        // Completes into `#completeLogin`, so it hands back a session token
+        // exactly like `/login`. Same reasoning.
+        guiOriginOnly: true,
         captcha: true,
         rateLimit: [
             { scope: 'signup', limit: 10, window: 15 * 60_000 },
@@ -962,10 +1042,10 @@ export class AuthController extends PuterController {
         antiCsrf: true,
     })
     async handleLogout(req: Request, res: Response): Promise<void> {
-        // Clear the session cookie + the v2 migrate-token companion
-        // cookie (set after `/auth/migrate-token` for app-under-user
-        // iframes). authProbe reads `puter_token_v2` as a fallback, so
-        // a stale value would re-authenticate the next request.
+        // Clear the session cookie + `puter_token_v2`. Nothing issues the
+        // latter any more (it came from the retired token migration), but
+        // authProbe still reads it as a fallback, so a value left in a
+        // browser would re-authenticate the next request.
         res.clearCookie(this.config.cookie_name ?? 'puter_token');
         res.clearCookie('puter_token_v2');
         // Drop any step-up elevation too, so it can't reactivate on a shared
@@ -2258,15 +2338,18 @@ export class AuthController extends PuterController {
         }
         await this.#validateEmail(new_email);
 
-        // Block if any confirmed account (password or OIDC) already
+        // Block if any OTHER confirmed account (password or OIDC) already
         // owns that email. Match raw + canonical to collapse gmail
-        // aliases.
+        // aliases — which is also why the caller has to be excluded: an
+        // alias of your own current address resolves back to you, and
+        // "already in use" about yourself is nonsense.
         const canonical = cleanEmail(new_email);
         const existing =
             (await this.stores.user.getByEmail(new_email)) ??
             (await this.stores.user.getByCleanEmail(canonical));
         if (
             existing &&
+            existing.id !== req.actor!.user.id &&
             (existing.email_confirmed || existing.password !== null)
         ) {
             throw new HttpError(400, 'This email is already in use.', {
@@ -2672,12 +2755,95 @@ export class AuthController extends PuterController {
         res.json({});
     }
 
+    /**
+     * Shared input validation for the user-app grant/revoke handlers, which
+     * accept a caller-supplied `origin` as an alternative to `app_uid`. All
+     * parameters are optional-but-typed: presence is enforced by the handlers'
+     * own `app_uid`/`permission` checks after origin resolution.
+     *
+     * These are bounded only against absurd input. The width of the column a
+     * permission lands in is enforced by the permission service instead, on the
+     * _rewritten_ string: `fs:/path:mode` is rewritten to `fs:<uuid>:mode`
+     * before it is stored, so a deep path is a ~45-character row and must not
+     * be rejected for the length of the path the caller typed.
+     */
+    #validateAppPermissionParams(params: {
+        app_uid?: unknown;
+        origin?: unknown;
+        permission?: unknown;
+        extra?: unknown;
+        meta?: unknown;
+    }): void {
+        const MAX_LEN = 4096;
+        for (const key of ['app_uid', 'origin', 'permission'] as const) {
+            const value = params[key];
+            if (value === undefined || value === null) continue;
+            if (typeof value !== 'string' || value.length > MAX_LEN) {
+                throw new HttpError(400, `Invalid \`${key}\``, {
+                    legacyCode: 'bad_request',
+                });
+            }
+        }
+        // `extra` and `meta` are forwarded into the audit row and read as
+        // objects downstream. A non-object would fault *after* the grant is
+        // committed, so reject it up front. `null` is treated as absent, the
+        // same as the string parameters above.
+        for (const key of ['extra', 'meta'] as const) {
+            const value = params[key];
+            if (value === undefined || value === null) continue;
+            if (typeof value !== 'object' || Array.isArray(value)) {
+                throw new HttpError(400, `Invalid \`${key}\``, {
+                    legacyCode: 'bad_request',
+                });
+            }
+        }
+    }
+
+    /**
+     * Resolves a caller-supplied `origin` to the uid of a _registered_ app.
+     *
+     * `appUidFromOrigin` synthesises a deterministic `app-<uuidv5>` uid for an
+     * origin that has no app row yet, and the permission services resolve their
+     * identifier as uid-_or-name_. Passing a synthetic uid straight through
+     * would therefore let whoever registered an app under that literal name
+     * collect a grant the user made to the origin — the uid is derived from a
+     * published namespace constant, so it can be computed and squatted offline.
+     * Only a uid that names an existing app row is accepted.
+     *
+     * An `origin` supplied alongside an `app_uid` takes precedence over it (see
+     * the grant/revoke handlers). The origin is what a consent prompt shows the
+     * user, so it — not a uid travelling beside it — has to decide who receives
+     * the grant; otherwise a caller could name one app on screen and grant to
+     * another. No caller sends both with different intent.
+     */
+    async #registeredAppUidFromOrigin(origin: string): Promise<string> {
+        const uid = await this.services.auth.appUidFromOrigin(origin);
+        const app = await this.stores.app.getByUid(uid);
+        if (!app) {
+            throw new HttpError(404, `entity_not_found: app:${uid}`, {
+                legacyCode: 'subject_does_not_exist',
+            });
+        }
+        return app.uid;
+    }
+
     @Post('/auth/grant-user-app', {
         subdomain: 'api',
         requireUserActor: true,
     })
     async handleGrantUserApp(req: Request, res: Response): Promise<void> {
-        const { app_uid, permission, extra, meta } = req.body;
+        let { app_uid } = req.body;
+        const { origin, permission, extra, meta } = req.body;
+        this.#validateAppPermissionParams({
+            app_uid,
+            origin,
+            permission,
+            extra,
+            meta,
+        });
+        if (origin) {
+            app_uid = await this.#registeredAppUidFromOrigin(origin);
+        }
         if (!app_uid || !permission) {
             throw new HttpError(400, 'Missing `app_uid` or `permission`', {
                 legacyCode: 'bad_request',
@@ -2687,8 +2853,8 @@ export class AuthController extends PuterController {
             req.actor!,
             app_uid,
             permission,
-            extra,
-            meta,
+            extra ?? undefined,
+            meta ?? undefined,
         );
         res.json({});
     }
@@ -2748,7 +2914,17 @@ export class AuthController extends PuterController {
         requireUserActor: true,
     })
     async handleRevokeUserApp(req: Request, res: Response): Promise<void> {
-        const { app_uid, permission, meta } = req.body;
+        let { app_uid } = req.body;
+        const { origin, permission, meta } = req.body;
+        this.#validateAppPermissionParams({
+            app_uid,
+            origin,
+            permission,
+            meta,
+        });
+        if (origin) {
+            app_uid = await this.#registeredAppUidFromOrigin(origin);
+        }
         if (!app_uid || !permission) {
             throw new HttpError(400, 'Missing `app_uid` or `permission`', {
                 legacyCode: 'bad_request',
@@ -2758,14 +2934,14 @@ export class AuthController extends PuterController {
             await this.services.permission.revokeUserAppAll(
                 req.actor!,
                 app_uid,
-                meta,
+                meta ?? undefined,
             );
         } else {
             await this.services.permission.revokeUserAppPermission(
                 req.actor!,
                 app_uid,
                 permission,
-                meta,
+                meta ?? undefined,
             );
         }
         res.json({});
@@ -2908,7 +3084,15 @@ export class AuthController extends PuterController {
         let { app_uid } = req.body;
         const { origin, permission, extra, meta } = req.body;
         if (origin && !app_uid) {
-            app_uid = await this.services.auth.appUidFromOrigin(origin);
+            // Registered apps only, for the same reason the user-app handlers
+            // insist on it: a synthesised `app-<uuidv5(origin)>` is resolved
+            // downstream as uid-*or-name*, so it would land on whoever
+            // registered an app under that literal name. A dev-app grant is
+            // scanned with the issuer's authority for anyone running as that
+            // app, so that hands this user's permission to the squatter.
+            // Without a squatter the synthetic uid resolves to nothing and
+            // this 404s regardless, so nothing legitimate changes.
+            app_uid = await this.#registeredAppUidFromOrigin(origin);
         }
         if (!app_uid || !permission) {
             throw new HttpError(400, 'Missing `app_uid` or `permission`', {
@@ -2933,7 +3117,8 @@ export class AuthController extends PuterController {
         let { app_uid } = req.body;
         const { origin, permission, meta } = req.body;
         if (origin && !app_uid) {
-            app_uid = await this.services.auth.appUidFromOrigin(origin);
+            // Registered apps only — see handleGrantDevApp.
+            app_uid = await this.#registeredAppUidFromOrigin(origin);
         }
         if (!app_uid || !permission) {
             throw new HttpError(400, 'Missing `app_uid` or `permission`', {
@@ -2946,13 +3131,14 @@ export class AuthController extends PuterController {
                 app_uid,
                 meta,
             );
+        } else {
+            await this.services.permission.revokeDevAppPermission(
+                req.actor!,
+                app_uid,
+                permission,
+                meta,
+            );
         }
-        await this.services.permission.revokeDevAppPermission(
-            req.actor!,
-            app_uid,
-            permission,
-            meta,
-        );
         res.json({});
     }
 
@@ -2968,17 +3154,22 @@ export class AuthController extends PuterController {
 
         const [appPerms, userPermsOut, userPermsIn] = await Promise.all([
             db.read(
-                'SELECT `app_uid`, `permission`, `extra` FROM `user_to_app_permissions` WHERE `user_id` = ?',
+                // The permissions table stores the numeric `app_id` FK; the
+                // public shape exposes the app's `uid`.
+                'SELECT a.`uid` AS app_uid, p.`permission`, p.`extra` ' +
+                    'FROM `user_to_app_permissions` p ' +
+                    'JOIN `apps` a ON a.`id` = p.`app_id` ' +
+                    'WHERE p.`user_id` = ?',
                 [userId],
             ),
             db.read(
                 'SELECT u.`username`, p.`permission`, p.`extra` FROM `user_to_user_permissions` p ' +
-                    'JOIN `user` u ON u.`id` = p.`target_user_id` WHERE p.`issuer_user_id` = ?',
+                    'JOIN `user` u ON u.`id` = p.`holder_user_id` WHERE p.`issuer_user_id` = ?',
                 [userId],
             ),
             db.read(
                 'SELECT u.`username`, p.`permission`, p.`extra` FROM `user_to_user_permissions` p ' +
-                    'JOIN `user` u ON u.`id` = p.`issuer_user_id` WHERE p.`target_user_id` = ?',
+                    'JOIN `user` u ON u.`id` = p.`issuer_user_id` WHERE p.`holder_user_id` = ?',
                 [userId],
             ),
         ]);
@@ -3065,9 +3256,9 @@ export class AuthController extends PuterController {
                 legacyCode: 'not_found',
             });
         }
-        // Grant the app-is-authenticated flag
+
         const userPermGrantPromise =
-            await this.services.permission.grantUserAppPermission(
+            this.services.permission.grantUserAppPermission(
                 req.actor!,
                 app_uid,
                 'flag:app-is-authenticated',
@@ -3075,7 +3266,7 @@ export class AuthController extends PuterController {
                 {},
             );
 
-        const token = await this.services.auth.getUserAppToken(
+        const tokenPromise = this.services.auth.getUserAppToken(
             req.actor!,
             app_uid,
         );
@@ -3102,7 +3293,11 @@ export class AuthController extends PuterController {
             }
         })();
 
-        await Promise.all([userPermGrantPromise, missingFSPathPromise]);
+        const [, token] = await Promise.all([
+            userPermGrantPromise,
+            tokenPromise,
+            missingFSPathPromise,
+        ]);
 
         try {
             const a = app as {
@@ -3170,84 +3365,6 @@ export class AuthController extends PuterController {
 
     // -- Access tokens -----------------------------------------------
 
-    async handleMigrateToken(req: Request, res: Response): Promise<void> {
-        // 1. Browser-only gate. No Origin header → reject (server-side
-        // callers should re-auth properly). The exchange itself is open
-        // to any browser origin: puter.js apps live on arbitrary
-        // third-party domains, the v1 bearer token is the credential,
-        // and cookies are never read here — so a hostile page learns
-        // nothing it doesn't already hold. Origin *trust* only decides
-        // whether the `puter_token_v2` companion cookie is set below.
-        const reqOrigin = req.headers.origin;
-        if (!reqOrigin) {
-            throw new HttpError(403, 'Origin not allowed', {
-                legacyCode: 'forbidden',
-            });
-        }
-
-        // 2. Extract token. Header takes precedence so body-capture logs
-        // (if any) never see the credential.
-        const authHeader = req.headers.authorization;
-        const headerToken =
-            typeof authHeader === 'string' && authHeader.startsWith('Bearer ')
-                ? authHeader.slice('Bearer '.length).trim()
-                : null;
-        const bodyToken =
-            typeof req.body?.token === 'string' ? req.body.token.trim() : null;
-        const v1Token = headerToken || bodyToken;
-        if (!v1Token) {
-            throw new HttpError(400, 'Missing token', {
-                legacyCode: 'bad_request',
-            });
-        }
-
-        const result = await this.services.auth.migrateLegacyToken(v1Token, {
-            ip: req.ip,
-            userAgent:
-                typeof req.headers['user-agent'] === 'string'
-                    ? req.headers['user-agent']
-                    : undefined,
-        });
-        // `puter_token_v2` is the cookie companion to v2 app tokens —
-        // it lets the GUI's cookie-only middleware authenticate
-        // subsequent same-origin calls without the client forwarding
-        // Authorization headers. Issuing it is gated on the trusted
-        // origin allowlist: an arbitrary attacker page must not be able
-        // to plant a session cookie on the GUI origin (login CSRF).
-        // Untrusted origins still get the token in the JSON body — the
-        // cookie is only consumed same-origin (see authProbe) so they
-        // lose nothing. Access tokens are programmatic (no browser
-        // cookie surface) so we deliberately skip them here.
-        if (
-            result.kind === 'app' &&
-            this.#isMigrateTokenOriginAllowed(reqOrigin)
-        ) {
-            res.cookie('puter_token_v2', result.token, {
-                ...sessionCookieFlags(this.config),
-                httpOnly: true,
-            });
-        }
-        res.json(result);
-    }
-
-    #isMigrateTokenOriginAllowed(origin: string): boolean {
-        // Origin headers and config values both reach us in inconsistent
-        // shapes (trailing slash, mixed case from misconfigured deploys,
-        // stray whitespace from JSON config edits). Normalize both sides
-        // before equality so a `config.origin` with a trailing slash
-        // doesn't reject every same-origin browser call.
-        const normalize = (raw: string | undefined): string =>
-            (raw ?? '').trim().replace(/\/+$/, '').toLowerCase();
-        const incoming = normalize(origin);
-        if (!incoming) return false;
-        if (incoming === normalize(this.config.origin)) return true;
-        const allowlist = (
-            this.config as { allow_migrate_token_origins?: string[] }
-        ).allow_migrate_token_origins;
-        if (!Array.isArray(allowlist)) return false;
-        return allowlist.some((entry) => normalize(entry) === incoming);
-    }
-
     @Post('/auth/create-access-token', {
         subdomain: 'api',
         requireAuth: true,
@@ -3609,10 +3726,24 @@ export class AuthController extends PuterController {
     }
 
