diff --git a/.circleci/config.yml b/.circleci/config.yml
deleted file mode 100644
index 20abfa9..0000000
--- a/.circleci/config.yml
+++ /dev/null
@@ -1,182 +0,0 @@
-version: 2.1
-commands:
-  setup:
-    description: "Setup environment"
-    steps:
-      - run: |
-          composer self-update --stable
-  install_civicrm:
-    description: "Install CiviCRM"
-    parameters:
-      build_name:
-        type: string
-        default: master
-      type:
-        type: string
-        default: drupal-clean
-      version:
-        type: string
-        default: master
-      url:
-        type: string
-        default: http://localhost:8080
-    steps:
-      - run: |
-          civiver=<< parameters.version >>
-          if [[ "$civiver" == "stable" ]]; then
-            civiver=$(curl -s 'https://latest.civicrm.org/stable.php')
-          fi
-          su - buildkit -c "/buildkit/bin/civibuild create << parameters.build_name >> --civi-ver $civiver --type << parameters.type >> --url << parameters.url >>"
-  install_dependencies:
-    description: "Install Dependencies"
-    parameters:
-      build_name:
-        type: string
-        default: master
-    steps:
-      - run: |
-          EXT_DIR=/buildkit/build/<< parameters.build_name >>/web/sites/default/files/civicrm/ext
-          cd $EXT_DIR
-          git clone https://github.com/Project60/org.project60.sepa.git
-          git clone https://github.com/Project60/org.project60.banking.git
-          git clone https://lab.civicrm.org/extensions/mjwshared.git
-          git clone https://github.com/greenpeace-cee/adyen.git -b main
-          chown buildkit:buildkit org.project60.sepa org.project60.banking mjwshared adyen -R
-          su - buildkit -c "cd /buildkit/build/<< parameters.build_name >>/web && cv en org.project60.sepa org.project60.banking mjwshared adyen"
-  install_extension:
-    description: "Install Extension"
-    parameters:
-      build_name:
-        type: string
-        default: master
-    steps:
-      - run: |
-          EXT_DIR=/buildkit/build/<< parameters.build_name >>/web/sites/default/files/civicrm/ext/$CIRCLE_PROJECT_REPONAME
-          cp /root/project $EXT_DIR -r
-          chown buildkit:buildkit $EXT_DIR -R
-          cd $EXT_DIR
-          su - buildkit -c "cd /buildkit/build/<< parameters.build_name >>/web && cv en $CIRCLE_PROJECT_REPONAME"
-  run_civilint:
-    description: "Run civilint"
-    parameters:
-      build_name:
-        type: string
-        default: master
-    steps:
-      - run: su - buildkit -c "cd /buildkit/build/<< parameters.build_name >>/web/sites/default/files/civicrm/ext/$CIRCLE_PROJECT_REPONAME && find . -type f -not -path './vendor/*' | civilint"
-  run_phpunit:
-    description: "Run PHPUnit"
-    parameters:
-      build_name:
-        type: string
-        default: master
-    steps:
-      - run: |
-          mkdir -p /phpunit
-          chown buildkit:buildkit /phpunit
-          su - buildkit -c "cd /buildkit/build/<< parameters.build_name >>/web/sites/default/files/civicrm/ext/$CIRCLE_PROJECT_REPONAME && /buildkit/bin/phpunit9 --log-junit /phpunit/<< parameters.build_name >>/junit.xml"
-  run_all:
-    description: "Run all steps"
-    parameters:
-      build_name:
-        type: string
-        default: master
-      type:
-        type: string
-        default: drupal-clean
-      version:
-        type: string
-        default: master
-      url:
-        type: string
-        default: http://localhost:8080
-    steps:
-      - install_civicrm:
-          build_name: << parameters.build_name >>
-          type: << parameters.type >>
-          version: << parameters.version >>
-          url: << parameters.url >>
-      - install_dependencies:
-          build_name: << parameters.build_name >>
-      - install_extension:
-          build_name: << parameters.build_name >>
-      - run_civilint:
-          build_name: << parameters.build_name >>
-      - run_phpunit:
-          build_name: << parameters.build_name >>
-      - store_test_results:
-          path: /phpunit
-      - store_artifacts:
-          path: /phpunit
-
-executors:
