diff --git a/.github/scripts/release-policy.cjs b/.github/scripts/release-policy.cjs
new file mode 100644
index 0000000..e8ebc35
--- /dev/null
+++ b/.github/scripts/release-policy.cjs
@@ -0,0 +1,135 @@
+const {execFileSync} = require('node:child_process')
+const fs = require('node:fs')
+
+const RUNTIME_MANIFEST_KEYS = new Set([
+  'dependencies',
+  'optionalDependencies',
+  'overrides',
+  'peerDependencies'
+])
+
+function equal(left, right) {
+  return JSON.stringify(left) === JSON.stringify(right)
+}
+
+function withoutRuntimeDependencies(manifest) {
+  return Object.fromEntries(
+    Object.entries(manifest).filter(([key]) => !RUNTIME_MANIFEST_KEYS.has(key))
+  )
+}
+
+function runtimeDependenciesChanged(baseManifest, headManifest) {
+  return [...RUNTIME_MANIFEST_KEYS].some(
+    key => !equal(baseManifest[key], headManifest[key])
+  )
+}
+
+function isAccompanyingFile(path) {
+  return (
+    path.startsWith('.github/') ||
+    path.startsWith('__tests__/') ||
+    path.startsWith('test/') ||
+    path.startsWith('tests/') ||
+    path.startsWith('docs/') ||
+    path.endsWith('.md')
+  )
+}
+
+function classifyRelease(changedFiles, baseManifest, headManifest) {
+  const files = [...new Set(changedFiles)]
+  const hasSource = files.some(path => path.startsWith('src/'))
+  const hasDist = files.some(path => path.startsWith('dist/'))
+  const hasAction = files.includes('action.yml')
+  const hasPackage = files.includes('package.json')
+  const hasLock = files.includes('package-lock.json')
+  const hasShippedChange = hasSource || hasDist || hasAction
+
+  if (!hasShippedChange) {
+    return {kind: 'none', reason: 'No shipped files changed'}
+  }
+
+  if (hasSource && !hasDist) {
+    return {
+      kind: 'stale-bundle',
+      reason: 'src/** changed without a rebuilt dist/** bundle'
+    }
+  }
+
+  const knownFiles = files.every(
+    path =>
+      path.startsWith('src/') ||
+      path.startsWith('dist/') ||
+      path === 'action.yml' ||
+      path === 'package.json' ||
+      path === 'package-lock.json' ||
+      isAccompanyingFile(path)
+  )
+  const dependencyOnlyManifest =
+    hasPackage &&
+    hasLock &&
+    runtimeDependenciesChanged(baseManifest, headManifest) &&
+    equal(
+      withoutRuntimeDependencies(baseManifest),
+      withoutRuntimeDependencies(headManifest)
+    )
+
+  if (
+    hasDist &&
+    !hasSource &&
+    !hasAction &&
+    knownFiles &&
+    dependencyOnlyManifest
+  ) {
+    return {
+      kind: 'patch',
+      reason: 'Only bundled runtime dependencies changed'
+    }
+  }
+
+  return {
+    kind: 'minor',
+    reason: knownFiles
+      ? 'Potentially behavioral shipped files changed'
+      : 'Unknown files accompany shipped changes'
+  }
+}
+
+function readManifest(ref) {
+  return JSON.parse(
+    execFileSync('git', ['show', `${ref}:package.json`], {encoding: 'utf8'})
+  )
+}
+
+function changedFiles(base, head) {
+  return execFileSync('git', ['diff', '--name-only', '-z', base, head])
+    .toString()
+    .split('\0')
+    .filter(Boolean)
+}
+
+function writeOutput(result) {
+  const output = process.env.GITHUB_OUTPUT
+  if (!output) return
+
+  fs.appendFileSync(
+    output,
+    `classification=${result.kind}\nreason=${result.reason}\n`
+  )
+}
+
+if (require.main === module) {
+  const [base, head = 'HEAD'] = process.argv.slice(2)
+  if (!base) {
+    throw new Error('Usage: release-policy.cjs <base-ref> [head-ref]')
+  }
+
+  const result = classifyRelease(
+    changedFiles(base, head),
+    readManifest(base),
+    readManifest(head)
+  )
+  writeOutput(result)
+  console.log(`${result.kind}: ${result.reason}`)
+}
+
+module.exports = {classifyRelease}
diff --git a/.github/workflows/automatic-release.yml b/.github/workflows/automatic-release.yml
new file mode 100644
index 0000000..8f5e03b
--- /dev/null
+++ b/.github/workflows/automatic-release.yml
@@ -0,0 +1,85 @@
+name: Automatic release
+
+on:
+  schedule:
+    - cron: '17 13 * * *'
+  workflow_dispatch:
+
+# Releases made with GITHUB_TOKEN do not recursively trigger push/release workflows.