     @Get('/session/sync-cookie', {
+        // Installs the session cookie. Only page script on our own origin
+        // should be able to ask for that (the `tokenSource` check below is the
+        // companion rule: the token has to come from an Authorization header,
+        // not a URL).
+        guiOriginOnly: true,
         requireUserActor: true,
         allowUnconfirmed: true,
     })
     async handleSessionSyncCookie(req: Request, res: Response): Promise<void> {
+        // This route installs a session cookie, so the token has to come from
+        // page script on our own origin rather than from the URL.
+        if (req.tokenSource !== 'header') {
+            throw new HttpError(
+                401,
+                'This endpoint requires an Authorization header.',
+                { legacyCode: 'token_auth_failed' },
+            );
+        }
         if (!req.actor?.session?.uid) {
             res.status(400).end();
             return;
@@ -3964,19 +4095,6 @@ export class AuthController extends PuterController {
             },
             (req, res) => this.handleRenameSession(req, res),
         );
-
-        router.post(
-            '/auth/migrate-token',
-            {
-                rateLimit: {
-                    scope: 'migrate-token',
-                    limit: 20,
-                    window: 15 * 60_000,
-                    key: 'ip',
-                },
-            },
-            (req, res) => this.handleMigrateToken(req, res),
-        );
     }
 
     // -- Private helpers ----------------------------------------------

src/backend/controllers/auth/authOriginGating.test.ts

@@ -0,0 +1,103 @@
+/*
+ * Copyright (C) 2024-present Puter Technologies Inc.
+ *
+ * This file is part of Puter.
+ *
+ * Puter is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+/**
+ * Wiring test for `guiOriginOnly`.
+ *
+ * `originGate.test.ts` covers what the gate decides. This covers that the
+ * routes which hand a session credential back to the caller actually opt into
+ * it — a correct gate wired to nothing protects nothing, and the failure is
+ * invisible (the route keeps working, just for everybody).
+ */
+
+import { describe, expect, it } from 'vitest';
+import { AuthController } from './AuthController.js';
+import {
+    ROUTES_METADATA_KEY,
+    type CollectedRoute,
+} from '../../core/http/types.js';
+
+// The decorators register on the prototype via `addInitializer`, which only
+// runs once an instance exists. We never start this one — constructing it is
+// enough to populate the route metadata.
+const collectRoutes = (): CollectedRoute[] => {
+    const proto = AuthController.prototype as unknown as Record<
+        string,
+        CollectedRoute[] | undefined
+    >;
+    if (!proto[ROUTES_METADATA_KEY]) {
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        new (AuthController as any)({}, {}, {}, {}, {});
+    }
+    return proto[ROUTES_METADATA_KEY] ?? [];
+};
+
+/**
+ * Every route that answers with a usable session credential. Adding one here
+ * without `guiOriginOnly` is the mistake this test exists to catch: reflected
+ * CORS would let any page read the credential out of the response.
+ */
+const CREDENTIAL_ROUTES: Array<[method: string, path: string]> = [
+    ['post', '/login'],
+    ['post', '/login/otp'],
+    ['post', '/login/recovery-code'],
+    ['post', '/signup'],
+    ['get', '/session/sync-cookie'],
+];
+
+describe('guiOriginOnly wiring on AuthController', () => {
+    const routes = collectRoutes();
+
+    it('registers the routes under test at all (guards against a rename)', () => {
+        for (const [method, path] of CREDENTIAL_ROUTES) {
+            const found = routes.find(
+                (r) => r.method === method && r.path === path,
+            );
+            expect(found, `${method.toUpperCase()} ${path} not registered`)
+                .toBeDefined();
+        }
+    });
+
+    it.each(CREDENTIAL_ROUTES)(
+        'gates %s %s to the GUI origin',
+        (method, path) => {
+            const route = routes.find(
+                (r) => r.method === method && r.path === path,
+            );
+            expect(route?.options.guiOriginOnly).toBe(true);
+        },
+    );
+
+    // The popup relay is the third-party sign-in path: `puter.auth.signIn()`
+    // polls `/login/wait` from whatever origin the app is served from, and
+    // `/login/set` is posted by the popup. Gating either to our own origin
+    // would break every third-party app, and neither needs it — the token
+    // they move is app-scoped, not a session.
+    it.each([
+        ['post', '/login/wait'],
+        ['post', '/login/set'],
+    ])('leaves %s %s open cross-origin', (method, path) => {
+        const route = routes.find(
+            (r) => r.method === method && r.path === path,
+        );
+        expect(route, `${method.toUpperCase()} ${path} not registered`)
+            .toBeDefined();
+        expect(route?.options.guiOriginOnly).toBeUndefined();
+    });
+});

src/backend/controllers/broadcast/BroadcastController.test.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.

src/backend/controllers/broadcast/BroadcastController.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -27,20 +27,19 @@ import { PuterController } from '../types.js';
  *
  * The route is intentionally a thin shell: parse the four custom
  * `X-Broadcast-*` headers, hand the raw body + parsed body off to
- * `BroadcastService.verifyAndEmit()`, and translate its structured
- * result into HTTP. All the cryptography, replay protection, and
- * event-bus dispatch live in the service so they're reusable from
- * tests / direct callers.
+ * `BroadcastService.verifyAndEmit()`, and translate its structured result into
+ * HTTP. All the cryptography, replay protection, and event-bus dispatch live in
+ * the service so they're reusable from tests / direct callers.
  *
- * Mounted with `subdomain: '*'` (any host) because peers reach the
- * webhook through the ALB DNS, not the public `api.<domain>` subdomain,
- * so the host header can be an internal ALB hostname rather than
- * `api.<domain>` or `<domain>`. Authentication is via the HMAC +
- * peer-id + nonce triple, not the host.
+ * Mounted with `subdomain: '*'` (any host) because peers reach the webhook
+ * through the ALB DNS, not the public `api.<domain>` subdomain, so the host
+ * header can be an internal ALB hostname rather than `api.<domain>` or
+ * `<domain>`. Authentication is via the HMAC + peer-id + nonce triple, not the
+ * host.
  *
- * `req.rawBody` is captured by the global JSON parser and is what the
- * HMAC verifies against — do NOT switch this route to a custom body
- * parser without preserving the raw bytes.
+ * `req.rawBody` is captured by the global JSON parser and is what the HMAC
+ * verifies against — do NOT switch this route to a custom body parser without
+ * preserving the raw bytes.
  */
 @Controller('/broadcast')
 export class BroadcastController extends PuterController {

src/backend/controllers/desktop/DesktopController.js

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -28,8 +28,9 @@ const ALLOWED_SORT_ORDER = ['asc', 'desc'];
  * Desktop/UI preference routes.
  *
  * Two categories:
- *   - User-level: desktop background, taskbar items (UserStore)
- *   - Folder-level: layout, sort_by/sort_order (fsentries table)
+ *
+ * - User-level: desktop background, taskbar items (UserStore)
+ * - Folder-level: layout, sort_by/sort_order (fsentries table)
  */
 export class DesktopController extends PuterController {
     constructor(config, clients, stores, services) {
@@ -195,16 +196,15 @@ export class DesktopController extends PuterController {
     // -- Helpers ------------------------------------------------------
 
     /**
-     * Update columns on an actor-owned fsentry. Accepts either `item_uid`
-     * (fast path) or `item_path` (path lookups in FSEntryStore now have
-     * a recursive-CTE fallback for legacy rows with a NULL `path` column,
-     * so this works for old accounts too).
+     * Update columns on an actor-owned fsentry. Accepts either `item_uid` (fast
+     * path) or `item_path` (path lookups in FSEntryStore now have a
+     * recursive-CTE fallback for legacy rows with a NULL `path` column, so this
+     * works for old accounts too).
      *
-     * Ownership: `entry.user_id === actor.user.id`. Kept as added
-     * validation against bad paths — the previous "drop user_id entirely"
-     * theory turned out to be wrong (the actual legacy issue was NULL
-     * paths, not user_id drift), so this filter doesn't lock out old
-     * accounts in practice.
+     * Ownership: `entry.user_id === actor.user.id`. Kept as added validation
+     * against bad paths — the previous "drop user_id entirely" theory turned
+     * out to be wrong (the actual legacy issue was NULL paths, not user_id
+     * drift), so this filter doesn't lock out old accounts in practice.
      */
     async #updateFSEntry(actor, { item_uid, item_path }, patch) {
         if (!item_uid && !item_path) {

src/backend/controllers/desktop/DesktopController.test.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.

src/backend/controllers/drivers/DriverController.concurrent.test.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.

