diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 758bfe2..82a4a02 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -1,6 +1,7 @@
 name: Container Images from PostgreSQL sources
 
 on:
+  pull_request:
   workflow_dispatch:
     inputs:
       pg_repo:
@@ -28,6 +29,44 @@ defaults:
     shell: 'bash -Eeuo pipefail -x {0}'
 
 jobs:
+  test-forks:
+    name: test-forks
+    runs-on: ubuntu-24.04
+    steps:
+      - name: Checkout Code
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Git
+        run: |
+          image_tag=$( (git symbolic-ref -q --short HEAD || git describe --tags --exact-match) | tr / -)
+          echo $image_tag
+
+  test-slash:
+    name: test-slash
+    runs-on: ubuntu-24.04
+    steps:
+      - name: Resolve Git reference
+        uses: xt0rted/pull-request-comment-branch@v3
+        id: refs
+
+      - name: Checkout Code
+        uses: actions/checkout@v4
+        with:
+          ref: ${{ steps.refs.outputs.head_sha }}
+          fetch-depth: 0
+
+      - name: Dump GitHub context
+        env:
+          GITHUB_CONTEXT: ${{ toJSON(github) }}
+        run: echo "$GITHUB_CONTEXT"
+
+      - name: Git
+        run: |
+          image_tag=$( (git symbolic-ref -q --short HEAD || git describe --tags --exact-match) | tr / -)
+          echo $image_tag
+
   build-pg:
     name: Build generic PostgreSQL image from sources
     runs-on: ubuntu-24.04