+# The daily schedule invokes the reusable release workflow directly.
+permissions:
+  copilot-requests: write
+  contents: write
+  pull-requests: read
+
+jobs:
+  classify:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+    outputs:
+      base-ref: ${{ steps.release.outputs.base-ref }}
+      bump: ${{ steps.release.outputs.bump }}
+      draft: ${{ steps.release.outputs.draft }}
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Classify changes
+        id: policy
+        run: |
+          set -euo pipefail
+          LATEST=$(
+            git tag --list |
+              awk '/^v(0|[1-9][0-9]*)\.(0|[1-9][0-9]*)\.(0|[1-9][0-9]*)$/' |
+              sort -V |
+              tail -n 1
+          )
+          if [ -z "$LATEST" ]; then
+            echo "::error::Automatic releases require an existing stable semver tag"
+            exit 1
+          fi
+          echo "base-ref=$LATEST" >> "$GITHUB_OUTPUT"
+          node .github/scripts/release-policy.cjs "$LATEST" "$GITHUB_SHA"
+
+      - name: Select release behavior
+        id: release
+        env:
+          BASE_REF: ${{ steps.policy.outputs.base-ref }}
+          CLASSIFICATION: ${{ steps.policy.outputs.classification }}
+          REASON: ${{ steps.policy.outputs.reason }}
+        run: |
+          set -euo pipefail
+          echo "$CLASSIFICATION: $REASON"
+          echo "base-ref=$BASE_REF" >> "$GITHUB_OUTPUT"
+          case "$CLASSIFICATION" in
+            none)
+              ;;
+            patch)
+              echo "bump=patch" >> "$GITHUB_OUTPUT"
+              echo "draft=false" >> "$GITHUB_OUTPUT"
+              ;;
+            minor)
+              echo "bump=minor" >> "$GITHUB_OUTPUT"
+              echo "draft=true" >> "$GITHUB_OUTPUT"
+              ;;
+            stale-bundle)
+              echo "::error::$REASON"
+              exit 1
+              ;;
+            *)
+              echo "::error::Unexpected release classification: $CLASSIFICATION"
+              exit 1
+              ;;
+          esac
+
+  release:
+    needs: classify
+    if: needs.classify.result == 'success' && needs.classify.outputs.bump != ''
+    uses: ./.github/workflows/release.yml
+    with:
+      automatic: true
+      base-ref: ${{ needs.classify.outputs.base-ref }}
+      bump: ${{ needs.classify.outputs.bump }}
+      draft: ${{ fromJSON(needs.classify.outputs.draft) }}
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 5572fbe..b46264a 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -1,6 +1,21 @@
 name: Release
 
 on:
+  workflow_call:
+    inputs:
+      automatic:
+        required: false
+        default: false
+        type: boolean
+      base-ref:
+        required: false
+        type: string
+      bump:
+        required: true
+        type: string
+      draft:
+        required: true
+        type: boolean
   workflow_dispatch:
     inputs:
       bump:
@@ -8,16 +23,17 @@ on:
         required: true
         default: 'patch'
         type: choice
-        options:
-          - patch
-          - minor
-          - major
+        options: [patch, minor, major]
       draft:
         description: 'Create the release as a draft'
         required: true
         default: false
         type: boolean
 
+concurrency:
+  group: release-${{ github.repository }}
+  cancel-in-progress: false
+
 jobs:
   release:
     runs-on: ubuntu-latest
@@ -25,7 +41,6 @@ jobs:
       copilot-requests: write
       contents: write
       pull-requests: read
-
     steps:
       - uses: actions/checkout@v4
         with:
@@ -33,24 +48,30 @@ jobs:
 
       - name: Determine versions
         id: version
+        env:
+          BUMP: ${{ inputs.bump }}
+          EXPECTED_BASE: ${{ inputs.base-ref }}
         run: |
-          LATEST=$(git tag --list 'v*.*.*' --sort=-v:refname | head -n 1)
-          if [ -z "$LATEST" ]; then
-            LATEST="v0.0.0"
+          set -euo pipefail
+          LATEST=$(git tag --list | awk '/^v(0|[1-9][0-9]*)\.(0|[1-9][0-9]*)\.(0|[1-9][0-9]*)$/' | sort -V | tail -1)
+          LATEST=${LATEST:-v0.0.0}
+          if [ -n "$EXPECTED_BASE" ] && [ "$LATEST" != "$EXPECTED_BASE" ]; then
+            echo "::error::Latest stable release advanced to $LATEST; retry automation"
+            exit 1
           fi
-          echo "previous=$LATEST" >> "$GITHUB_OUTPUT"
-
-          # Strip 'v' prefix, split, bump, reassemble
-          IFS='.' read -r MAJOR MINOR PATCH <<< "${LATEST#v}"
-          case "${{ inputs.bump }}" in
+          case "$BUMP" in
+            major|minor|patch) ;;
+            *) echo "::error::Invalid version bump: $BUMP"; exit 1 ;;
+          esac
+          IFS=. read -r MAJOR MINOR PATCH <<< "${LATEST#v}"
+          case "$BUMP" in
             major) MAJOR=$((MAJOR + 1)); MINOR=0; PATCH=0 ;;
             minor) MINOR=$((MINOR + 1)); PATCH=0 ;;
             patch) PATCH=$((PATCH + 1)) ;;
           esac
-          NEXT="v${MAJOR}.${MINOR}.${PATCH}"
-          echo "next=$NEXT" >> "$GITHUB_OUTPUT"
-          echo "major=v${MAJOR}" >> "$GITHUB_OUTPUT"
-          echo "Releasing $NEXT (previous: $LATEST)"
+          echo "previous=$LATEST" >> "$GITHUB_OUTPUT"
+          echo "next=v$MAJOR.$MINOR.$PATCH" >> "$GITHUB_OUTPUT"
+          echo "major=v$MAJOR" >> "$GITHUB_OUTPUT"
 
       - name: Generate release notes
         id: notes
@@ -61,16 +82,53 @@ jobs:
         env:
           GITHUB_TOKEN: ${{ github.token }}
 
-      - name: Create GitHub Release
-        uses: softprops/action-gh-release@v2
-        with:
-          tag_name: ${{ steps.version.outputs.next }}
-          name: ${{ steps.version.outputs.next }}
-          body: ${{ steps.notes.outputs.release-notes }}
-          draft: ${{ inputs.draft }}
-          target_commitish: ${{ github.sha }}
-
-      - name: Update major version tag
+      - name: Create or update release
+        env:
+          AUTOMATIC: ${{ inputs.automatic || false }}
+          DRAFT: ${{ inputs.draft }}
+          GH_TOKEN: ${{ github.token }}
+          MAJOR: ${{ steps.version.outputs.major }}
+          NEXT: ${{ steps.version.outputs.next }}
+          NOTES: ${{ steps.notes.outputs.release-notes }}
         run: |
-          git tag -f "${{ steps.version.outputs.major }}" "${{ github.sha }}"
-          git push origin "refs/tags/${{ steps.version.outputs.major }}" --force
+          set -euo pipefail
+          NOTES_FILE="$RUNNER_TEMP/release-notes.md"
+          printf '%s\n' "$NOTES" > "$NOTES_FILE"
+          gh release list --limit 100 --json tagName,isDraft,isPrerelease > "$RUNNER_TEMP/releases.json"
+          MATCH_DRAFT=$(jq -r --arg tag "$NEXT" '.[] | select(.tagName == $tag) | .isDraft' "$RUNNER_TEMP/releases.json")
+
+          if [ "$DRAFT" = "true" ]; then
+            OTHER_DRAFTS=$(jq -r --arg tag "$NEXT" \
+              '.[] | select(.isDraft and .tagName != $tag and (.tagName | test("^v(0|[1-9][0-9]*)\\.(0|[1-9][0-9]*)\\.(0|[1-9][0-9]*)$"))) | .tagName' \
+              "$RUNNER_TEMP/releases.json")
+            if [ -n "$OTHER_DRAFTS" ]; then
+              echo "::error::Resolve conflicting draft release(s): ${OTHER_DRAFTS//$'\n'/, }"
+              exit 1
+            fi
+          elif [ "$AUTOMATIC" = "true" ] && [ "$MATCH_DRAFT" = "true" ]; then