src/backend/controllers/drivers/DriverController.errors.test.ts

@@ -0,0 +1,438 @@
+/**
+ * Copyright (C) 2024-present Puter Technologies Inc.
+ *
+ * This file is part of Puter.
+ *
+ * Puter is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+/**
+ * Upstream-error translation and rate-limit rejection in `/drivers/call`.
+ *
+ * When a driver's upstream provider fails, the caller must see a stable Puter
+ * error code rather than a raw vendor payload. Each SDK reports its status
+ * differently (`status`, `response.status`, an AWS `$metadata` block, or only a
+ * message), so the controller sniffs all four — this suite pins the mapping for
+ * every shape and asserts the resulting `legacyCode` / `statusCode`, plus the
+ * `upstreamStatus` / `upstreamCode` diagnostic fields.
+ *
+ * The synthetic driver stands in for a provider-backed one: it is the input to
+ * the translation under test, and it lets a single controller instance cover
+ * every failure shape without real provider credentials.
+ */
+
+/* eslint-disable @typescript-eslint/no-explicit-any */
+import { Readable, Writable } from 'node:stream';
+import type { Request, RequestHandler, Response } from 'express';
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import type { DriverMethodLifecycleEvent } from '../../clients/event/types.js';
+import { runWithContext } from '../../core/context.js';
+import { configureRateLimit } from '../../core/http/middleware/rateLimit.js';
+import { DriverController } from './DriverController.js';
+
+// -- Harness ---------------------------------------------------------
+
+const captureCallHandler = (controller: DriverController): RequestHandler => {
+    let handler: RequestHandler | undefined;
+    const fakeRouter = {
+        post: (path: string, _opts: unknown, h: RequestHandler) => {
+            if (path === '/call') handler = h;
+            return fakeRouter;
+        },
+        get: () => fakeRouter,
+        use: () => fakeRouter,
+    };
+    controller.registerRoutes(fakeRouter as any);
+    if (!handler) throw new Error('failed to capture POST /call handler');
+    return handler;
+};
+
+// A real Writable so `result.stream.pipe(res)` behaves like the express
+// response it stands in for.
+class MockRes extends Writable {
+    statusCode = 200;
+    body: unknown;
+    headers: Record<string, string> = {};
+    chunks: Buffer[] = [];
+    override _write(
+        chunk: Buffer,
+        _enc: BufferEncoding,
+        cb: (e?: Error) => void,
+    ) {
+        this.chunks.push(Buffer.from(chunk));
+        cb();
+    }
+    status(code: number) {
+        this.statusCode = code;
+        return this;
+    }
+    json(body: unknown) {
+        this.body = body;
+        return this;
+    }
+    setHeader(k: string, v: string) {
+        this.headers[k.toLowerCase()] = v;
+        return this;
+    }
+}
+
+const makeReq = (body: Record<string, unknown>): Request =>
+    ({
+        body,
+        headers: {},
+        query: {},
+        ip: '127.0.0.1',
+        socket: { remoteAddress: '127.0.0.1' },
+    }) as unknown as Request;
+
+interface BuildOptions {
+    run?: () => unknown;
+    rateLimit?: unknown;
+    /**
+     * Rate-limit buckets are keyed by iface+method, so give tests that exercise
+     * limits their own namespace.
+     */
+    iface?: string;
+}
+
+/**
+ * Build a controller around one synthetic driver. No actor is attached, so the
+ * permission scan is skipped and the call reaches the driver method.
+ */
+const build = (opts: BuildOptions = {}) => {
+    const events: DriverMethodLifecycleEvent[] = [];
+    const eventClient = {
+        emitAndWait: vi.fn(async () => {}),
+        emit: vi.fn((_key: string, payload: unknown) => {
+            events.push(payload as DriverMethodLifecycleEvent);
+        }),
+        on: vi.fn(),
+    };
+    const alarms: Array<{ id: string; severity: string }> = [];
+    const iface = opts.iface ?? 'test-iface';
+    const driver = {
+        driverInterface: iface,
+        driverName: 'test-driver',
+        isDefault: true,
+        ...(opts.rateLimit ? { rateLimit: opts.rateLimit } : {}),
+        run:
+            opts.run ??
+            (() => {
+                throw new Error('no run configured');
+            }),
+    };
+    const controller = new DriverController(
+        {} as any,
+        {
+            event: eventClient,
+            alarm: {
+                create: (id: string, _t: string, _f: unknown, sev: string) => {
+                    alarms.push({ id, severity: sev });
+                },
+            },
+        } as any,
+        {} as any,
+        {} as any,
+        { testDriver: driver } as any,
+    );
+    return {
+        handler: captureCallHandler(controller),
+        events,
+        alarms,
+        driver,
+        iface,
+    };
+};
+
+const callWith = async (run: () => unknown) => {
+    const { handler, events } = build({ run });
+    const res = new MockRes();
+    const err = await runWithContext({}, () =>
+        handler(
+            makeReq({ interface: 'test-iface', method: 'run' }),
+            res as unknown as Response,
+            () => {},
+        ),
+    ).then(
+        () => null,
+        (e: unknown) => e,
+    );
+    return { err, res, events };
+};
+
+const throwing = (payload: unknown) => () => {
+    throw payload;
+};
+
+// -- Upstream status extraction --------------------------------------
+
+describe('DriverController upstream error translation', () => {
+    it('maps an upstream 429 to a Puter 429 with upstream_rate_limited', async () => {
+        const { err } = await callWith(
+            throwing(
+                Object.assign(new Error('slow down'), {
+                    status: 429,
+                    code: 'rate_limit_exceeded',
+                }),
+            ),
+        );
+        expect(err).toMatchObject({
+            statusCode: 429,
+            legacyCode: 'upstream_rate_limited',
+            message: 'slow down',
+            fields: {
+                upstreamStatus: 429,
+                upstreamCode: 'rate_limit_exceeded',
+            },
+        });
+    });
+
+    it('maps upstream 401 and 403 to a 500 upstream_auth_failed — never leaking auth state to the caller', async () => {
+        for (const status of [401, 403]) {
+            const { err } = await callWith(
+                throwing(Object.assign(new Error('bad key'), { status })),
+            );
+            expect(err).toMatchObject({
+                statusCode: 500,
+                legacyCode: 'upstream_auth_failed',
+                fields: { upstreamStatus: status },
+            });
+        }
+    });
+
+    it('maps any upstream 5xx to a 400 upstream_provider_unavailable with a generic message', async () => {
+        const { err } = await callWith(
+            throwing(
+                Object.assign(new Error('internal provider stack trace'), {
+                    status: 503,
+                }),
+            ),
+        );
+        expect(err).toMatchObject({
+            statusCode: 400,
+            legacyCode: 'upstream_provider_unavailable',
+            message: 'AI provider unavailable',
+            fields: { upstreamStatus: 503 },
+        });
+    });
+
+    it('maps a generic upstream 4xx to a 400 upstream_bad_request', async () => {
+        const { err } = await callWith(
+            throwing(
+                Object.assign(new Error('unsupported parameter'), {
+                    status: 422,
+                }),
+            ),
+        );
+        expect(err).toMatchObject({
+            statusCode: 400,
+            legacyCode: 'upstream_bad_request',
+            message: 'unsupported parameter',
+            fields: { upstreamStatus: 422 },
+        });
+    });
+
+    it('prefers the nested error.message and error.code over the top-level ones', async () => {
+        const { err } = await callWith(
+            throwing({
+                status: 400,
+                message: 'outer',
+                code: 'outer_code',
+                error: { message: 'inner detail', code: 'inner_code' },
+            }),
+        );
+        expect(err).toMatchObject({
+            legacyCode: 'upstream_bad_request',
+            message: 'inner detail',
+            fields: { upstreamStatus: 400, upstreamCode: 'inner_code' },
+        });
+    });
+
+    it('reads the status from statusCode when `status` is absent', async () => {
+        const { err } = await callWith(throwing({ statusCode: 429 }));
+        expect(err).toMatchObject({
+            statusCode: 429,
+            legacyCode: 'upstream_rate_limited',
+        });
+    });
+
+    it('reads the status from a nested response object (axios-style)', async () => {
+        const { err } = await callWith(
+            throwing({ response: { status: 429 }, message: 'axios rejected' }),
+        );
+        expect(err).toMatchObject({
+            statusCode: 429,
+            legacyCode: 'upstream_rate_limited',
+            fields: { upstreamStatus: 429 },
+        });
+    });
+
+    it('reads the status from an AWS $metadata block', async () => {
+        const { err } = await callWith(
+            throwing({
+                $metadata: { httpStatusCode: 400 },
+                message: 'ValidationException',
+            }),
+        );
+        expect(err).toMatchObject({
+            statusCode: 400,
+            legacyCode: 'upstream_bad_request',
+            fields: { upstreamStatus: 400 },
+        });
+    });
+
+    it('sniffs a status out of the message when nothing else carries one', async () => {
+        const { err } = await callWith(
+            throwing(new Error('Request failed with status code 422')),
+        );
+        expect(err).toMatchObject({
+            statusCode: 400,
+            legacyCode: 'upstream_bad_request',
+            fields: { upstreamStatus: 422 },
+        });
+    });
+
+    it('does not treat a bare 4xx-looking number in the message as a status', async () => {
+        const raw = new Error('the answer contained 404 rows');
+        const { err } = await callWith(throwing(raw));
+        // No status could be derived, so the original error passes through
+        // untranslated rather than being mislabelled.
+        expect(err).toBe(raw);
+    });
+
+    it('passes an HttpError from the driver straight through', async () => {
+        const { HttpError } = await import('../../core/http/HttpError.js');
+        const raw = new HttpError(404, 'no such key', {
+            legacyCode: 'not_found',
+        });
+        const { err } = await callWith(throwing(raw));
+        expect(err).toBe(raw);
+    });
+
+    it('passes non-object throwables through untouched', async () => {
+        const { err } = await callWith(throwing('a bare string'));
+        expect(err).toBe('a bare string');
+    });
+
+    it('passes an error with a sub-400 status through untranslated', async () => {
+        const raw = { status: 302, message: 'redirected' };
+        const { err } = await callWith(throwing(raw));
+        expect(err).toBe(raw);
+    });
+
+    it('emits the error lifecycle event with the original (untranslated) error', async () => {
+        const raw = Object.assign(new Error('provider down'), { status: 500 });
+        const { events, err } = await callWith(throwing(raw));
+
+        const errorEvent = events.find(
+            (e) => (e as { phase?: string }).phase === 'error',
+        ) as unknown as Record<string, unknown>;
+        expect(errorEvent).toBeDefined();
+        expect(errorEvent.iface).toBe('test-iface');
+        expect(errorEvent.method).toBe('run');
+        expect(errorEvent.driver).toBe('test-driver');
+        expect(errorEvent.error).toBe(raw);
+        expect(typeof errorEvent.durationMs).toBe('number');
+        // The caller still sees the translated error.
+        expect(err).toMatchObject({
+            legacyCode: 'upstream_provider_unavailable',
+        });
+    });
+});
+
+// -- Stream results --------------------------------------------------
+
+describe('DriverController stream responses', () => {
+    it('sets Transfer-Encoding: chunked for a chunked stream result', async () => {
+        const { handler } = build({
+            run: () => ({
+                dataType: 'stream',
+                content_type: 'audio/mpeg',
+                chunked: true,
+                stream: Readable.from(['a', 'b']),
+            }),
+        });
+        const res = new MockRes();
+
+        await runWithContext({}, () =>
+            handler(
+                makeReq({ interface: 'test-iface', method: 'run' }),
+                res as unknown as Response,
+                () => {},
+            ),
+        );
+
+        expect(res.headers['content-type']).toBe('audio/mpeg');
+        expect(res.headers['transfer-encoding']).toBe('chunked');
+        // A piped stream never produces a JSON body.
+        expect(res.body).toBeUndefined();
+    });
+
+    it('omits Transfer-Encoding for a non-chunked stream result', async () => {
+        const { handler } = build({
+            run: () => ({
+                dataType: 'stream',
+                content_type: 'audio/mpeg',
+                stream: Readable.from(['a']),
+            }),
+        });
+        const res = new MockRes();
+
+        await runWithContext({}, () =>
+            handler(
+                makeReq({ interface: 'test-iface', method: 'run' }),
+                res as unknown as Response,
+                () => {},
+            ),
+        );
+
+        expect(res.headers['content-type']).toBe('audio/mpeg');
+        expect('transfer-encoding' in res.headers).toBe(false);
+    });
+});
+
+// -- Rate limiting ---------------------------------------------------
+
+describe('DriverController per-method rate limiting', () => {
+    beforeEach(() => {
+        configureRateLimit({ disabled: false } as never);
+    });
+
+    it('answers 429 and raises a de-duped info alarm once the per-method budget is spent', async () => {
+        const { handler, alarms, iface } = build({
+            run: () => ({ ok: true }),
+            rateLimit: { default: { limit: 1, window: 60_000 } },
+            iface: 'rate-limited-iface',
+        });
+        const call = () =>
+            runWithContext({}, () =>
+                handler(
+                    makeReq({ interface: iface, method: 'run' }),
+                    new MockRes() as unknown as Response,
+                    () => {},
+                ),
+            );
+
+        await call();
+        await expect(call()).rejects.toMatchObject({
+            statusCode: 429,
+            legacyCode: 'too_many_requests',
+        });
+
+        expect(alarms).toContainEqual({
+            id: 'driver_rate_limit_hit:rate-limited-iface:run',
+            severity: 'info',
+        });
+    });
+});

src/backend/controllers/drivers/DriverController.test.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.

src/backend/controllers/drivers/DriverController.ts

@@ -1,23 +1,23 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
  *
- * Puter is free software: you can redistribute it and/or modify it under the
- * terms of the GNU Affero General Public License as published by the Free
- * Software Foundation, either version 3 of the License, or (at your option) any
- * later version.
+ * Puter is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
  *
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
- * FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
- * details.
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
  *
  * You should have received a copy of the GNU Affero General Public License
- * along with this program. If not, see
- * [https://www.gnu.org/licenses/](https://www.gnu.org/licenses/).
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
+import { metrics } from '@opentelemetry/api';
 import type { Request, Response } from 'express';
 import { actorUid } from '../../core/actor.js';
 import { Context } from '../../core/context.js';
@@ -45,6 +45,17 @@ import { PuterController } from '../types.js';
 
 type DriverInstance = WithLifecycle & Record<string, unknown>;
 
+// Every driver call is timed here already, for the lifecycle events below.
+// Recording the same number as a histogram makes the per-interface latency
+// distribution available downstream; which interfaces are worth keeping is a
+// collector-side decision, not one made here, so this deliberately records
+// everything and lets the export pipeline drop what it doesn't want.
+const meter = metrics.getMeter('puter-backend');
+const driverCallDuration = meter.createHistogram('driver.call.duration', {
+    description: 'Wall time of a driver method call',
+    unit: 'ms',
+});
+
 const extractUpstreamStatus = (e: {
     status?: number;
     statusCode?: number;
@@ -429,6 +440,11 @@ export class DriverController extends PuterController {
                 () => (fn as (...x: unknown[]) => any).call(driver, args),
             );
         } catch (e) {
+            driverCallDuration.record(Date.now() - startedAt, {
+                driver: ifaceName,
+                'driver.method': method,
+                outcome: 'error',
+            });
             this.clients.event?.emit(
                 `driver.${ifaceName}.${method}.error`,
                 {
@@ -446,6 +462,15 @@ export class DriverController extends PuterController {
             );
             throw translateProviderError(e);
         }
+
+        // Same window the span and the lifecycle events measure: for streamed
+        // results this is stream start, not stream drain. Worth remembering
+        // when reading AI latency — it is time-to-first-token, not total.
+        driverCallDuration.record(Date.now() - startedAt, {
+            driver: ifaceName,
+            'driver.method': method,
+            outcome: 'ok',
+        });
         this.clients.event?.emit(
             `driver.${ifaceName}.${method}.after`,
             {
@@ -533,10 +558,10 @@ export class DriverController extends PuterController {
         // the live instance, so lifecycle hooks / inherited framework
         // methods can never be dispatched.
         this.#callableMethods.set(instance, resolveCallableMethods(instance));
-        // Register each alias pointing at the same instance. Legacy puter-js
-        // calls that pass a provider id in the `driver` slot (e.g. the TTS
-        // module sends `aws-polly` / `openai-tts` / `elevenlabs-tts` instead
-        // of the unified `ai-tts`) resolve here; the handler sets
+        // Register each alias pointing at the same instance. Calls that pass
+        // a provider id in the `driver` slot (e.g. `aws-polly` or
+        // `openai-tts` instead of the unified `ai-tts`, as SDK bundles
+        // predating the unified drivers do) resolve here; the handler sets
         // Context.driverName to the alias so the method can route to the
         // right internal provider.
         for (const alias of meta.aliases) {

src/backend/controllers/fs/FSController.http.test.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.

src/backend/controllers/fs/FSController.test.ts

@@ -1,21 +1,20 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
  *
- * Puter is free software: you can redistribute it and/or modify it under the
- * terms of the GNU Affero General Public License as published by the Free
- * Software Foundation, either version 3 of the License, or (at your option) any
- * later version.
+ * Puter is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
  *
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
- * FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
- * details.
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
  *
  * You should have received a copy of the GNU Affero General Public License
- * along with this program. If not, see
- * [https://www.gnu.org/licenses/](https://www.gnu.org/licenses/).
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
 import type { Request, Response } from 'express';

src/backend/controllers/fs/FSController.ts

@@ -1,21 +1,20 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
  *
- * Puter is free software: you can redistribute it and/or modify it under the
- * terms of the GNU Affero General Public License as published by the Free
- * Software Foundation, either version 3 of the License, or (at your option) any
- * later version.
+ * Puter is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
  *
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
- * FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
- * details.
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
  *
  * You should have received a copy of the GNU Affero General Public License
- * along with this program. If not, see
- * [https://www.gnu.org/licenses/](https://www.gnu.org/licenses/).
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
 import Busboy from 'busboy';
@@ -439,6 +438,11 @@ export class FSController extends PuterController {
             let parseFailure: Error | null = null;
             const uploadPromises: Promise<UploadedBatchWriteItem | null>[] = [];
             const uploadedIndexes = new Set<number>();
+            // Manifest indexes are client-chosen and may skip values (an
+            // ignored `.DS_Store`, or a sparse numbering). `prepareBatchWrites`
+            // re-indexes by array position, so the two spaces have to be
+            // bridged explicitly or file parts get paired with the wrong item.
+            const preparedIndexByManifestIndex = new Map<number, number>();
             let fileOrderIndex = 0;
 
             const failParse = (error: unknown) => {
@@ -549,6 +553,12 @@ export class FSController extends PuterController {
                                 { pathAlreadyNormalized: true },
                             );
 
