build(#23): Publish multi-architecture container images

.github/workflows/docker.yml

@@ -18,6 +18,9 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v7
 
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v4
+
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v4
 
@@ -36,6 +39,7 @@ jobs:
           context: .
           file: Dockerfile
           push: false
+          platforms: linux/amd64,linux/arm64
           tags: ${{ steps.meta.outputs.tags }}
           labels: ${{ steps.meta.outputs.labels }}
           cache-from: type=gha

.github/workflows/release.yml

@@ -59,6 +59,9 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v7
 
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v4
+
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v4
 
@@ -85,6 +88,7 @@ jobs:
           context: .
           file: Dockerfile
           push: true
+          platforms: linux/amd64,linux/arm64
           tags: ${{ steps.meta.outputs.tags }}
           labels: ${{ steps.meta.outputs.labels }}
           cache-from: type=gha

README.md

@@ -243,8 +243,9 @@ OpenNetworkDiagram/
 
 ### CI/CD
 
-- `docker.yml`: validates Docker build on pull requests.
-- `release.yml`: semantic release on `main` and Docker Hub publish for tagged releases.
+- `docker.yml`: validates AMD64 and ARM64 Docker builds on pull requests.
+- `release.yml`: semantic release on `main` and multi-platform Docker Hub publish for tagged releases.
+- Published images support AMD64 and 64-bit ARM (including Raspberry Pi systems); Docker selects the matching variant automatically.
 - Docker Hub image: [`jcreek23/open-network-diagram`](https://hub.docker.com/r/jcreek23/open-network-diagram)
 
 ## Contributing