test8

.github/workflows/main.yaml

@@ -21,23 +21,27 @@ jobs:
     - name: Install uv
       uses: astral-sh/setup-uv@4db96194c378173c656ce18a155ffc14a9fc4355
 
-    - name: Set cache key
-      id: cache_key
-      # v1 uses a different input
+    - name: Calculate cache key content hash
+      id: cache_content_key
+      # Because we want to dynamically include matrix.version in the path, we
+      # cannot use GHAs hashFiles construct, and have to DIY it.
       run: |
         if [ "${{ matrix.version }}" = "v1" ]; then
-          cache_key="${{ runner.os }}-${{ matrix.version }}-buildx-${{ hashFiles('v1/renv.lock') }}"
+          # v1 uses renv
+          path="v1/renv.lock"
         else
-          cache_key="${{ runner.os }}-${{ matrix.version }}-buildx-${{ hashFiles(format('{0}/packages.toml', matrix.version)) }}"
+          # v2+ use our custom toml format, in the matrix.version subdir
+          path="${{ matrix.version }}/packages.toml"
         fi
-        echo "cache_key=$cache_key" >> "$GITHUB_OUTPUT"
-        echo "Generated cache key: $cache_key"
+        key=$(sha256sum $path | awk '{print $1}')
+        echo "cache_content_key=$key" >> "$GITHUB_OUTPUT"
+        echo "Generated cache_content_key for $path: $key"
 
     - name: Cache Docker buildx caches
       uses: actions/cache@v4
       with:
-        path: /tmp/.buildx-cache
-        key: ${{ steps.cache_key.outputs.cache_key}}
+        path: /var/lib/buildkit
+        key: ${{ runner.os }}-${{ matrix.version }}-buildx-${{ steps.cache_content_key.outputs.cache_content_key }}
         # fallback to older cache keys if needed
         restore-keys: |
           ${{ runner.os }}-${{ matrix.version }}-buildx-