+                            activeManifestItems.forEach((item, position) => {
+                                preparedIndexByManifestIndex.set(
+                                    item.index,
+                                    position,
+                                );
+                            });
                             preparedBatch =
                                 await this.services.fs.prepareBatchWrites(
                                     userId,
@@ -621,9 +631,13 @@ export class FSController extends PuterController {
                         }
                         uploadedIndexes.add(itemIndex);
 
+                        const preparedIndex =
+                            preparedIndexByManifestIndex.get(itemIndex);
                         const preparedItem =
-                            preparedBatch.itemsByIndex.get(itemIndex);
-                        if (!preparedItem) {
+                            preparedIndex === undefined
+                                ? undefined
+                                : preparedBatch.itemsByIndex.get(preparedIndex);
+                        if (preparedIndex === undefined || !preparedItem) {
                             throw new HttpError(
                                 400,
                                 `Batch write metadata was not found for index ${itemIndex}`,
@@ -641,7 +655,7 @@ export class FSController extends PuterController {
 
                         return await this.services.fs.uploadPreparedBatchItem({
                             preparedBatch,
-                            itemIndex,
+                            itemIndex: preparedIndex,
                             fileContent: stream,
                             uploadTracker,
                         });
@@ -653,6 +667,12 @@ export class FSController extends PuterController {
                     }
                 })();
                 uploadPromises.push(uploadPromise);
+                // Failures are collected with `Promise.allSettled` once
+                // parsing finishes, which is many ticks away — attach an
+                // inert handler now so an immediate rejection (e.g. a file
+                // part arriving before the manifest) isn't reported as an
+                // unhandled rejection in the meantime.
+                void uploadPromise.catch(() => undefined);
             });
 
             const parsingComplete = new Promise<void>((resolve, reject) => {
@@ -662,6 +682,18 @@ export class FSController extends PuterController {
 
             req.pipe(busboy);
             await parsingComplete;
+            // A manifest that failed to parse never sets
+            // `manifestPreparationPromise`, so surface the real reason
+            // (invalid JSON, bad item index, duplicate index → 409) before
+            // falling back to "no manifest was sent at all". Scoped to that
+            // case on purpose: with no prepared batch nothing can have been
+            // uploaded, so there is nothing to clean up. A parse failure that
+            // arrives *after* a manifest was accepted has to fall through to
+            // the cleanup path below, which sweeps objects already in storage.
+            if (parseFailure && !manifestPreparationPromise) {
+                await Promise.allSettled(uploadPromises);
+                throw parseFailure;
+            }
             if (!manifestPreparationPromise) {
                 await Promise.allSettled(uploadPromises);
                 throw new HttpError(400, 'Batch write manifest is required', {
@@ -2059,7 +2091,8 @@ export class FSController extends PuterController {
         // the ActorUser type. Access via the escape hatch until a proper
         // storage-quota mechanism is in place.
         const actorUser = req.actor?.user as
-            Record<string, unknown> | undefined;
+            | Record<string, unknown>
+            | undefined;
 
         const candidates = [
             this.#toStorageCapacityCandidate(actorUser?.free_storage),

src/backend/controllers/fs/LegacyFSController.test.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -928,6 +928,87 @@ describe('LegacyFSController.copy', () => {
         // The entry must still exist — the ghost handler must NOT have run.
         expect(await server.stores.fsEntry.getEntryByPath(src)).not.toBeNull();
     });
+
+    it('surfaces a name collision, then reports and removes the replaced entry on overwrite', async () => {
+        const { actor } = await makeUser();
+        const username = actor.user!.username!;
+        const src = `/${username}/Documents/dup.txt`;
+        const existing = `/${username}/Pictures/dup.txt`;
+        for ( const p of [src, existing] ) {
+            await withActor(actor, () =>
+                controller.touch(
+                    makeReq({ body: { path: p }, actor }),
+                    makeRes().res,
+                ),
+            );
+        }
+
+        // Without overwrite: the v1 conflict contract the GUI's
+        // replace/skip prompts key on.
+        await expect(
+            withActor(actor, () =>
+                controller.copy(
+                    makeReq({
+                        body: {
+                            source: src,
+                            destination: `/${username}/Pictures`,
+                        },
+                        actor,
+                    }),
+                    makeRes().res,
+                ),
+            ),
+        ).rejects.toMatchObject({
+            statusCode: 409,
+            legacyCode: 'item_with_same_name_exists',
+            fields: { entry_name: 'dup.txt' },
+        });
+
+        const replaced = (await server.stores.fsEntry.getEntryByPath(
+            existing,
+        ))!;
+
+        // With overwrite: the replaced entry rides along in the response
+        // (so the caller can drop its row) and item.removed tells every
+        // other client to do the same — without it they keep a ghost row
+        // until the directory is re-listed.
+        const emitSpy = vi.spyOn(server.clients.event, 'emit');
+        let body: Array<{
+            copied: { path: string };
+            overwritten?: { id: string };
+        }>;
+        let removedCall: (typeof emitSpy.mock.calls)[number] | undefined;
+        try {
+            const { res, captured } = makeRes();
+            await withActor(actor, () =>
+                controller.copy(
+                    makeReq({
+                        body: {
+                            source: src,
+                            destination: `/${username}/Pictures`,
+                            overwrite: true,
+                        },
+                        actor,
+                    }),
+                    res,
+                ),
+            );
+            body = captured.body as typeof body;
+            removedCall = emitSpy.mock.calls.find(
+                ([eventName]) => eventName === 'outer.gui.item.removed',
+            );
+        } finally {
+            emitSpy.mockRestore();
+        }
+
+        expect(body[0].copied.path).toBe(existing);
+        expect(body[0].overwritten?.id).toBe(replaced.uuid);
+        expect(removedCall).toBeTruthy();
+        const removedPayload = removedCall?.[1] as {
+            response?: { uid?: string };
+        };
+        expect(removedPayload.response?.uid).toBe(replaced.uuid);
+    });
 });
 
 // ── move ────────────────────────────────────────────────────────────
@@ -1004,6 +1085,89 @@ describe('LegacyFSController.move', () => {
         const body = captured.body as { moved: { path: string } };
         expect(body.moved.path).toBe(`/${username}/Pictures/bar`);
     });
+
+    it('surfaces a name collision, then reports and removes the replaced entry on overwrite', async () => {
+        const { actor } = await makeUser();
+        const username = actor.user!.username!;
+        const src = `/${username}/Documents/clash.txt`;
+        const existing = `/${username}/Pictures/clash.txt`;
+        for ( const p of [src, existing] ) {
+            await withActor(actor, () =>
+                controller.touch(
+                    makeReq({ body: { path: p }, actor }),
+                    makeRes().res,
+                ),
+            );
+        }
+
+        // Without overwrite: the v1 conflict contract the GUI's
+        // replace/skip prompts key on.
+        await expect(
+            withActor(actor, () =>
+                controller.move(
+                    makeReq({
+                        body: {
+                            source: src,
+                            destination: `/${username}/Pictures`,
+                        },
+                        actor,
+                    }),
+                    makeRes().res,
+                ),
+            ),
+        ).rejects.toMatchObject({
+            statusCode: 409,
+            legacyCode: 'item_with_same_name_exists',
+            fields: { entry_name: 'clash.txt' },
+        });
+
+        const replaced = (await server.stores.fsEntry.getEntryByPath(
+            existing,
+        ))!;
+
+        // With overwrite: the replaced entry rides along in the response
+        // (so the caller can drop its row) and item.removed tells every
+        // other client to do the same — without it they keep a ghost row
+        // until the directory is re-listed.
+        const emitSpy = vi.spyOn(server.clients.event, 'emit');
+        let body: {
+            moved: { path: string };
+            old_path: string;
+            overwritten?: { id: string };
+        };
+        let removedCall: (typeof emitSpy.mock.calls)[number] | undefined;
+        try {
+            const { res, captured } = makeRes();
+            await withActor(actor, () =>
+                controller.move(
+                    makeReq({
+                        body: {
+                            source: src,
+                            destination: `/${username}/Pictures`,
+                            overwrite: true,
+                        },
+                        actor,
+                    }),
+                    res,
+                ),
+            );
+            body = captured.body as typeof body;
+            removedCall = emitSpy.mock.calls.find(
+                ([eventName]) => eventName === 'outer.gui.item.removed',
+            );
+        } finally {
+            emitSpy.mockRestore();
+        }
+
+        expect(body.old_path).toBe(src);
+        expect(body.moved.path).toBe(existing);
+        expect(body.overwritten?.id).toBe(replaced.uuid);
+        expect(removedCall).toBeTruthy();
+        const removedPayload = removedCall?.[1] as {
+            response?: { uid?: string };
+        };
+        expect(removedPayload.response?.uid).toBe(replaced.uuid);
+    });
 });
 
 // ── search ──────────────────────────────────────────────────────────
@@ -2743,6 +2907,48 @@ describe('LegacyFSController.updateFsentryThumbnail', () => {
         const body = captured.body as { thumbnail: string };
         expect(typeof body.thumbnail).toBe('string');
     });
+
+    // The write ACL here covers the entry being annotated, not whatever the
+    // thumbnail string points at. A storage pointer stored verbatim is later
+    // presigned (and deleted) by the thumbnails extension using the server's
+    // own credentials, so the owner of one file could name another user's
+    // object — an fs object's key is its fsentry uuid — and have the server
+    // read or destroy it. Only inline image data is accepted.
+    it.each([
+        ['an s3:// pointer', 's3://puter-local/00000000-0000-4000-8000-000000000000'],
+        ['an https URL', 'https://cdn.example.com/x.png'],
+        ['a bare object key', 'thumbnails/whatever'],
+    ])('rejects %s instead of storing it verbatim', async (_label, thumbnail) => {
+        const { actor } = await makeUser();
+        const username = actor.user!.username!;
+        const target = `/${username}/Documents/thumbme3-${uuidv4()}.txt`;
+        await withActor(actor, () =>
+            controller.touch(
+                makeReq({
+                    body: { path: target, set_modified_to_now: true },
+                    actor,
+                }),
+                makeRes().res,
+            ),
+        );
+        const entry = await server.stores.fsEntry.getEntryByPath(target);
+
+        const { res } = makeRes();
+        await expect(
+            withActor(actor, () =>
+                controller.updateFsentryThumbnail(
+                    makeReq({
+                        body: { uid: entry!.uuid, thumbnail },
+                        actor,
+                    }),
+                    res,
+                ),
+            ),
+        ).rejects.toMatchObject({ statusCode: 400 });
+
+        const after = await server.stores.fsEntry.getEntryByUuid(entry!.uuid);
+        expect(after?.thumbnail ?? null).toBeNull();
+    });
 });
 
 // ── GET /get-launch-apps ────────────────────────────────────────────
@@ -2910,4 +3116,24 @@ describe('LegacyFSController GET /get-launch-apps', () => {
         expect(entry?.index_url).toBe('https://dev-owned-domain.example/');
         expect(entry?.privateAccess).toBeUndefined();
     });
+
+    // The rows are fetched in one batched lookup, which returns a map — the
+    // handler has to re-impose the recency order the uid list carries.
+    it('preserves the most-recent-first order of the underlying uid list', async () => {
+        const { actor, userId } = await makeUser();
+        const first = await makeHostedApp(userId, 'unregistered-a');
+        const second = await makeHostedApp(userId, 'unregistered-b');
+        const third = await makeHostedApp(userId, 'unregistered-c');
+
+        await recordOpen(userId, first.uid);
+        await recordOpen(userId, second.uid);
+        await recordOpen(userId, third.uid);
+
+        const recentUids = await server.stores.app.getRecentAppOpens(userId, {
+            limit: 10,
+        });
+        const returned = (await fetchRecent(actor)).map((a) => a.uuid);
+
+        expect(returned).toEqual(recentUids);
+    });
 });

