diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index b8c75ccb..811cedcf 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -16,7 +16,7 @@ jobs:
       run: composer install --prefer-dist --no-dev
 
   PHPunit:
-    name: PHP ${{ matrix.php-versions }} unit tests on ${{ matrix.operating-system }}
+    name: PHP ${{ matrix.php-versions }} unit tests
     runs-on: ubuntu-latest
     # https://docs.github.com/en/actions/using-jobs/using-a-matrix-for-your-jobs#handling-failures
     continue-on-error: "${{ matrix.experimental }}"
@@ -75,6 +75,7 @@ jobs:
     - name: Get composer cache directory
       id: composer-cache
       run: echo "dir=$(composer config cache-files-dir)" >> $GITHUB_OUTPUT
+
     # http://man7.org/linux/man-pages/man1/date.1.html
     # https://github.com/actions/cache#creating-a-cache-key
     - name: Get Date
@@ -111,6 +112,97 @@ jobs:
         name: Test Results (PHP ${{ matrix.php-versions }})
         path: tst/results.xml
 
+  PHPunitConfigCombinations:
+    name: PHP configuration combination unit tests
+    runs-on: ubuntu-latest
+    env:
+      php-version: '8.4'
+      extensions: gd, sqlite3
+      extensions-cache-key-name: phpextensions
+
+    steps:
+
+    # let's get started!
+    - name: Checkout
+      uses: actions/checkout@v4
+
+    # cache PHP extensions
+    - name: Setup cache environment
+      id: extcache
+      uses: shivammathur/cache-extensions@v1
+      with:
+        php-version: ${{ env.php-version }}
+        extensions: ${{ env.extensions }}
+        key: ${{ runner.os }}-${{ env.extensions-cache-key }}
+
+    - name: Cache extensions
+      uses: actions/cache@v4
+      with:
+        path: ${{ steps.extcache.outputs.dir }}
+        key: ${{ steps.extcache.outputs.key }}
+        restore-keys: ${{ runner.os }}-${{ env.extensions-cache-key }}
+
+    - name: Setup PHP
+      uses: shivammathur/setup-php@v2
+      with:
+        php-version: ${{ env.php-version }}
+        extensions: ${{ env.extensions }}
+
+    # Setup GitHub CI PHP problem matchers
+    # https://github.com/shivammathur/setup-php#problem-matchers
+    - name: Setup problem matchers for PHP
+      run: echo "::add-matcher::${{ runner.tool_cache }}/php.json"
+
+    - name: Setup problem matchers for PHPUnit
+      run: echo "::add-matcher::${{ runner.tool_cache }}/phpunit.json"
+
+    # composer cache
+    - name: Remove composer lock
+      run: rm composer.lock
+
+    - name: Get composer cache directory
+      id: composer-cache
+      run: echo "dir=$(composer config cache-files-dir)" >> $GITHUB_OUTPUT
+
+    # http://man7.org/linux/man-pages/man1/date.1.html
+    # https://github.com/actions/cache#creating-a-cache-key
+    - name: Get Date
+      id: get-date
+      run: echo "date=$(/bin/date -u "+%Y%m%d")" >> $GITHUB_OUTPUT
+      shell: bash
+
+    - name: Cache dependencies
+      uses: actions/cache@v4
+      with:
+        path: "${{ steps.composer-cache.outputs.dir }}"
+        key: "${{ runner.os }}-composer-${{ steps.get-date.outputs.date }}-${{ hashFiles('**/composer.json') }}"
+        restore-keys: "${{ runner.os }}-composer-${{ steps.get-date.outputs.date }}-"
+
+    # composer installation
+    - name: Unset platform requirement
+      run: composer config --unset platform
+
+    - name: Setup PHPunit
+      run: composer install -n
+
+    - name: Install Google Cloud Storage
+      run: composer require google/cloud-storage
+
+    # testing
+    - name: Generate configuration combination unit tests
+      run: bin/configuration-test-generator
+
+    - name: Run unit tests
+      run: ../vendor/bin/phpunit --no-coverage --log-junit results.xml ConfigurationCombinationsTest.php
+      working-directory: tst
+
+    - name: Upload Test Results
+      if: always()
+      uses: actions/upload-artifact@v4
+      with:
+        name: Test Results
+        path: tst/results.xml
+
   Mocha:
     runs-on: ubuntu-latest
     steps: