diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..a8fa1c3
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,33 @@
+name: ci
+
+# Runs the test suite on every pull request, and on main after a merge.
+on:
+  pull_request:
+  push:
+    branches: [main]
+
+permissions: {}
+
+concurrency:
+  group: ci-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  test:
+    name: Test (node ${{ matrix.node }})
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+    strategy:
+      fail-fast: false
+      matrix:
+        node: [18, 20, 22]
+
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: ${{ matrix.node }}
+          cache: npm
+      - run: npm ci
+      - run: npm test
diff --git a/.github/workflows/pr-notify.yml b/.github/workflows/pr-notify.yml
new file mode 100644
index 0000000..b92d255
--- /dev/null
+++ b/.github/workflows/pr-notify.yml
@@ -0,0 +1,32 @@
+name: pr-notify
+
+# Posts to Slack when a PR lands on main. Opening a PR notifies nobody —
+# this channel reports what actually merged.
+on:
+  pull_request:
+    branches: [main]
+    types: [closed]
+
+permissions: {}
+
+jobs:
+  notify:
+    name: Notify Slack
+    runs-on: ubuntu-latest
+    if: ${{ github.event.pull_request.merged }}
+
+    env:
+      SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
+      PR_TITLE: ${{ github.event.pull_request.title }}
+      PR_URL: ${{ github.event.pull_request.html_url }}
+      PR_NUMBER: ${{ github.event.pull_request.number }}
+      PR_AUTHOR: ${{ github.event.pull_request.user.login }}
+
+    steps:
+      - name: Notify Slack (merged to main)
+        if: ${{ env.SLACK_WEBHOOK_URL != '' }}
+        run: |
+          TEXT=$(jq -n \
+            --arg t "$PR_TITLE" --arg u "$PR_URL" --arg n "$PR_NUMBER" --arg a "$PR_AUTHOR" \
+            '{text: ("*plain-forge*: <" + $u + "|#" + $n + " " + $t + "> merged to `main` :white_check_mark: — by *" + $a + "*.")}')
+          curl -s -X POST "$SLACK_WEBHOOK_URL" -H 'Content-type: application/json' --data "$TEXT"
diff --git a/.github/workflows/publish.yml b/.github/workflows/publish.yml
new file mode 100644
index 0000000..4922b9a
--- /dev/null
+++ b/.github/workflows/publish.yml
@@ -0,0 +1,126 @@
+name: publish
+
+# Manual release. Bump the version in package.json first, merge it, then run
+# this workflow from the Actions tab against main.
+#
+# Auth is OIDC (npm trusted publishing) — no NPM_TOKEN secret. The trusted
+# publisher must be configured once on npmjs.com for this repo and this exact
+# workflow filename (publish.yml).
+on:
+  workflow_dispatch:
+
+# Least privilege by default: jobs get no GITHUB_TOKEN scopes unless they
+# opt in below.