+            echo "::error::Automatic patch release refuses to publish existing draft $NEXT"
+            exit 1
+          fi
+
+          if [ "$MATCH_DRAFT" = "true" ]; then
+            gh release edit "$NEXT" --title "$NEXT" --notes-file "$NOTES_FILE" \
+              --target "$GITHUB_SHA" --draft="$DRAFT"
+          elif [ -z "$MATCH_DRAFT" ]; then
+            DRAFT_FLAG=()
+            [ "$DRAFT" = "true" ] && DRAFT_FLAG=(--draft)
+            gh release create "$NEXT" --title "$NEXT" --notes-file "$NOTES_FILE" \
+              --target "$GITHUB_SHA" "${DRAFT_FLAG[@]}"
+          else
+            echo "$NEXT is already published; reconciling its major tag"
+          fi
+
+          if [ "$DRAFT" != "true" ]; then
+            git fetch --force --tags origin
+            HIGHEST=$(gh release list --limit 100 --exclude-drafts --exclude-pre-releases \
+              --json tagName --jq '.[].tagName' |
+              awk -v major="${MAJOR#v}" '$0 ~ ("^v" major "\\.(0|[1-9][0-9]*)\\.(0|[1-9][0-9]*)$")' |
+              sort -V | tail -1)
+            [ -n "$HIGHEST" ] || { echo "::error::No stable release found for $MAJOR"; exit 1; }
+            git tag -f "$MAJOR" "${HIGHEST}^{commit}"
+            git push origin "refs/tags/$MAJOR" --force
+          fi
diff --git a/__tests__/release-policy.test.ts b/__tests__/release-policy.test.ts
new file mode 100644
index 0000000..534c9bf
--- /dev/null
+++ b/__tests__/release-policy.test.ts
@@ -0,0 +1,71 @@
+const {classifyRelease} = require('../.github/scripts/release-policy.cjs')
+
+const baseManifest = {
+  name: 'action',
+  version: '1.0.0',
+  dependencies: {runtime: '1.0.0'},
+  devDependencies: {test: '1.0.0'}
+}
+
+function classify(
+  files: string[],
+  headManifest: Record<string, unknown> = baseManifest
+) {
+  return classifyRelease(files, baseManifest, headManifest)
+}
+
+describe('release policy', () => {
+  it('does nothing when only accompanying files change', () => {
+    expect(
+      classify(['README.md', '__tests__/release-policy.test.ts', '.github/a.yml'])
+    ).toEqual({kind: 'none', reason: 'No shipped files changed'})
+  })
+
+  it('publishes a patch for dependency-only bundle updates', () => {
+    expect(
+      classify(['package.json', 'package-lock.json', 'dist/index.js'], {
+        ...baseManifest,
+        dependencies: {runtime: '1.1.0'}
+      })
+    ).toEqual({
+      kind: 'patch',
+      reason: 'Only bundled runtime dependencies changed'
+    })
+  })
+
+  it('allows tests, docs, and workflows alongside a dependency patch', () => {
+    expect(
+      classify(
+        [
+          'package.json',
+          'package-lock.json',
+          'dist/index.js',
+          '__tests__/runtime.test.ts',
+          'docs/dependencies.md',
+          '.github/dependabot.yml'
+        ],
+        {...baseManifest, dependencies: {runtime: '1.1.0'}}
+      ).kind
+    ).toBe('patch')
+  })
+
+  it.each([
+    [['src/index.ts', 'dist/index.js'], baseManifest],
+    [['action.yml'], baseManifest],
+    [['dist/index.js'], baseManifest],
+    [
+      ['package.json', 'package-lock.json', 'dist/index.js'],
+      {...baseManifest, version: '1.0.1', dependencies: {runtime: '1.1.0'}}
+    ],
+    [
+      ['package.json', 'package-lock.json', 'dist/index.js', 'CODEOWNERS'],
+      {...baseManifest, dependencies: {runtime: '1.1.0'}}
+    ]
+  ])('creates a draft minor for behavioral changes: %j', (files, manifest) => {
+    expect(classify(files as string[], manifest).kind).toBe('minor')
+  })
+
+  it('fails closed when source changes without a rebuilt bundle', () => {
+    expect(classify(['src/index.ts']).kind).toBe('stale-bundle')
+  })
+})