src/backend/controllers/fs/LegacyFSController.ts

@@ -1,21 +1,20 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
  *
- * Puter is free software: you can redistribute it and/or modify it under the
- * terms of the GNU Affero General Public License as published by the Free
- * Software Foundation, either version 3 of the License, or (at your option) any
- * later version.
+ * Puter is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
  *
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
- * FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
- * details.
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
  *
  * You should have received a copy of the GNU Affero General Public License
- * along with this program. If not, see
- * [https://www.gnu.org/licenses/](https://www.gnu.org/licenses/).
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
 import Busboy from 'busboy';
@@ -184,48 +183,60 @@ export class LegacyFSController extends PuterController {
                             ) => Promise<string[]>;
                         }
                     ).getRecentAppOpens?.(userId, { limit: 10 })) ?? [];
-                const apps: unknown[] = [];
-                for (const uid of recentUids) {
-                    const app = await (
-                        this.stores.app as unknown as {
-                            getByUid: (
-                                uid: string,
-                            ) => Promise<Record<string, unknown> | null>;
-                        }
-                    ).getByUid(uid);
-                    if (app) {
-                        // Don't hand out an index_url whose puter-hosted
-                        // backing is gone or reclaimed. The taskbar launches
-                        // recents by name (so AppDriver's guard applies), but
-                        // this list is a launch-metadata producer like any
-                        // other — a future consumer reading index_url
-                        // straight off it shouldn't inherit a stale origin.
-                        const backingGone =
-                            await hostedIndexUrlBackingIsUnavailable({
-                                app,
-                                subdomainStore: this.stores.subdomain,
-                                config: this.config,
-                            }).catch(() => true);
-                        apps.push({
-                            uuid: app.uid,
-                            name: app.name,
-                            title: app.title,
-                            icon: app.icon ?? null,
-                            godmode: Boolean(app.godmode),
-                            maximize_on_start: Boolean(app.maximize_on_start),
-                            index_url: backingGone ? null : app.index_url,
-                            ...(backingGone
-                                ? { privateAccess: buildHostedBackingDenial() }
-                                : {}),
-                            // An app with no owner isn't owned by a Puter user —
-                            // it's an "external" (origin-bootstrapped) app.
-                            external:
-                                app.owner_user_id == null ||
-                                app.owner_user_id === '',
-                        });
+                // One batched read for the rows, then the backing checks
+                // concurrently. Serially awaiting a lookup per uid put ~2
+                // round trips of latency on every desktop boot.
+                const appsByUid = await (
+                    this.stores.app as unknown as {
+                        getByUids: (
+                            uids: string[],
+                        ) => Promise<Map<string, Record<string, unknown>>>;
                     }
-                }
-                recent = apps;
+                ).getByUids(recentUids);
+
+                // `recentUids` is ordered most-recent-first; preserve it.
+                const orderedApps = recentUids
+                    .map((uid) => appsByUid.get(uid))
+                    .filter((app): app is Record<string, unknown> =>
+                        Boolean(app),
+                    );
+
+                // Don't hand out an index_url whose puter-hosted backing is
+                // gone or reclaimed. The taskbar launches recents by name (so
+                // AppDriver's guard applies), but this list is a
+                // launch-metadata producer like any other — a future consumer
+                // reading index_url straight off it shouldn't inherit a stale
+                // origin.
+                const backingGoneFlags = await Promise.all(
+                    orderedApps.map((app) =>
+                        hostedIndexUrlBackingIsUnavailable({
+                            app,
+                            subdomainStore: this.stores.subdomain,
+                            config: this.config,
+                        }).catch(() => true),
+                    ),
+                );
+
+                recent = orderedApps.map((app, index) => {
+                    const backingGone = backingGoneFlags[index];
+                    return {
+                        uuid: app.uid,
+                        name: app.name,
+                        title: app.title,
+                        icon: app.icon ?? null,
+                        godmode: Boolean(app.godmode),
+                        maximize_on_start: Boolean(app.maximize_on_start),
+                        index_url: backingGone ? null : app.index_url,
+                        ...(backingGone
+                            ? { privateAccess: buildHostedBackingDenial() }
+                            : {}),
+                        // An app with no owner isn't owned by a Puter user —
+                        // it's an "external" (origin-bootstrapped) app.
+                        external:
+                            app.owner_user_id == null ||
+                            app.owner_user_id === '',
+                    };
+                });
             }
 
             res.json({ recommended, recent });
@@ -577,26 +588,61 @@ export class LegacyFSController extends PuterController {
             'write',
         );
 
+        // The v1 wire contract reports the entry an overwrite replaced
+        // (`overwritten`) so clients can drop its stale row/icon. The copy
+        // deletes that entry, so resolve it beforehand.
+        const overwriteRequested = getBoolean(body, 'overwrite') ?? false;
+        let overwrittenEntry = null;
+        if (overwriteRequested) {
+            const targetName = getString(body, 'new_name') ?? source.name;
+            const targetPath =
+                destinationParent.path === '/'
+                    ? `/${targetName}`
+                    : `${destinationParent.path}/${targetName}`;
+            overwrittenEntry =
+                await this.stores.fsEntry.getEntryByPath(targetPath);
+        }
+
         const copy = await this.services.fs.copy(userId, {
             source,
             destinationParent,
             newName: getString(body, 'new_name'),
-            overwrite: getBoolean(body, 'overwrite') ?? false,
+            overwrite: overwriteRequested,
             dedupeName: getBoolean(body, 'dedupe_name', 'change_name') ?? false,
         });
         await this.#emitGuiEvent('outer.gui.item.added', copy);
+        // Without this, every other client keeps a ghost row for the
+        // replaced entry until the directory is re-listed.
+        if (overwrittenEntry) {
+            await this.#emitGuiEvent(
+                'outer.gui.item.removed',
+                overwrittenEntry,
+            );
+        }
 
         // Legacy response shape: `[{copied: fsentry, overwritten?}]`.
         // Array is historical — originally supported bulk copy.
-        const copied = await toLegacyEntry(this.clients.event, copy, {
+        const legacyEntryOpts = {
             fsEntryStore: this.stores.fsEntry,
             userStore: this.stores.user as unknown as {
                 getById: (
                     id: number,
                 ) => Promise<Record<string, unknown> | null>;
             },
-        });
-        res.json([{ copied }]);
+        };
+        const copied = await toLegacyEntry(
+            this.clients.event,
+            copy,
+            legacyEntryOpts,
+        );
+        const overwritten = overwrittenEntry
+            ? await toLegacyEntry(
+                  this.clients.event,
+                  overwrittenEntry,
+                  legacyEntryOpts,
+              )
+            : undefined;
+        res.json([{ copied, ...(overwritten ? { overwritten } : {}) }]);
     };
 
     move = async (req: Request, res: Response): Promise<void> => {
@@ -628,11 +674,30 @@ export class LegacyFSController extends PuterController {
             'write',
         );
 
+        // The v1 wire contract reports the entry an overwrite replaced
+        // (`overwritten`) so clients can drop its stale row/icon. The move
+        // deletes that entry, so resolve it beforehand.
+        const overwriteRequested = getBoolean(body, 'overwrite') ?? false;
+        let overwrittenEntry = null;
+        if (overwriteRequested) {
+            const targetName = getString(body, 'new_name') ?? source.name;
+            const targetPath =
+                destinationParent.path === '/'
+                    ? `/${targetName}`
+                    : `${destinationParent.path}/${targetName}`;
+            const existing =
+                await this.stores.fsEntry.getEntryByPath(targetPath);
+            // Moving an entry onto its own path is not an overwrite.
+            if (existing && existing.uuid !== source.uuid) {
+                overwrittenEntry = existing;
+            }
+        }
+
         const moved = await this.services.fs.move(userId, {
             source,
             destinationParent,
             newName: getString(body, 'new_name'),
-            overwrite: getBoolean(body, 'overwrite') ?? false,
+            overwrite: overwriteRequested,
             dedupeName: getBoolean(body, 'dedupe_name', 'change_name') ?? false,
             // Trash/restore rides on this: GUI sends
             // `{ original_name, original_path, trashed_ts }` when moving into
@@ -645,17 +710,41 @@ export class LegacyFSController extends PuterController {
         await this.#emitGuiEvent('outer.gui.item.moved', moved, {
             old_path: oldPath,
         });
+        // Without this, every other client keeps a ghost row for the
+        // replaced entry until the directory is re-listed.
+        if (overwrittenEntry) {
+            await this.#emitGuiEvent(
+                'outer.gui.item.removed',
+                overwrittenEntry,
+            );
+        }
 
-        // Legacy response shape: `{moved: fsentry, old_path}`.
-        const movedEntry = await toLegacyEntry(this.clients.event, moved, {
+        // Legacy response shape: `{moved: fsentry, old_path, overwritten?}`.
+        const legacyEntryOpts = {
             fsEntryStore: this.stores.fsEntry,
             userStore: this.stores.user as unknown as {
                 getById: (
                     id: number,
                 ) => Promise<Record<string, unknown> | null>;
             },
+        };
+        const movedEntry = await toLegacyEntry(
+            this.clients.event,
+            moved,
+            legacyEntryOpts,
+        );
+        const overwritten = overwrittenEntry
+            ? await toLegacyEntry(
+                  this.clients.event,
+                  overwrittenEntry,
+                  legacyEntryOpts,
+              )
+            : undefined;
+        res.json({
+            moved: movedEntry,
+            old_path: oldPath,
+            ...(overwritten ? { overwritten } : {}),
         });
-        res.json({ moved: movedEntry, old_path: oldPath });
     };
 
     delete = async (req: Request, res: Response): Promise<void> => {
@@ -848,6 +937,14 @@ export class LegacyFSController extends PuterController {
             throw new HttpError(400, 'Missing `thumbnail`', {
                 legacyCode: 'bad_request',
             });
+        // Only inline image data. Clients generate the thumbnail themselves
+        // and the thumbnails extension is what turns it into a storage
+        // pointer; accepting a pointer here would let a caller name an object
+        // the server would then sign reads of, and delete, on their behalf.
+        if (!thumbnail.startsWith('data:'))
+            throw new HttpError(400, '`thumbnail` must be a data: URL', {
+                legacyCode: 'bad_request',
+            });
 
         const entry = await this.stores.fsEntry.getEntryByUuid(uid);
         if (!entry || !entry.path)

src/backend/controllers/fs/costs.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.

src/backend/controllers/fs/legacyFsHelpers.test.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -18,13 +18,24 @@
  */
 
 import { describe, expect, it } from 'vitest';
-import { loadLegacyAssociatedApps } from './legacyFsHelpers.js';
+import {
+    asRecord,
+    fsEntryMimeType,
+    getBoolean,
+    getString,
+    loadLegacyAssociatedApps,
+    signEntryThumbnail,
+    signingConfigFromAppConfig,
+    toLegacyEntry,
+} from './legacyFsHelpers.js';
 import type { FSEntry } from '../../stores/fs/FSEntry.js';
 
 const entryWithApp = (associatedAppId: number): FSEntry =>
     ({ associatedAppId }) as unknown as FSEntry;
 