+permissions: {}
+
+concurrency:
+  group: publish
+  cancel-in-progress: false
+
+jobs:
+  test:
+    name: Test
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+
+    env:
+      SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
+
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 20
+          cache: npm
+      - run: npm ci
+      - run: npm test
+
+      - name: Notify Slack (tests failed)
+        if: ${{ failure() && env.SLACK_WEBHOOK_URL != '' }}
+        run: |
+          curl -s -X POST "$SLACK_WEBHOOK_URL" \
+            -H 'Content-type: application/json' \
+            --data "{\"text\":\"*plain-forge*: release halted — tests FAILED :x:. Nothing was published to npm. See <${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}|the run log>.\"}"
+
+  publish:
+    name: Publish to npm
+    needs: test
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write      # push the version tag, create the release
+      id-token: write      # OIDC token for trusted publishing
+
+    env:
+      SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
+
+    steps:
+      - name: Refuse to publish from anywhere but main
+        if: github.ref != 'refs/heads/main'
+        run: |
+          echo "::error::releases are cut from main, not ${{ github.ref_name }}"
+          exit 1
+
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 22      # trusted publishing needs >= 22.14
+          cache: npm
+
+      - name: Use an npm that supports trusted publishing
+        run: |
+          npm install -g npm@latest
+          npm --version
+
+      - run: npm ci
+
+      - name: Read version
+        id: pkg
+        run: echo "version=$(node -p "require('./package.json').version")" >> "$GITHUB_OUTPUT"
+
+      - name: Refuse if this version is already on npm
+        run: |
+          if npm view "plain-forge@${{ steps.pkg.outputs.version }}" version >/dev/null 2>&1; then
+            echo "::error::plain-forge@${{ steps.pkg.outputs.version }} is already published — bump the version in package.json first"
+            exit 1
+          fi
+
+      - name: Notify Slack (start)
+        if: ${{ env.SLACK_WEBHOOK_URL != '' }}
+        run: |
+          curl -s -X POST "$SLACK_WEBHOOK_URL" \
+            -H 'Content-type: application/json' \
+            --data "{\"text\":\"*plain-forge*: release of \`v${{ steps.pkg.outputs.version }}\` started by *${{ github.actor }}* — publishing to npm...\"}"
+
+      # No NODE_AUTH_TOKEN: npm exchanges the GitHub OIDC token for a
+      # short-lived npm token. Provenance is attached automatically.
+      - name: Publish
+        run: npm publish --access public
+
+      - name: Tag the release
+        env:
+          VERSION: ${{ steps.pkg.outputs.version }}
+        run: |
+          git tag "v$VERSION"
+          git push origin "v$VERSION"
+
+      - name: Create the GitHub release
+        env:
+          GH_TOKEN: ${{ github.token }}
+          VERSION: ${{ steps.pkg.outputs.version }}
+        run: gh release create "v$VERSION" --title "v$VERSION" --generate-notes
+
+      - name: Notify Slack (success)
+        if: ${{ success() && env.SLACK_WEBHOOK_URL != '' }}
+        run: |
+          curl -s -X POST "$SLACK_WEBHOOK_URL" \
+            -H 'Content-type: application/json' \
+            --data "{\"text\":\"*plain-forge*: \`v${{ steps.pkg.outputs.version }}\` published to npm :white_check_mark:. Install with \`npx plain-forge@latest update\`.\"}"
+
+      - name: Notify Slack (failure)
+        if: ${{ failure() && env.SLACK_WEBHOOK_URL != '' }}
+        run: |
+          curl -s -X POST "$SLACK_WEBHOOK_URL" \
+            -H 'Content-type: application/json' \
+            --data "{\"text\":\"*plain-forge*: publishing \`v${{ steps.pkg.outputs.version }}\` to npm FAILED :x:. See <${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}|the run log>.\"}"
diff --git a/CLAUDE.md b/CLAUDE.md
index 833e56d..501fe0b 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -16,8 +16,8 @@ So a change here is almost always one of: (a) editing the installer CLI, or (b)
 ## Commands
 
 ```bash
-npm test                                                   # full suite: node --test "test/**/*.test.mjs"
-node --test --test-name-pattern="<regex>" "test/**/*.test.mjs"   # run a single test by name
+npm test                                                   # full suite: node --test test/*.test.mjs
+node --test --test-name-pattern="<regex>" test/*.test.mjs  # run a single test by name
 node --test test/cli.test.mjs                              # run a single test file
 ```
 
diff --git a/package.json b/package.json
index 5afa7c9..e095b07 100644
--- a/package.json
+++ b/package.json
@@ -33,7 +33,7 @@
   "scripts": {
     "build": "tsx bin/forge-build.ts",
     "clean": "tsx bin/forge-build.ts --clean",
-    "test": "node --test \"test/**/*.test.mjs\""
+    "test": "node --test test/*.test.mjs"
   },
   "devDependencies": {
     "@types/node": "^22.10.0",