ci: add arm64 docker builds

.github/workflows/cd-image.yml

@@ -0,0 +1,107 @@
+name: Publish nilchain-devnet to GHCR
+
+on:
+  push:
+    branches:
+      - main
+  workflow_dispatch:
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+permissions:
+  contents: read
+  packages: write # Required to push to GHCR
+
+jobs:
+  build-and-push-arch:
+    runs-on: ${{ matrix.runner }}
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - arch: amd64
+            platform: linux/amd64
+            runner: ubuntu-latest
+          - arch: arm64
+            platform: linux/arm64
+            runner: ubuntu-24.04-arm
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Log in to GitHub Container Registry
+        uses: docker/login-action@v3
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Extract metadata for version
+        id: meta_tag
+        uses: docker/metadata-action@v5
+        with:
+          images: ghcr.io/nillionnetwork/nilchain-devnet
+          tags: |
+            type=ref,event=branch
+            type=ref,event=tag
+            type=sha,prefix=
+          flavor: |
+            latest=false
+
+      - name: Build and push arch-specific image
+        uses: docker/build-push-action@v6
+        with:
+          context: .
+          platforms: ${{ matrix.platform }}
+          push: true
+          tags: ghcr.io/nillionnetwork/nilchain-devnet:${{ github.sha }}-${{ matrix.arch }}
+          build-args: |
+            VERSION=${{ steps.meta_tag.outputs.version }}
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
+          provenance: false
+
+  create-and-push-manifest:
+    runs-on: ubuntu-latest
+    needs: build-and-push-arch
+    steps:
+      - name: Log in to GitHub Container Registry
+        uses: docker/login-action@v3
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Extract final tags
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: ghcr.io/nillionnetwork/nilchain-devnet
+          tags: |
+            type=ref,event=branch
+            type=ref,event=tag
+          flavor: |
+            latest=false
+
+      - name: Create and push multi-arch manifest
+        run: |
+          echo "${{ steps.meta.outputs.tags }}" > tags.txt
+
+          while IFS= read -r tag; do
+            if [ -n "$tag" ]; then
+              echo "Creating and pushing manifest for tag: $tag"
+
+              docker manifest create "$tag" \
+                ghcr.io/nillionnetwork/nilchain-devnet:${{ github.sha }}-amd64 \
+                ghcr.io/nillionnetwork/nilchain-devnet:${{ github.sha }}-arm64
+
+              docker manifest push "$tag"
+            fi
+          done < tags.txt

Dockerfile

@@ -1,4 +1,4 @@
-FROM ghcr.io/nillionnetwork/nilchaind:v0.2.5
+FROM ghcr.io/nillionnetwork/nilchaind:main
 
 WORKDIR /opt/nilchain