-const appRow = (overrides: Record<string, unknown>): Record<string, unknown> => ({
+const appRow = (
+    overrides: Record<string, unknown>,
+): Record<string, unknown> => ({
     id: 1,
     uid: 'app-1',
     owner_user_id: 99,
@@ -100,3 +111,336 @@ describe('loadLegacyAssociatedApps associated_app redaction', () => {
         expect(app.godmode).toBe(0);
     });
 });
+
+describe('asRecord', () => {
+    it.each([
+        ['null', null],
+        ['undefined', undefined],
+        ['a number', 42],
+        ['a string', 'nope'],
+        ['an array', [1, 2]],
+    ])('returns an empty record for %s', (_label, value) => {
+        expect(asRecord(value)).toEqual({});
+    });
+
+    it('passes an object through unchanged', () => {
+        const source = { a: 1 };
+        expect(asRecord(source)).toBe(source);
+    });
+});
+
+describe('getString', () => {
+    it('returns the first non-empty string among the candidate keys', () => {
+        expect(getString({ a: '', b: 'second' }, 'a', 'b')).toBe('second');
+    });
+
+    it('ignores non-string values', () => {
+        expect(getString({ a: 5, b: true }, 'a', 'b')).toBeUndefined();
+    });
+
+    it('returns undefined when no key matches', () => {
+        expect(getString({}, 'missing')).toBeUndefined();
+    });
+});
+
+describe('getBoolean', () => {
+    it.each([
+        [true, true],
+        [false, false],
+        [1, true],
+        [0, false],
+        ['1', true],
+        ['TRUE', true],
+        [' yes ', true],
+        ['on', true],
+        ['0', false],
+        ['false', false],
+        ['no', false],
+        ['off', false],
+    ])('coerces %o to %s', (input, expected) => {
+        expect(getBoolean({ flag: input }, 'flag')).toBe(expected);
+    });
+
+    it.each([[2], ['maybe'], [null], [{}]])(
+        'returns undefined for the uncoercible value %o',
+        (input) => {
+            expect(getBoolean({ flag: input }, 'flag')).toBeUndefined();
+        },
+    );
+
+    it('falls through to a later alias when the first key is absent', () => {
+        expect(
+            getBoolean({ change_name: true }, 'dedupe_name', 'change_name'),
+        ).toBe(true);
+    });
+});
+
+describe('fsEntryMimeType', () => {
+    it('reports directories as "folder"', () => {
+        expect(fsEntryMimeType({ isDir: true, name: 'Documents' })).toBe(
+            'folder',
+        );
+    });
+
+    it('derives a MIME type with charset from the file name', () => {
+        expect(fsEntryMimeType({ isDir: false, name: 'a.png' })).toBe(
+            'image/png',
+        );
+        expect(fsEntryMimeType({ isDir: false, name: 'a.txt' })).toContain(
+            'text/plain',
+        );
+    });
+
+    it('returns null for an extensionless name', () => {
+        expect(fsEntryMimeType({ isDir: false, name: 'LICENSE' })).toBeNull();
+    });
+});
+
+describe('signEntryThumbnail', () => {
+    it('returns the input untouched when there is no event client', async () => {
+        expect(
+            await signEntryThumbnail(undefined, 'uuid-1', 's3://bucket/key'),
+        ).toBe('s3://bucket/key');
+    });
+
+    it('normalizes a missing thumbnail to null', async () => {
+        expect(await signEntryThumbnail(undefined, 'uuid-1', null)).toBeNull();
+    });
+
+    it('returns the URL the listener rewrote onto the payload', async () => {
+        const eventClient = {
+            emitAndWait: async (
+                _key: string,
+                payload: { thumbnail: string },
+            ) => {
+                payload.thumbnail = 'https://signed.test/thumb.png';
+            },
+        } as never;
+        expect(
+            await signEntryThumbnail(eventClient, 'uuid-1', 's3://bucket/key'),
+        ).toBe('https://signed.test/thumb.png');
+    });
+
+    it('returns null when the listener blanks the thumbnail', async () => {
+        const eventClient = {
+            emitAndWait: async (
+                _key: string,
+                payload: { thumbnail: string },
+            ) => {
+                payload.thumbnail = '';
+            },
+        } as never;
+        expect(
+            await signEntryThumbnail(eventClient, 'uuid-1', 's3://bucket/key'),
+        ).toBeNull();
+    });
+
+    it('keeps the original value when the listener throws', async () => {
+        const eventClient = {
+            emitAndWait: async () => {
+                throw new Error('extension down');
+            },
+        } as never;
+        expect(
+            await signEntryThumbnail(eventClient, 'uuid-1', 's3://bucket/key'),
+        ).toBe('s3://bucket/key');
+    });
+});
+
+describe('signingConfigFromAppConfig', () => {
+    it('returns the secret and api base url when both are set', () => {
+        expect(
+            signingConfigFromAppConfig({
+                url_signature_secret: 's3cret',
+                api_base_url: 'https://api.test',
+            } as never),
+        ).toEqual({ secret: 's3cret', apiBaseUrl: 'https://api.test' });
+    });
+
+    it('fails loudly when the signing secret is missing', () => {
+        expect(() =>
+            signingConfigFromAppConfig({
+                api_base_url: 'https://api.test',
+            } as never),
+        ).toThrowError(/url_signature_secret not set/);
+    });
+
+    it('fails loudly when the api base url is missing', () => {
+        expect(() =>
+            signingConfigFromAppConfig({
+                url_signature_secret: 's3cret',
+            } as never),
+        ).toThrowError(/api_base_url not set/);
+    });
+});
+
+describe('toLegacyEntry', () => {
+    const baseEntry = (overrides: Partial<FSEntry> = {}): FSEntry =>
+        ({
+            uuid: 'uuid-1',
+            parentUid: 'parent-1',
+            path: '/alice/Documents/report.pdf',
+            name: 'report.pdf',
+            isDir: false,
+            isShortcut: false,
+            shortcutTo: null,
+            isSymlink: false,
+            symlinkPath: null,
+            isPublic: false,
+            thumbnail: null,
+            immutable: false,
+            metadata: null,
+            modified: 1000,
+            created: 900,
+            accessed: 950,
+            size: 12,
+            layout: null,
+            subdomains: [],
+            workers: [],
+            suggestedApps: [],
+            associatedAppId: null,
+            userId: 7,
+            ...overrides,
+        }) as unknown as FSEntry;
+
+    it('produces the snake_case v1 shape for a file', async () => {
+        const shaped = await toLegacyEntry(undefined, baseEntry());
+        expect(shaped).toMatchObject({
+            id: 'uuid-1',
+            uid: 'uuid-1',
+            uuid: 'uuid-1',
+            parent_id: 'parent-1',
+            parent_uid: 'parent-1',
+            dirname: '/alice/Documents',
+            dirpath: '/alice/Documents',
+            is_dir: false,
+            is_shortcut: 0,
+            is_symlink: 0,
+            has_website: false,
+            is_empty: false,
+            associated_app: null,
+            appdata_app: undefined,
+        });
+        expect(shaped.type).toContain('application/pdf');
+    });
+
+    it('names the owning app for an AppData path', async () => {
+        const shaped = await toLegacyEntry(
+            undefined,
+            baseEntry({ path: '/alice/AppData/app-42/state.json' }),
+        );
+        expect(shaped.appdata_app).toBe('app-42');
+    });
+
+    it('reports has_website when the entry carries a subdomain', async () => {
+        const shaped = await toLegacyEntry(
+            undefined,
+            baseEntry({
+                subdomains: [{ subdomain: 'site' }] as never,
+            }),
+        );
+        expect(shaped.has_website).toBe(true);
+    });
+
+    it('probes for children to set is_empty on a directory', async () => {
+        const fsEntryStore = {
+            listChildren: async () => [{ uuid: 'child' }],
+        } as never;
+        const shaped = await toLegacyEntry(
+            undefined,
+            baseEntry({ isDir: true, name: 'Documents' }),
+            { fsEntryStore },
+        );
+        expect(shaped.is_empty).toBe(false);
+        expect(shaped.type).toBe('folder');
+    });
+
+    it('treats a failed child probe as non-empty rather than throwing', async () => {
+        const fsEntryStore = {
+            listChildren: async () => {
+                throw new Error('db down');
+            },
+        } as never;
+        const shaped = await toLegacyEntry(
+            undefined,
+            baseEntry({ isDir: true }),
+            { fsEntryStore },
+        );
+        expect(shaped.is_empty).toBe(false);
+    });
+
+    it('hydrates the owner as a username-only object', async () => {
+        const userStore = {
+            getById: async () => ({ username: 'alice', email: '[email protected]' }),
+        };
+        const shaped = await toLegacyEntry(undefined, baseEntry(), {
+            userStore,
+        });
+        // Username only — the rest of the user row must not ride along.
+        expect(shaped.owner).toEqual({ username: 'alice' });
+    });
+
+    it('omits the owner when the lookup fails', async () => {
+        const userStore = {
+            getById: async () => {
+                throw new Error('db down');
+            },
+        };
+        const shaped = await toLegacyEntry(undefined, baseEntry(), {
+            userStore,
+        });
+        expect(shaped).not.toHaveProperty('owner');
+    });
+
+    it('embeds associated_app from the prebuilt map', async () => {
+        const appsById = new Map([[3, { uid: 'app-3', name: 'Editor' }]]);
+        const shaped = await toLegacyEntry(
+            undefined,
+            baseEntry({ associatedAppId: 3 }),
+            { appsById },
+        );
+        expect(shaped.associated_app).toEqual({ uid: 'app-3', name: 'Editor' });
+    });
+
+    it('emits a null associated_app when the id is not in the map', async () => {
+        const shaped = await toLegacyEntry(
+            undefined,
+            baseEntry({ associatedAppId: 9 }),
+            { appsById: new Map() },
+        );
+        expect(shaped.associated_app).toBeNull();
+    });
+});
+
+describe('loadLegacyAssociatedApps short-circuit', () => {
+    it('makes no store call when no entry carries an app id', async () => {
+        let calls = 0;
+        const store = {
+            getByIds: async () => {
+                calls += 1;
+                return new Map();
+            },
+        };
+        const out = await loadLegacyAssociatedApps(store, [
+            { associatedAppId: null } as unknown as FSEntry,
+        ]);
+        expect(out.size).toBe(0);
+        expect(calls).toBe(0);
+    });
+
+    it('dedupes repeated app ids into a single lookup', async () => {
+        const seen: number[][] = [];
+        const store = {
+            getByIds: async (ids: number[]) => {
+                seen.push(ids);
+                return new Map(ids.map((id) => [id, appRow({ id })]));
+            },
+        };
+        await loadLegacyAssociatedApps(store, [
+            entryWithApp(4),
+            entryWithApp(4),
+            entryWithApp(5),
+        ]);
+        expect(seen).toEqual([[4, 5]]);
+    });
+});

src/backend/controllers/fs/legacyFsHelpers.ts

@@ -1,21 +1,20 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
  *
- * Puter is free software: you can redistribute it and/or modify it under the
- * terms of the GNU Affero General Public License as published by the Free
- * Software Foundation, either version 3 of the License, or (at your option) any
- * later version.
+ * Puter is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
  *
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
- * FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
- * details.
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
  *
  * You should have received a copy of the GNU Affero General Public License
- * along with this program. If not, see
- * [https://www.gnu.org/licenses/](https://www.gnu.org/licenses/).
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
 import { posix as pathPosix } from 'node:path';

src/backend/controllers/fs/requestTypes.ts

@@ -1,21 +1,20 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
  *
- * Puter is free software: you can redistribute it and/or modify it under the
- * terms of the GNU Affero General Public License as published by the Free
- * Software Foundation, either version 3 of the License, or (at your option) any
- * later version.
+ * Puter is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
  *
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
- * FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
- * details.
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
  *
  * You should have received a copy of the GNU Affero General Public License
- * along with this program. If not, see
- * [https://www.gnu.org/licenses/](https://www.gnu.org/licenses/).
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
 import type { Readable } from 'node:stream';

src/backend/controllers/fs/types.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.

src/backend/controllers/homepage/HomepageController.test.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -314,6 +314,76 @@ describe('HomepageController GET /app/:name', () => {
         expect(html).not.toContain(secretUrl);
         expect(html).not.toContain('owner_user_id');
     });
+
+    it('serves the same app shell under /desktop/app/:name', async () => {
+        const { userId } = await makeUser();
+        const name = `desk-${Math.random().toString(36).slice(2, 10)}`;
+        await server.stores.app.create(
+            {
+                name,
+                title: 'Desktop App',
+                description: 'opens on the desktop instead of the dashboard',
+                index_url: `https://example.com/${name}/`,
+                approved_for_listing: 1,
+            },
+            { ownerUserId: userId },
+        );
+
+        const { res, captured } = makeRes();
+        await callRoute(
+            'get',
+            '/desktop/app/:name',
+            makeReq({ params: { name }, path: `/desktop/app/${name}` }),
+            res,
+        );
+
+        expect(captured.statusCode).toBe(200);
+        const html = String(captured.body);
+        expect(html).toMatch(/<!DOCTYPE html>/i);
+        expect(html).toContain('Desktop App');
+    });
+
+    it('returns 404 under /desktop/app/:name when the app is unknown', async () => {
+        const { res, captured } = makeRes();
+        await callRoute(
+            'get',
+            '/desktop/app/:name',
+            makeReq({
+                params: { name: 'no-such-app' },
+                path: '/desktop/app/no-such-app',
+            }),
+            res,
+        );
+        expect(captured.statusCode).toBe(404);
+        expect(String(captured.body)).toMatch(/<!DOCTYPE html>/i);
+    });
+
+    it('omits index_url even for a public app — the shell is not the launch authority', async () => {
+        const { userId } = await makeUser();
+        const name = `pub-${Math.random().toString(36).slice(2, 10)}`;
+        const indexUrl = `https://public-${name}.example.com/`;
+        await server.stores.app.create(
+            { name, title: 'Public App', index_url: indexUrl },
+            { ownerUserId: userId },
+        );
+
+        const { res, captured } = makeRes();
+        await callRoute(
+            'get',
+            '/app/:name',
+            makeReq({ params: { name }, path: `/app/${name}` }),
+            res,
+        );
+
+        expect(captured.statusCode).toBe(200);
+        const html = String(captured.body);
+        expect(html).toContain('Public App');
+        // The GUI re-reads the app through the driver before launching, which
+        // is where the entitlement gate and hosted-backing guard run. Baking
+        // a launch URL into server-rendered HTML buys nothing and costs the
+        // lookups those guards require.
+        expect(html).not.toContain(indexUrl);
+    });
 });
 
 // ── /show/* ─────────────────────────────────────────────────────────

src/backend/controllers/homepage/HomepageController.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -20,6 +20,7 @@
 import express from 'express';
 import path from 'node:path';
 import { PuterController } from '../types.js';
+import { toAppShellView } from '../../util/appShellView.js';
 import type { PuterRouter } from '../../core/http/PuterRouter';
 import type {
     PuterHomepageService,
@@ -32,8 +33,8 @@ import type {
  * under `<gui_assets_root>/src` for non-dist/src paths (images, fonts, lib
  * files referenced from the shell).
  *
- * All root-subdomain-only. Registered last in the controller list so the
- * static catch-all doesn't shadow specific API routes.
+ * All root-subdomain-only. Registered last in the controller list so the static
+ * catch-all doesn't shadow specific API routes.
  */
 export class HomepageController extends PuterController {
     registerRoutes(router: PuterRouter) {
@@ -90,8 +91,14 @@ export class HomepageController extends PuterController {
         router.get('/@:username', {}, (req, res) => sendShell(req, res));
 
         // -- /app/:name - app metadata baked into the shell ----------
+        // `/desktop/app/:name` is the same landing booted on the desktop
+        // instead of the dashboard; the GUI strips the prefix and treats the
+        // rest of the path identically, so both render the same shell.
 
-        router.get('/app/:name', {}, async (req, res) => {
+        const sendAppShell = async (
+            req: express.Request,
+            res: express.Response,
+        ) => {
             const name = String(req.params.name ?? '');
             const app = name ? await this.stores.app.getByName(name) : null;
 
@@ -102,17 +109,11 @@ export class HomepageController extends PuterController {
                         : (app.metadata as Record<string, unknown> | null)) ??
                     {};
                 // Never bake the raw store row into the shell — it exposes
-                // `index_url`, `owner_user_id`, and admin flags. Run it
-                // through the authoritative serializer, which redacts to a
-                // safe field subset and drops `index_url` for a private app
-                // this actor (possibly anonymous) isn't entitled to.
-                const actor =
-                    (req as express.Request & { actor?: unknown }).actor ??
-                    null;
-                const clientApp = await this.drivers.apps.toClientView(
-                    app,
-                    actor,
-                );
+                // `index_url`, `owner_user_id`, and moderation flags. The
+                // shell only needs a preview; the GUI re-reads the app
+                // through the apps driver before launching, and that read is
+                // where the entitlement gate and hosted-backing guard run.
+                const clientApp = toAppShellView(app);
                 await sendShell(req, res, {
                     title: String(app.title ?? name),
                     description: String(app.description ?? ''),
@@ -135,7 +136,10 @@ export class HomepageController extends PuterController {
                     ? name.charAt(0).toUpperCase() + name.slice(1)
                     : 'Puter',
             });
-        });
+        };
+
+        router.get('/app/:name', {}, sendAppShell);
+        router.get('/desktop/app/:name', {}, sendAppShell);
 
         // -- /show/* - launch explorer with the requested file path --
 

src/backend/controllers/hosting/HostingController.js

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -22,10 +22,10 @@ import { PuterController } from '../types.js';
 
 /**
  * Site hosting endpoints. Listing and create/update are not exposed as
- * controller routes — clients use the `puter-subdomains` driver
- * (select / create / update / read) so they get the v1-shape with
- * uuids and nested objects (no raw mysql ids). Only `/delete-site`
- * lives here because v1 also exposed it as a top-level POST.
+ * controller routes — clients use the `puter-subdomains` driver (select /
+ * create / update / read) so they get the v1-shape with uuids and nested
+ * objects (no raw mysql ids). Only `/delete-site` lives here because v1 also
+ * exposed it as a top-level POST.
  */
 export class HostingController extends PuterController {
     constructor(config, clients, stores, services) {

src/backend/controllers/hosting/HostingController.test.js

@@ -0,0 +1,184 @@
+/**
+ * Copyright (C) 2024-present Puter Technologies Inc.
+ *
+ * This file is part of Puter.
+ *
+ * Puter is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+import { v4 as uuidv4 } from 'uuid';
+import { afterAll, beforeAll, describe, expect, it, vi } from 'vitest';
+import { PuterRouter } from '../../core/http/PuterRouter.js';
+import { setupTestServer } from '../../testUtil.js';
+
+// `/delete-site` is the only hosting route exposed as a controller endpoint
+// (everything else goes through the `puter-subdomains` driver), and it is an
+// ownership-gated destructive operation — so the interesting cases are the
+// refusals.
+
+let server;
+let deleteSite;
+
+beforeAll(async () => {
+    server = await setupTestServer();
+    const router = new PuterRouter();
+    server.controllers.hosting.registerRoutes(router);
+    deleteSite = router.routes.find(
+        (route) => route.path === '/delete-site',
+    ).handler;
+});
+
+afterAll(async () => {
+    await server?.shutdown();
+});
+
+const makeUser = async () => {
+    const username = `host-${Math.random().toString(36).slice(2, 10)}`;
+    const created = await server.stores.user.create({
+        username,
+        uuid: uuidv4(),
+        password: null,
+        email: `${username}@test.local`,
+        requires_email_confirmation: false,
+    });
+    return {
+        userId: created.id,
+        username,
+        actor: { user: { id: created.id, uuid: created.uuid, username } },
+    };
+};
+
+const makeSite = async (userId) => {
+    const subdomain = `site-${Math.random().toString(36).slice(2, 10)}`;
+    return server.stores.subdomain.create({ userId, subdomain });
+};
+
+const makeReq = (init) => ({
+    body: init.body,
+    query: {},
+    headers: {},
+    actor: init.actor,
+});
+
+const makeRes = () => {
+    const captured = { statusCode: 200, body: undefined };
+    const res = {
+        json: vi.fn((value) => {
+            captured.body = value;
+            return res;
+        }),
+        status: vi.fn((code) => {
+            captured.statusCode = code;
+            return res;
+        }),
+    };
+    return { res, captured };
+};
+
+describe('HostingController /delete-site', () => {
+    it('rejects a missing site_uuid', async () => {
+        const { actor } = await makeUser();
+        await expect(
+            deleteSite(makeReq({ body: {}, actor }), makeRes().res),
+        ).rejects.toMatchObject({
+            statusCode: 400,
+            legacyCode: 'bad_request',
+        });
+    });
+
+    it('rejects a non-string site_uuid', async () => {
+        const { actor } = await makeUser();
+        await expect(
+            deleteSite(
+                makeReq({ body: { site_uuid: 42 }, actor }),
+                makeRes().res,
+            ),
+        ).rejects.toMatchObject({ statusCode: 400 });
+    });
+
+    it('rejects a missing body entirely', async () => {
+        const { actor } = await makeUser();
+        await expect(
+            deleteSite(makeReq({ body: undefined, actor }), makeRes().res),
+        ).rejects.toMatchObject({ statusCode: 400 });
+    });
+
+    it('404s a site uuid that does not exist', async () => {
+        const { actor } = await makeUser();
+        await expect(
+            deleteSite(
+                makeReq({ body: { site_uuid: uuidv4() }, actor }),
+                makeRes().res,
+            ),
+        ).rejects.toMatchObject({
+            statusCode: 404,
+            legacyCode: 'not_found',
+        });
+    });
+
+    it("404s another user's site rather than revealing it exists", async () => {
+        const owner = await makeUser();
+        const stranger = await makeUser();
+        const site = await makeSite(owner.userId);
+
+        await expect(
+            deleteSite(
+                makeReq({
+                    body: { site_uuid: site.uuid },
+                    actor: stranger.actor,
+                }),
+                makeRes().res,
+            ),
+        ).rejects.toMatchObject({ statusCode: 404 });
+        // Still there.
+        expect(
+            await server.stores.subdomain.getByUuid(site.uuid),
+        ).not.toBeNull();
+    });
+
+    it('refuses to delete a protected subdomain', async () => {
+        const { userId, actor } = await makeUser();
+        const site = await makeSite(userId);
+        await server.clients.db.write(
+            'UPDATE `subdomains` SET `protected` = ? WHERE `uuid` = ?',
+            [1, site.uuid],
+        );
+
+        await expect(
+            deleteSite(
+                makeReq({ body: { site_uuid: site.uuid }, actor }),
+                makeRes().res,
+            ),
+        ).rejects.toMatchObject({
+            statusCode: 403,
+            legacyCode: 'forbidden',
+        });
+        expect(
+            await server.stores.subdomain.getByUuid(site.uuid),
+        ).not.toBeNull();
+    });
+
+    it('deletes the caller-owned site and answers with an empty object', async () => {
+        const { userId, actor } = await makeUser();
+        const site = await makeSite(userId);
+
+        const { res, captured } = makeRes();
+        await deleteSite(
+            makeReq({ body: { site_uuid: site.uuid }, actor }),
+            res,
+        );
+        expect(captured.body).toEqual({});
+        expect(await server.stores.subdomain.getByUuid(site.uuid)).toBeNull();
+    });
+});

src/backend/controllers/index.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.

src/backend/controllers/notification/NotificationController.test.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.

src/backend/controllers/notification/NotificationController.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -24,19 +24,18 @@ import type { NotificationService } from '../../services/notification/Notificati
 import { PuterController } from '../types.js';
 
 /**
- * GUI-facing notification endpoints. These supplement the
- * `puter-notifications` driver (which handles CRUD via `/drivers/call`)
- * with two small mutation routes that the puter desktop client calls
- * directly.
+ * GUI-facing notification endpoints. These supplement the `puter-notifications`
+ * driver (which handles CRUD via `/drivers/call`) with two small mutation
+ * routes that the puter desktop client calls directly.
  *
- * Both routes emit `outer.gui.notif.ack` via the NotificationService
- * so other open tabs for the same user see the state change immediately.
+ * Both routes emit `outer.gui.notif.ack` via the NotificationService so other
+ * open tabs for the same user see the state change immediately.
  */
 @Controller('/notif')
 export class NotificationController extends PuterController {
     /**
-     * POST /notif/mark-ack — user dismissed a notification.
-     * Sets `acknowledged` timestamp; pushes ack event to sockets.
+     * POST /notif/mark-ack — user dismissed a notification. Sets `acknowledged`
+     * timestamp; pushes ack event to sockets.
      */
     @Post('/mark-ack', {
         subdomain: 'api',
@@ -78,8 +77,8 @@ export class NotificationController extends PuterController {
     }
 
     /**
-     * POST /notif/mark-read — user saw a notification.
-     * Sets `shown` timestamp; pushes ack event to sockets.
+     * POST /notif/mark-read — user saw a notification. Sets `shown` timestamp;
+     * pushes ack event to sockets.
      */
     @Post('/mark-read', {
         subdomain: 'api',

src/backend/controllers/oidc/OIDCController.test.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -27,6 +27,7 @@ import {
     it,
     vi,
 } from 'vitest';
+import jwt from 'jsonwebtoken';
 import { v4 as uuidv4 } from 'uuid';
 import { runWithContext } from '../../core/context.js';
 import { PuterRouter } from '../../core/http/PuterRouter.js';
@@ -329,6 +330,77 @@ describe('OIDCController GET /auth/oidc/:provider/start', () => {
         expect(decoded).toMatchObject({ referrer: 'http://ref.test' });
     });
 
+    it('bakes a whitelisted return_to (/app/<name>) into the state redirect_uri', async () => {
+        const { res, captured } = makeRes();
+        await callRoute(
+            'get',
+            '/auth/oidc/:provider/start',
+            makeReq({
+                params: { provider: 'custom' },
+                query: { return_to: '/app/my-App_2' },
+            }),
+            res,
+        );
+        const state = new URL(captured.redirectUrl ?? '').searchParams.get(
+            'state',
+        );
+        const decoded = oidc().verifyState(state!);
+        expect(String(decoded?.redirect_uri)).toBe(
+            `${TEST_ORIGIN}/app/my-App_2`,
+        );
+    });
+
+    it('bakes a whitelisted desktop app landing (/desktop/app/<name>) into the state redirect_uri', async () => {
+        const { res, captured } = makeRes();
+        await callRoute(
+            'get',
+            '/auth/oidc/:provider/start',
+            makeReq({
+                params: { provider: 'custom' },
+                query: { return_to: '/desktop/app/my-App_2' },
+            }),
+            res,
+        );
+        const state = new URL(captured.redirectUrl ?? '').searchParams.get(
+            'state',
+        );
+        const decoded = oidc().verifyState(state!);
+        expect(String(decoded?.redirect_uri)).toBe(
+            `${TEST_ORIGIN}/desktop/app/my-App_2`,
+        );
+    });
+
+    it('ignores a non-whitelisted return_to', async () => {
+        const bad_values = [
+            '/app/evil/extra',
+            '/app/',
+            '/app/name?x=1',
+            '//evil.test',
+            '/settings',
+            `/app/${'a'.repeat(101)}`,
+            '/desktop/app/evil/extra',
+            '/desktop/app/',
+            '/dashboard/app/name',
+        ];
+        for (const return_to of bad_values) {
+            const { res, captured } = makeRes();
+            await callRoute(
+                'get',
+                '/auth/oidc/:provider/start',
+                makeReq({
+                    params: { provider: 'custom' },
+                    query: { return_to },
+                }),
+                res,
+            );
+            const state = new URL(
+                captured.redirectUrl ?? '',
+            ).searchParams.get('state');
+            const decoded = oidc().verifyState(state!);
+            expect(String(decoded?.redirect_uri)).toBe(TEST_ORIGIN);
+        }
+    });
+
     it('signs revalidate-flow state with user_uuid + flow=revalidate', async () => {
         const userUuid = uuidv4();
         const { res, captured } = makeRes();
@@ -621,6 +693,76 @@ describe('OIDCController login callback', () => {
         expect(captured.cookies).toHaveLength(0);
     });
 
+    it('redirects back to an /app/<name> landing after sign-in', async () => {
+        const state = oidc().signState({
+            provider: 'custom',
+            redirect_uri: `${TEST_ORIGIN}/app/some-app`,
+        });
+        vi.spyOn(oidc(), 'exchangeCodeForTokens').mockResolvedValue({
+            access_token: 'access',
+            id_token: 'id',
+        } as never);
+        vi.spyOn(oidc(), 'getUserInfo').mockResolvedValue({
+            sub: `sub-${Math.random().toString(36).slice(2, 8)}`,
+            email: `oidc-${Math.random().toString(36).slice(2, 8)}@test.local`,
+            email_verified: true,
+        } as never);
+
+        const { res, captured } = makeRes();
+        await callRoute(
+            'get',
+            '/auth/oidc/callback/login',
+            makeReq({ query: { code: 'c', state } }),
+            res,
+        );
+        expect(captured.cookies).toHaveLength(1);
+        expect(captured.redirectUrl).toBe(`${TEST_ORIGIN}/app/some-app`);
+    });
+
+    it('keeps an /app/<name> landing in the error redirect (suspended user)', async () => {
+        const sub = `sub-${Math.random().toString(36).slice(2, 8)}`;
+        const email = `sus-app-${Math.random().toString(36).slice(2, 8)}@test.local`;
+        const created = await runWithContext(
+            { req: makeReq({}) },
+            () =>
+                oidc().createUserFromOIDC('custom', {
+                    sub,
+                    email,
+                    email_verified: true,
+                }),
+        );
+        expect(created.success).toBe(true);
+        await server.stores.user.update(created.user!.id, { suspended: 1 });
+
+        const state = oidc().signState({
+            provider: 'custom',
+            redirect_uri: `${TEST_ORIGIN}/app/some-app`,
+        });
+        vi.spyOn(oidc(), 'exchangeCodeForTokens').mockResolvedValue({
+            access_token: 'access',
+            id_token: 'id',
+        } as never);
+        vi.spyOn(oidc(), 'getUserInfo').mockResolvedValue({
+            sub,
+            email,
+            email_verified: true,
+        } as never);
+
+        const { res, captured } = makeRes();
+        await callRoute(
+            'get',
+            '/auth/oidc/callback/login',
+            makeReq({ query: { code: 'c', state } }),
+            res,
+        );
+        expect(captured.redirectStatus).toBe(302);
+        const url = new URL(captured.redirectUrl ?? '');
+        expect(url.pathname).toBe('/app/some-app');
+        expect(url.searchParams.get('auth_error')).toBe('1');
+        expect(url.searchParams.get('action')).toBe('login');
+        expect(captured.cookies).toHaveLength(0);
+    });
+
     it('appends oidc_login=true and uses popup-style URL when state is from a popup flow', async () => {
         const sub = `sub-${Math.random().toString(36).slice(2, 8)}`;
         const email = `oidc-${Math.random().toString(36).slice(2, 8)}@test.local`;
@@ -903,6 +1045,39 @@ describe('OIDCController signup veto (abuse harness)', () => {
         expect(captured.redirectUrl).toContain('message=signup_blocked');
         expect(captured.redirectUrl).not.toContain('request_code');
     });
+
+    it('keeps a veto legible when the listener stamps its own code', async () => {
+        const email = `veto-${Math.random().toString(36).slice(2, 8)}@test.local`;
+        signupValidateOverride = (data) => {
+            if (data.email !== email) return;
+            data.allow = false;
+            data.code = 'email_reputation_too_low';
+            data.trail_id = 'trail-custom-code';
+        };
+        stubIdp(`sub-${Math.random().toString(36).slice(2, 8)}`, email);
+
+        const state = oidc().signState({
+            provider: 'custom',
+            redirect_uri: TEST_ORIGIN + '/',
+        });
+        const { res, captured } = makeRes();
+        await callRoute(
+            'get',
+            '/auth/oidc/callback/signup',
+            makeReq({ query: { code: 'c', state } }),
+            res,
+        );
+
+        // A listener code isn't one of the display codes, but the failure
+        // is still a blocked signup — collapsing it to `unauthorized`
+        // would tell the user sign-in broke and bury the Request Code
+        // support needs.
+        expect(captured.redirectUrl).toContain('message=signup_blocked');
+        expect(captured.redirectUrl).not.toContain('message=unauthorized');
+        expect(captured.redirectUrl).toContain(
+            'request_code=trail-custom-code',
+        );
+    });
 });
 
