Build the integration worker once per workflow

.github/workflows/integration.yml

@@ -41,7 +41,55 @@ env:
   VGI_RPC_JAVA_REF: 920dc42cb7d7e652d582de7fbb5b0b7ee3836a34
 
 jobs:
+  build-worker:
+    name: Build worker once
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout vgi-java
+        uses: actions/checkout@v4
+
+      - name: Checkout pinned vgi-rpc-java
+        uses: actions/checkout@v4
+        with:
+          repository: Query-farm/vgi-rpc-java
+          ref: ${{ env.VGI_RPC_JAVA_REF }}
+          path: vgi-rpc-java
+
+      - name: Set up JDK 25
+        uses: actions/setup-java@v4
+        with:
+          distribution: temurin
+          java-version: '25'
+
+      - name: Cache Gradle
+        uses: actions/cache@v4
+        with:
+          path: |
+            ~/.gradle/caches
+            ~/.gradle/wrapper
+          key: gradle-${{ runner.os }}-${{ hashFiles('**/*.gradle*', '**/gradle-wrapper.properties') }}
+          restore-keys: gradle-${{ runner.os }}-
+
+      - name: Build example worker
+        run: ./gradlew --no-daemon :vgi-example-worker:installDist
+        env:
+          VGI_RPC_JAVA_DIR: ${{ github.workspace }}/vgi-rpc-java
+
+      # Archive before upload because upload-artifact does not preserve the
+      # executable bit on the generated launcher script.
+      - name: Package worker
+        run: tar -czf vgi-java-worker.tar.gz vgi-example-worker/build/install/vgi-example-worker
+
+      - name: Upload worker
+        uses: actions/upload-artifact@v4
+        with:
+          name: vgi-java-worker-${{ github.sha }}
+          path: vgi-java-worker.tar.gz
+          if-no-files-found: error
+          retention-days: 1
+
   integration:
+    needs: build-worker
     runs-on: ubuntu-latest
     strategy:
       fail-fast: false
@@ -66,35 +114,19 @@ jobs:
           ref: ${{ env.VGI_REF }}
           path: vgi-upstream
 
-      # Build the vgirpc RPC layer from source (composite include) so the worker
-      # picks up the HTTP features the integration suite needs (gzip negotiation,
-      # sticky cookies) ahead of the next published vgirpc release.
-      - name: Checkout pinned vgi-rpc-java
-        uses: actions/checkout@v4
-        with:
-          repository: Query-farm/vgi-rpc-java
-          ref: ${{ env.VGI_RPC_JAVA_REF }}
-          path: vgi-rpc-java
-
       - name: Set up JDK 25
         uses: actions/setup-java@v4
         with:
           distribution: temurin
           java-version: '25'
 
-      - name: Cache Gradle
-        uses: actions/cache@v4
+      - name: Download worker
+        uses: actions/download-artifact@v4
         with:
-          path: |
-            ~/.gradle/caches
-            ~/.gradle/wrapper
-          key: gradle-${{ runner.os }}-${{ hashFiles('**/*.gradle*', '**/gradle-wrapper.properties') }}
-          restore-keys: gradle-${{ runner.os }}-
+          name: vgi-java-worker-${{ github.sha }}
 
-      - name: Build example worker
-        run: ./gradlew --no-daemon :vgi-example-worker:installDist
-        env:
-          VGI_RPC_JAVA_DIR: ${{ github.workspace }}/vgi-rpc-java
+      - name: Extract worker
+        run: tar -xzf vgi-java-worker.tar.gz
 
       - name: Resolve latest haybarn release
         run: |

ci/README.md

@@ -13,10 +13,12 @@ Rather than building the vgi DuckDB extension from source, CI drives a
 runner, published in Haybarn's releases) and installs the **signed** vgi
 extension from the Haybarn community channel:
 
-1. **Build the worker** — `./gradlew :vgi-example-worker:installDist`.
-2. **Checkout the test suite** — `Query-farm/vgi` at a pinned commit; its
+1. **Build the worker once** — a producer job runs
+   `./gradlew :vgi-example-worker:installDist`, archives the generated
+   distribution, and every transport lane downloads that same artifact.
+2. **Checkout the test suite** — `Query-farm/vgi` at `main`; its
    `test/sql/integration/*.test` files are the suite.
-3. **Download the runner** — `haybarn_unittest-linux-amd64.zip` from the pinned
+3. **Download the runner** — `haybarn_unittest-linux-amd64.zip` from the latest
    Haybarn release.
 4. **Preprocess** — the standalone runner links none of the extensions the
    tests gate on, so [`preprocess-require.awk`](preprocess-require.awk) rewrites