Fist try on full GH builders

.github/workflows/image-release.yml

@@ -39,7 +39,14 @@ on:
 
 jobs:
   release:
-    runs-on: [self-hosted, ARM64, stable]
+    runs-on: ${{ matrix.builder }}
+    strategy:
+      matrix:
+        include:
+          - builder: ubuntu-latest
+            platform: linux/amd64
+          - builder: ubuntu-24.04-arm
+            platform: linux/arm64
     environment: DOCKER_HUB
     steps:
       - name: Checkout
@@ -78,13 +85,80 @@ jobs:
           password: ${{ secrets.registry-password }}
 
       - name: Build and push
+        id: build
         uses: docker/build-push-action@v6
         with:
-          platforms: ${{ inputs.platforms }}
+          platforms: ${{ matrix.platform }}
           context: ${{ inputs.context }}
           file: ${{ inputs.dockerfile }}
           build-args: |
             VOLTO_VERSION=${{ inputs.volto-version }}
-          push: ${{ github.event_name != 'pull_request' }}
+          # push: ${{ github.event_name != 'pull_request' }}
           tags: ${{ steps.meta.outputs.tags }}
           labels: ${{ steps.meta.outputs.labels }}
+          outputs: type=image,push-by-digest=true,name-canonical=true,push=true
+
+      - name: Export digest
+        run: |
+          mkdir -p ${{ runner.temp }}/digests
+          digest="${{ steps.build.outputs.digest }}"
+          touch "${{ runner.temp }}/digests/${digest#sha256:}"
+
+      - name: Upload digest
+        uses: actions/upload-artifact@v4
+        with:
+          name: digests-${{ matrix.platform }}
+          path: ${{ runner.temp }}/digests/*
+          if-no-files-found: error
+          retention-days: 1
+
+  merge:
+    runs-on: ubuntu-latest
+    needs:
+      - release
+    steps:
+      - name: Download digests
+        uses: actions/download-artifact@v4
+        with:
+          path: ${{ runner.temp }}/digests
+          pattern: digests-*
+          merge-multiple: true
+
+      - name: Login to Registry
+        uses: docker/login-action@v3
+        with:
+          username: ${{ secrets.registry-username }}
+          password: ${{ secrets.registry-password }}
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Docker meta
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: |
+            ${{ inputs.image-name }}
+          flavor: |
+            latest=false
+            suffix=${{ inputs.suffix }}
+          tags: |
+            type=ref,event=branch
+            type=ref,event=pr
+            type=pep440,pattern={{version}},value=${{ inputs.volto-version }}
+            type=pep440,pattern={{major}}.{{minor}}.{{patch}},value=${{ inputs.volto-version }}
+            type=pep440,pattern={{major}}.{{minor}},value=${{ inputs.volto-version }}
+            type=pep440,pattern={{major}},value=${{ inputs.volto-version }}
+            type=sha
+            type=raw,value=latest,enable=${{ inputs.is-latest }}
+            type=raw,value=${{ inputs.volto-version }}
+
+      - name: Create manifest list and push
+        working-directory: ${{ runner.temp }}/digests
+        run: |
+          docker buildx imagetools create $(jq -cr '.tags | map("-t " + .) | join(" ")' <<< "$DOCKER_METADATA_OUTPUT_JSON") \
+            $(printf '${{ inputs.image-name }}@sha256:%s ' *)
+
+      - name: Inspect image
+        run: |
+          docker buildx imagetools inspect ${{ inputs.image-name }}:${{ steps.meta.outputs.version }}