diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
new file mode 100644
index 0000000..499df19
--- /dev/null
+++ b/.github/workflows/main.yml
@@ -0,0 +1,65 @@
+name: check version number and minify
+
+on:
+  push:
+    paths:
+      - 'coi-serviceworker.js'
+      - 'package.json'
+
+permissions:
+  contents: write
+
+jobs:
+  sync-minify-push:
+    runs-on: ubuntu-latest
+    steps:
+      - name: checkout
+        uses: actions/checkout@v4
+      - name: setup node
+        uses: actions/setup-node@v3
+      - name: git config to enable bot to push
+        run: |
+          git remote set-url origin https://github-actions:${{ secrets.GITHUB_TOKEN }}@github.com/${GITHUB_REPOSITORY}
+          git config --local user.email "github-actions[bot]@users.noreply.github.com"
+          git config --local user.name "github-actions[bot]"
+
+      - name: npm install
+        run: |
+          cp package-lock.json lock-orig
+          npm install
+      - name: push package-lock.json
+        if: ${{ hashFiles('package-lock.json') != hashFiles('lock-orig') }}
+        run: |
+          git add package-lock.json
+          git commit -m "update package-lock.json"
+          git push origin HEAD:${GITHUB_REF}
+
+      - name: get package_version
+        run: |
+          package_version="$(npx -c 'echo $npm_package_version')"
+          echo "package_version=${package_version}" \
+          | grep -E 'package_version=[0-9]+\.[0-9]+\.[0-9]+$' >> "${GITHUB_ENV}"
+      - name: update coi-serviceworker.js
+        run: |
+          cp coi-serviceworker.js js-orig
+          sed -i -E "1s/ v[0-9]+\.[0-9]+\.[0-9]+ / v${package_version} /" coi-serviceworker.js
+      - name: push coi-serviceworker.js
+        if: ${{ hashFiles('coi-serviceworker.js') != hashFiles('js-orig') }}
+        run: |
+          git add coi-serviceworker.js
+          git commit -m "sync version numbers"
+          git push origin HEAD:${GITHUB_REF}
+
+      - name: minify
+        run: |
+          mv coi-serviceworker.min.js min-orig
+          npm run minify
+      - name: push coi-serviceworker.min.js
+        if: ${{ hashFiles('coi-serviceworker.min.js') != hashFiles('min-orig') }}
+        run: |
+          git add coi-serviceworker.min.js
+          git commit -m "minify"
+          git push origin HEAD:${GITHUB_REF}
+
+      - name: git diff
+        run: git diff --exit-code