optimise build/test WF

.github/workflows/build.yaml

@@ -7,6 +7,7 @@ on:
 
 jobs:
   build:
+    timeout-minutes: 360
     strategy:
       fail-fast: false
       matrix:
@@ -60,6 +61,13 @@ jobs:
           tags: ghcr.io/${{ vars.ORG_REPO }}/${{ github.event.repository.name }}
           outputs: type=image,push-by-digest=true,name-canonical=true,push=true
 
+      - name: Test notebooks
+        shell: bash
+        run: |
+          docker run -t ghcr.io/${{ vars.ORG_REPO }}/${{ github.event.repository.name }}@${{ steps.build.outputs.digest }} bash -c " \
+            pip install pytest nbmake; \
+            find . -name '*.ipynb' | pytest --nbmake --nbmake-timeout=3600;"
+
       - name: Export digest
         run: |
           mkdir -p ${{ runner.temp }}/digests
@@ -74,9 +82,10 @@ jobs:
           if-no-files-found: error
           retention-days: 1
 
-  merge:
+  tags:
+    if: github.event_name != 'pull_request'
     runs-on: ubuntu-24.04
-    name: merge into multiarch manifest
+    name: merge and tag
     needs:
       - build
     steps:
@@ -104,7 +113,9 @@ jobs:
         uses: docker/metadata-action@v5.8.0
         with:
           images: ghcr.io/${{ vars.ORG_REPO }}/${{ github.event.repository.name }}
-          tags: dev
+          tags: |
+            latest
+            ${{ needs.build.outputs.tag }}
 
       - name: Create manifest list and push
         id: annotate
@@ -128,53 +139,7 @@ jobs:
 
       - name: Inspect image
         run: |
-          docker buildx imagetools inspect ghcr.io/${{ vars.ORG_REPO }}/${{ github.event.repository.name }}:dev
-
-  tests:
-    strategy:
-      fail-fast: false
-      matrix:
-        platform:
-          - linux/amd64
-          - linux/arm64
-    runs-on: ${{ matrix.platform == 'linux/amd64' && 'ubuntu-latest' || matrix.platform == 'linux/arm64' && 'ubuntu-24.04-arm' }}
-    name: testing on ${{ matrix.platform }} 
-    timeout-minutes: 360
-    needs: 
-      - build
-      - merge
-    steps:
-
-      - name: Test notebooks
-        shell: bash
-        run: |
-          docker run -t ghcr.io/${{ vars.ORG_REPO }}/${{ github.event.repository.name }}:dev bash -c " \
-            pip install pytest nbmake; \
-            find . -name '*.ipynb' | pytest --nbmake --nbmake-timeout=3600;"
-
-  tags:
-    runs-on: ubuntu-24.04
-    if: github.event_name != 'pull_request'
-    name: add tags
-    needs:
-      - build
-      - tests
-    steps:
-      - name: Authenticate with GHCR
-        id: auth
-        uses: docker/login-action@v3.5.0
-        with:
-          registry: "ghcr.io"
-          username: ${{github.actor}}
-          password: ${{secrets.BUILD_TOKEN}}
-
-      - name: tag release versions
-        shell: bash
-        run: |
-          docker buildx imagetools create \
-            --tag ghcr.io/${{ vars.ORG_REPO }}/${{ github.event.repository.name }}:latest \
-            --tag ghcr.io/${{ vars.ORG_REPO }}/${{ github.event.repository.name }}:${{ needs.build.outputs.tag }} \
-            ghcr.io/${{ vars.ORG_REPO }}/${{ github.event.repository.name }}:dev
+          docker buildx imagetools inspect ghcr.io/${{ vars.ORG_REPO }}/${{ github.event.repository.name }}:latest
 
       - name: Post version update to dash
         uses: peter-evans/repository-dispatch@v3.0.0