 describe('OIDCController browser binding', () => {
@@ -1476,3 +1651,98 @@ describe('OIDCController GET /auth/revalidate-done', () => {
         expect(body).toContain(JSON.stringify(TEST_ORIGIN));
     });
 });
+
+// ── POST /auth/oidc/verify-popup-return ─────────────────────────────
+
+/**
+ * The proof exists because the popup return leg states two things the popup
+ * cannot check — the opener's origin and that a login completed — and a URL
+ * built from a verified `state` is byte-identical to one anybody can type.
+ * The opener's origin picks the app a token is minted for, so it has to be
+ * attested rather than read.
+ */
+describe('OIDCController POST /auth/oidc/verify-popup-return', () => {
+    const redeem = async (opener_state: unknown) => {
+        const { res, captured } = makeRes();
+        await callRoute(
+            'post',
+            '/auth/oidc/verify-popup-return',
+            makeReq({ body: { opener_state } }),
+            res,
+        );
+        return captured;
+    };
+
+    it('hands back what a genuine proof attests', async () => {
+        const proof = server.services.oidc.signPopupReturn({
+            opener_origin: 'https://opener.test',
+            msg_id: '77',
+            oidc_login: true,
+        });
+        const captured = await redeem(proof);
+        expect(captured.body).toEqual({
+            opener_origin: 'https://opener.test',
+            msg_id: '77',
+            oidc_login: true,
+        });
+    });
+
+    it('rejects a proof signed with someone else’s key', async () => {
+        // The whole point: only the server can mint one of these.
+        const forged = jwt.sign(
+            { opener_origin: 'https://console.puter.com', oidc_login: true },
+            'not-the-server-secret',
+            { keyid: 'v2' },
+        );
+        await expect(
+            callRoute(
+                'post',
+                '/auth/oidc/verify-popup-return',
+                makeReq({ body: { opener_state: forged } }),
+                makeRes().res,
+            ),
+        ).rejects.toMatchObject({ statusCode: 400 });
+    });
+
+    it('rejects an expired proof', async () => {
+        // Comfortably past `TokenService`'s 30s clock tolerance — the proof is
+        // redeemed on the very next request, so a stale one is never genuine.
+        const stale = server.services.token.sign(
+            'oidc-state',
+            { opener_origin: 'https://opener.test', oidc_login: true },
+            { expiresIn: -600 },
+        );
+        await expect(
+            callRoute(
+                'post',
+                '/auth/oidc/verify-popup-return',
+                makeReq({ body: { opener_state: stale } }),
+                makeRes().res,
+            ),
+        ).rejects.toMatchObject({ statusCode: 400 });
+    });
+
+    it('rejects a missing or non-string proof', async () => {
+        for (const bad of [undefined, null, '', 42, {}]) {
+            await expect(
+                callRoute(
+                    'post',
+                    '/auth/oidc/verify-popup-return',
+                    makeReq({ body: { opener_state: bad } }),
+                    makeRes().res,
+                ),
+            ).rejects.toMatchObject({ statusCode: 400 });
+        }
+    });
+
+    it('reports oidc_login false when the proof does not claim a login', async () => {
+        // The error leg mints one of these: a real return, but nothing was
+        // signed in on it, so it must not suppress the account picker.
+        const proof = server.services.oidc.signPopupReturn({
+            opener_origin: 'https://opener.test',
+            msg_id: '77',
+            oidc_login: false,
+        });
+        expect((await redeem(proof)).body).toMatchObject({ oidc_login: false });
+    });
+});

src/backend/controllers/oidc/OIDCController.ts

@@ -1,4 +1,4 @@
-/**
+/*
  * Copyright (C) 2024-present Puter Technologies Inc.
  *
  * This file is part of Puter.
@@ -47,6 +47,35 @@ const ALLOWED_ERRORS = [
     'signup_blocked',
 ] as const;
 
+/**
+ * Pick the display code for a failed user resolution.
+ *
+ * A `code` is only ever set when the signup-validate harness vetoed the signup,
+ * but the code it stamps comes from an abuse listener and is not drawn from
+ * {@link ALLOWED_ERRORS} — so clamping it directly turns every vetoed OIDC
+ * signup into a bare `unauthorized`, which reads as "sign-in broke" and hides
+ * both the real cause and the Request Code that support looks the decision up
+ * by. Anything unrecognized falls back to the veto's own category instead.
+ */
+function resolutionErrorCode(code: string | undefined): string {
+    if (!code) return 'unauthorized';
+    return (ALLOWED_ERRORS as readonly string[]).includes(code)
+        ? code
+        : 'signup_blocked';
+}
+
+// GUI pages an OIDC flow may return to: /desktop, /dashboard, and direct app
+// landings (/app/<name> and its desktop-booted twin /desktop/app/<name>,
+// mirroring APP_NAME_REGEX in AppDriver). Strict whitelist — never a
+// client-supplied URL (no open redirect).
+function isWhitelistedReturnPath(path: string): boolean {
+    return (
+        path === '/desktop' ||
+        path === '/dashboard' ||
+        /^(\/desktop)?\/app\/[a-zA-Z0-9_-]{1,100}$/.test(path)
+    );
+}
+
 function buildErrorRedirectUrl(
     origin: string,
     sourceFlow: string,
@@ -54,6 +83,11 @@ function buildErrorRedirectUrl(
     message: string,
     stateDecoded?: Record<string, unknown>,
     requestCode?: string,
+    // Signs the popup-return proof. Passed in because this is a module-level
+    // helper with no access to services; omitted by callers that have no
+    // state to attest (the proof is simply absent then, and the popup falls
+    // back to its browser-attested sources).
+    signPopupReturn?: (payload: Record<string, unknown>) => string,
 ): string {
     const targetFlow =
         OIDC_ERROR_REDIRECT_MAP[sourceFlow]?.[errorCondition] ?? sourceFlow;
@@ -62,6 +96,20 @@ function buildErrorRedirectUrl(
         ? message
         : 'unauthorized';
 
+    // Land back on the whitelisted page the flow started from (e.g. an
+    // /app/<name> landing) so the retry — and the eventual success — keeps
+    // the user's destination. redirect_uri comes from the signed state and
+    // was built server-side, but re-check the path against the whitelist.
+    let pagePath = '/';
+    if (typeof stateDecoded?.redirect_uri === 'string') {
+        try {
+            const statePath = new URL(stateDecoded.redirect_uri).pathname;
+            if (isWhitelistedReturnPath(statePath)) pagePath = statePath;
+        } catch {
+            // unparsable redirect_uri: fall back to the root page
+        }
+    }
+
     let params: URLSearchParams;
     if (stateDecoded?.embedded_in_popup && stateDecoded?.msg_id != null) {
         params = new URLSearchParams({
@@ -74,6 +122,19 @@ function buildErrorRedirectUrl(
         if (stateDecoded?.opener_origin) {
             params.set('opener_origin', String(stateDecoded.opener_origin));
         }
+        // Same reasoning as the success leg: the popup cannot tell a verified
+        // `opener_origin` from a typed one, so attest it. The error leg is a
+        // real return from the provider too — the flow failed, not the hop.
+        if (signPopupReturn) {
+            params.set(
+                'opener_state',
+                signPopupReturn({
+                    opener_origin: stateDecoded?.opener_origin ?? null,
+                    msg_id: stateDecoded?.msg_id ?? null,
+                    oidc_login: false,
+                }),
+            );
+        }
     } else {
         params = new URLSearchParams({
             action: targetFlow,
@@ -84,7 +145,7 @@ function buildErrorRedirectUrl(
     if (requestCode) {
         params.set('request_code', requestCode);
     }
-    return `${base}/?${params.toString()}`;
+    return `${base}${pagePath}?${params.toString()}`;
 }
 
 function appendQueryParam(url: string, key: string, value: string): string {
@@ -101,8 +162,8 @@ function constantTimeEqual(a: string, b: string): boolean {
 }
 
 /**
- * True iff `target` parses as a URL whose origin equals `origin`. Used to
- * clamp OIDC redirect targets — `startsWith` would accept
+ * True iff `target` parses as a URL whose origin equals `origin`. Used to clamp
+ * OIDC redirect targets — `startsWith` would accept
  * `https://puter.com.evil.com` against `https://puter.com`.
  */
 function isSameOrigin(target: string, origin: string): boolean {
@@ -120,6 +181,51 @@ function isSameOrigin(target: string, origin: string): boolean {
  */
 export class OIDCController extends PuterController {
     registerRoutes(router: PuterRouter): void {
+        // -- POST /auth/oidc/verify-popup-return ---------------------
+        // Public — hand back the facts a popup-return proof attests to.
+        //
+        // A sign-in popup returning from a provider is told the opener's
+        // origin and that a login completed. It cannot check either: the
+        // values arrive as query parameters, and a URL built from a verified
+        // `state` looks exactly like one an attacker typed. The opener's
+        // origin decides which app a token gets minted for, so the popup
+        // redeems the signed proof here instead of believing the raw
+        // parameters.
+        //
+        // Unauthenticated on purpose — it reveals nothing the caller did not
+        // already hand over, and a forged or expired proof yields nothing.
+
+        router.post(
+            '/auth/oidc/verify-popup-return',
+            {
+                subdomain: 'api',
+                rateLimit: {
+                    scope: 'oidc-verify-popup-return',
+                    limit: 60,
+                    window: 60_000,
+                },
+            },
+            async (req: Request, res: Response) => {
+                const proof = req.body?.opener_state;
+                if (typeof proof !== 'string' || !proof) {
+                    throw new HttpError(400, 'Missing `opener_state`', {
+                        legacyCode: 'bad_request',
+                    });
+                }
+                const decoded = this.services.oidc.verifyPopupReturn(proof);
+                if (!decoded) {
+                    throw new HttpError(400, 'Invalid `opener_state`', {
+                        legacyCode: 'bad_request',
+                    });
+                }
+                res.json({
+                    opener_origin: decoded.opener_origin ?? null,
+                    msg_id: decoded.msg_id ?? null,
+                    oidc_login: decoded.oidc_login === true,
+                });
+            },
+        );
+
         // -- GET /auth/oidc/providers --------------------------------
         // Public — list enabled provider IDs for the frontend.
 
@@ -166,15 +272,15 @@ export class OIDCController extends PuterController {
 
                 let appRedirectUri = flowRedirects[flow] ?? (origin || '/');
 
-                // Optional GUI return path so login started from /desktop or
-                // /dashboard lands back there. Strict whitelist — never a
-                // client-supplied URL (no open redirect).
+                // Optional GUI return path so login started from /desktop,
+                // /dashboard, or an /app/<name> landing lands back there.
                 const rawReturnTo = Array.isArray(req.query.return_to)
                     ? req.query.return_to[0]
                     : req.query.return_to;
                 if (
                     (flow === 'login' || flow === 'signup') &&
-                    (rawReturnTo === '/desktop' || rawReturnTo === '/dashboard')
+                    typeof rawReturnTo === 'string' &&
+                    isWhitelistedReturnPath(rawReturnTo)
                 ) {
                     appRedirectUri = `${origin}${rawReturnTo}`;
                 }
@@ -315,9 +421,10 @@ export class OIDCController extends PuterController {
                         origin,
                         'login',
                         'other',
-                        resolved.code ?? 'unauthorized',
+                        resolutionErrorCode(resolved.code),
                         stateDecoded,
                         resolved.requestCode,
+                        (p) => this.services.oidc.signPopupReturn(p),
                     ),
                 );
             }
@@ -335,6 +442,8 @@ export class OIDCController extends PuterController {
                         'other',
                         'account_suspended',
                         stateDecoded,
+                        undefined,
+                        (p) => this.services.oidc.signPopupReturn(p),
                     ),
                 );
             }
@@ -350,6 +459,7 @@ export class OIDCController extends PuterController {
             const origin = this.config.origin ?? '';
             const result = await this.#processCallback(req, res, 'signup');
             if ('error' in result) {
+                console.warn(`OIDC signup callback error: ${result.error}`);
                 return res.redirect(
                     302,
                     buildErrorRedirectUrl(
@@ -378,9 +488,10 @@ export class OIDCController extends PuterController {
                         origin,
                         'signup',
                         'other',
-                        resolved.code ?? 'unauthorized',
+                        resolutionErrorCode(resolved.code),
                         stateDecoded,
                         resolved.requestCode,
+                        (p) => this.services.oidc.signPopupReturn(p),
                     ),
                 );
             }
@@ -395,6 +506,8 @@ export class OIDCController extends PuterController {
                         'other',
                         'account_suspended',
                         stateDecoded,
+                        undefined,
+                        (p) => this.services.oidc.signPopupReturn(p),
                     ),
                 );
             }
@@ -497,13 +610,14 @@ if (window.opener) {
 
     /**
      * Resolve an OIDC callback to a Puter user. In order:
-     *   1. Existing link on (provider, sub) → that user.
-     *   2. Email matches an existing account whose email is CONFIRMED →
-     *      link (provider, sub) to that user.
-     *   3. Email matches an account whose email is UNCONFIRMED → refuse.
-     *      We don't know who owns an unconfirmed address, so linking would
-     *      let whoever controls the OIDC identity hijack a pending signup.
-     *   4. Otherwise create a new user and link.
+     *
+     * 1. Existing link on (provider, sub) → that user.
+     * 2. Email matches an existing account whose email is CONFIRMED → link
+     *    (provider, sub) to that user.
+     * 3. Email matches an account whose email is UNCONFIRMED → refuse. We don't
+     *    know who owns an unconfirmed address, so linking would let whoever
+     *    controls the OIDC identity hijack a pending signup.
+     * 4. Otherwise create a new user and link.
      *
      * Step 2 also requires `email_verified !== false` on the OIDC side,
      * otherwise a malicious IdP could claim someone else's email.
@@ -673,6 +787,22 @@ if (window.opener) {
 
         if (stateDecoded.embedded_in_popup) {
             target = appendQueryParam(target, 'oidc_login', 'true');
+            // `opener_origin` and `oidc_login` reach the popup as bare query
+            // parameters, which say nothing about where they came from: the
+            // URL a verified state produces is byte-identical to one anybody
+            // can type. The popup treats the opener's origin as the app
+            // identity to mint a token for, so it needs the integrity this
+            // state already carries — re-signed here, at the one point where
+            // the round trip is known to have actually happened.
+            target = appendQueryParam(
+                target,
+                'opener_state',
+                this.services.oidc.signPopupReturn({
+                    opener_origin: stateDecoded.opener_origin ?? null,
+                    msg_id: stateDecoded.msg_id ?? null,
+                    oidc_login: true,
+                }),
+            );
         }
 
         if (extraQueryParams) {