diff --git a/.github/workflows/publish.yml b/.github/workflows/publish.yml
new file mode 100644
index 0000000..8378096
--- /dev/null
+++ b/.github/workflows/publish.yml
@@ -0,0 +1,41 @@
+name: publish
+
+on:
+  push:
+    tags:
+      - "v*"
+
+permissions:
+  contents: read
+  id-token: write
+
+jobs:
+  publish:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: 22
+          registry-url: https://registry.npmjs.org
+
+      - name: Setup Bun
+        uses: oven-sh/setup-bun@v2
+
+      - name: Install dependencies
+        run: bun install --frozen-lockfile
+
+      - name: Typecheck
+        run: bun run check
+
+      - name: Test
+        run: bun test
+
+      - name: Build
+        run: bun run build
+
+      - name: Publish to npm
+        run: npm publish --provenance --access public
diff --git a/.npmignore b/.npmignore
new file mode 100644
index 0000000..7854fde
--- /dev/null
+++ b/.npmignore
@@ -0,0 +1,14 @@
+# Defense-in-depth: `files` in package.json is the primary allowlist.
+# This file excludes junk from the published tarball even if the
+# allowlist is ever loosened.
+test/
+docs/reports/
+docs/evidence/
+scripts/accept/
+worktrees/
+.github/
+*.log
+bun.lock
+coverage/
+.nyc_output/
+*.tsbuildinfo
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..5e3e058
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2026 Heretek-AI
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/package.json b/package.json
index 6fa7f2a..29c243e 100644
--- a/package.json
+++ b/package.json
@@ -2,14 +2,57 @@
   "name": "@heretek-ai/opencode-harness",
   "version": "1.0.0",
   "description": "Lean OpenCode v2 in-process harness plugin: Hashline edits, AST codemods, KV-cache-safe context budgeting, permission guards, and DOM geometry auditing.",
-  "type": "module",
-  "main": "./src/index.ts",
-  "exports": {
-    ".": "./src/index.ts"
+  "license": "MIT",
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/Heretek-AI/opencode-harness.git"
   },
+  "homepage": "https://github.com/Heretek-AI/opencode-harness",
+  "bugs": {
+    "url": "https://github.com/Heretek-AI/opencode-harness/issues"
+  },
+  "author": "Heretek-AI",
+  "keywords": [
+    "opencode",
+    "opencode-plugin",
+    "hashline",
+    "ast-codemod",
+    "permission-guard",
+    "circuit-breaker",
+    "context-budget",
+    "dom-audit"
+  ],
+  "engines": {
+    "bun": ">=1.0.0",
+    "node": ">=22.0.0"
+  },
+  "sideEffects": false,
+  "publishConfig": {
+    "access": "public",
+    "provenance": true
+  },
+  "type": "module",
+  "main": "./dist/index.js",
+  "types": "./dist/index.d.ts",
+  "exports": {
+    ".": {
+      "types": "./dist/index.d.ts",
+      "import": "./dist/index.js",
+      "default": "./dist/index.js"
+    }
+  },
+  "files": [
+    "dist",
+    "src",
+    "README.md",
+    "LICENSE",
+    "AGENTS.md"
+  ],
   "scripts": {
     "check": "tsc --noEmit",
     "test": "bun test",
+    "build": "tsc -p tsconfig.build.json",
+    "prepublishOnly": "bun run check && bun test && npm run build",
     "accept": "bash scripts/accept/run.sh"
   },
   "dependencies": {
diff --git a/src/editors/ast-codemod.ts b/src/editors/ast-codemod.ts
index 25ea711..ad0b95f 100644
--- a/src/editors/ast-codemod.ts
+++ b/src/editors/ast-codemod.ts
@@ -14,7 +14,7 @@
  */
 
 import { createRequire } from "node:module";
-import { resolveSafePath } from "./hashline-tools";
+import { resolveSafePath } from "./hashline-tools.js";
 
 export type AstLanguage =
   | "typescript"
diff --git a/src/guards/permission-guard.ts b/src/guards/permission-guard.ts
index eb672e5..d018da1 100644
--- a/src/guards/permission-guard.ts
+++ b/src/guards/permission-guard.ts
@@ -25,7 +25,7 @@
 import {
   classifyShellCommand,
   isDestructiveShellCommand,
-} from "./shell-parse";
+} from "./shell-parse.js";
 
 export const DEFAULT_LOCKED_CONTRACT_GLOBS: string[] = [
   "**/contracts/**",
diff --git a/src/index.ts b/src/index.ts
index 6235286..9de60c6 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -32,50 +32,50 @@ import {
   astRewriteFile,
   astSearch,
   type AstLanguage,
-} from "./editors/ast-codemod";
+} from "./editors/ast-codemod.js";
 import {
   hashEditFile,
   hashReadFile,
   type HashEditHunk,
-} from "./editors/hashline-tools";
+} from "./editors/hashline-tools.js";
 import {
   defaultGuardConfig,
   evaluateBoardGuard,
   type GuardPolicyConfig,
   type GuardRequest,
   type GuardVerdict,
-} from "./guards/permission-guard";
+} from "./guards/permission-guard.js";
 import {
   commandPrefixOf,
   recordToolAttempt,
   type CircuitBreakerVerdict,
-} from "./guards/circuit-breaker";
+} from "./guards/circuit-breaker.js";
 import {
   buildDynamicContextBlocks,
   injectContextBudgetIntoMessages,
   packBlocks,
   type LessonInput,
   type SessionEvent,
-} from "./context/context-budget";
+} from "./context/context-budget.js";
 import {
   auditLivePageWithPlaywright,
   evaluateDomGeometryInPage,
   type DomElementInput,
   type ViewportInput,
-} from "./ui-auditor/dom-auditor";
+} from "./ui-auditor/dom-auditor.js";
 
-export * from "./editors/hashline-tools";
-export * from "./editors/ast-codemod";
-export * from "./guards/shell-parse";
-export * from "./guards/permission-guard";
-export * from "./guards/circuit-breaker";
-export * from "./context/context-budget";
-export * from "./ui-auditor/dom-auditor";
-export { getRecommendedMcpConfig } from "./ui-auditor/mcp-defaults";
+export * from "./editors/hashline-tools.js";
+export * from "./editors/ast-codemod.js";
+export * from "./guards/shell-parse.js";
+export * from "./guards/permission-guard.js";
+export * from "./guards/circuit-breaker.js";
+export * from "./context/context-budget.js";
+export * from "./ui-auditor/dom-auditor.js";
+export { getRecommendedMcpConfig } from "./ui-auditor/mcp-defaults.js";
 export type {
   McpServerEntry,
   RecommendedMcpConfig,
-} from "./ui-auditor/mcp-defaults";
+} from "./ui-auditor/mcp-defaults.js";
 
 export const HARNESS_NAME = "@heretek-ai/opencode-harness";
 export const HARNESS_VERSION = "1.0.0";
diff --git a/tsconfig.build.json b/tsconfig.build.json
new file mode 100644
index 0000000..ada614b
--- /dev/null
+++ b/tsconfig.build.json
@@ -0,0 +1,15 @@
+{
+  "extends": "./tsconfig.json",
+  "compilerOptions": {
+    "outDir": "dist",
+    "rootDir": "src",
+    "declaration": true,
+    "declarationMap": true,
+    "sourceMap": true,
+    "noEmit": false,
+    "module": "ESNext",
+    "moduleResolution": "bundler"
+  },
+  "include": ["src/**/*"],
+  "exclude": ["test", "scripts", "docs"]
+}