-  civicrm:
-    docker:
-      - image: michaelmcandrew/civicrm-buildkit
-        name: civicrm
-        environment:
-          TERM: xterm-color
-          APACHE_RUN_USER: buildkit
-      - image: mysql:5.7
-        name: mysql
-        environment:
-          MYSQL_ROOT_PASSWORD: buildkit
-      - image: maildev/maildev
-        name: maildev
-
-jobs:
-  build_mysql_5_7:
-    executor: civicrm
-    steps:
-      - setup
-      - checkout
-      - run_all
-      - run_all:
-          build_name: civi-stable
-          version: "stable"
-          url: http://localhost:8081
-      - run_all:
-          build_name: civi-5.69
-          version: "5.69"
-          url: http://localhost:8082
-      - run_all:
-          build_name: civi-5.57
-          version: "5.57"
-          url: http://localhost:8083
-  build_mariadb_10_6:
-    executor: civicrm
-    docker:
-      - image: michaelmcandrew/civicrm-buildkit
-        name: civicrm
-        environment:
-          TERM: xterm-color
-          APACHE_RUN_USER: buildkit
-      - image: mariadb:10.6
-        name: mysql
-        environment:
-          MYSQL_ROOT_PASSWORD: buildkit
-      - image: maildev/maildev
-        name: maildev
-    steps:
-      - setup
-      - checkout
-      - run_all
-      - run_all:
-          build_name: civi-stable
-          version: "stable"
-          url: http://localhost:8081
-      - run_all:
-          build_name: civi-5.69
-          version: "5.69"
-          url: http://localhost:8082
-      - run_all:
-          build_name: civi-5.57
-          version: "5.57"
-          url: http://localhost:8083
-
-workflows:
-  version: 2
-  build:
-    jobs:
-      - build_mysql_5_7
-      - build_mariadb_10_6
diff --git a/.github/workflows/unit-tests.yml b/.github/workflows/unit-tests.yml
new file mode 100644
index 0000000..b2714e4
--- /dev/null
+++ b/.github/workflows/unit-tests.yml
@@ -0,0 +1,82 @@
+name: "Run unit tests"
+
+on: ["push"]
+
+env:
+  CIVI_CI_CIVICRM: ${{ vars.CIVI_CI_CIVICRM || '["master"]' }}
+  CIVI_CI_MYSQL: ${{ vars.CIVI_CI_MYSQL || '["8.0"]' }}
+  CIVI_CI_OS: ${{ vars.CIVI_CI_OS || '["ubuntu-22.04"]' }}
+  CIVI_CI_PHP: ${{ vars.CIVI_CI_PHP || '["8.1"]' }}
+  CIVI_CI_BUILD_TYPE: ${{ vars.CIVI_CI_BUILD_TYPE || '["drupal-clean"]' }}
+  CIVI_CI_EXCLUDES: ${{ vars.CIVI_CI_EXCLUDES || '' }}
+
+jobs:
+  setup-matrix:
+    runs-on: ubuntu-latest
+    outputs:
+      matrix: ${{ steps.setup-matrix.outputs.matrix }}
+    steps:
+      - id: setup-matrix
+        uses: druzsan/setup-matrix@v2
+        with:
+          matrix: |
+            civicrm: ${{ env.CIVI_CI_CIVICRM }}
+            mysql: ${{ env.CIVI_CI_MYSQL }}
+            os: ${{ env.CIVI_CI_OS }}
+            php: ${{ env.CIVI_CI_PHP }}
+            build-type: ${{ env.CIVI_CI_BUILD_TYPE }}
+            exclude: ${{ env.CIVI_CI_EXCLUDES }}
+
+  run-tests:
+    needs: setup-matrix
+    strategy:
+      fail-fast: false
+      matrix: ${{ fromJson(needs.setup-matrix.outputs.matrix) }}
+    runs-on: "${{ matrix.os }}"
+
+    services:
+      mysql:
+        image: "mysql:${{ matrix.mysql }}"
+        env:
+          MYSQL_ALLOW_EMPTY_PASSWORD: "yes"
+        ports:
+          - "3306:3306"
+        options: >-
+          --health-cmd="mysqladmin ping"
+          --health-interval="10s"
+          --health-timeout="5s"
+          --health-retries="3"
+
+    steps:
+      - id: clone-repo
+        name: "Clone the repository"
+        uses: "actions/checkout@v3"
+        with:
+          ref: "${{ github.ref_name }}"
+          path: "de.systopia.contract"
+      - id: build-ci
+        uses: greenpeace-cee/civi-ci@main
+        with:
+          extension: de.systopia.contract
+          civicrm: ${{ matrix.civicrm }}
+          php: ${{ matrix.php }}
+          build-type: ${{ matrix.build-type }}
+      - id: install-extension
+        name: "Install Extension"
+        env:
+          EXT_DIR: ${{ steps.build-ci.outputs.ext-dir }}
+        run: |
+          PATH="/home/runner/buildkit/bin:$PATH"
+          cd "$EXT_DIR"
+          cp -R "$GITHUB_WORKSPACE/de.systopia.contract" "$EXT_DIR/de.systopia.contract"
+          git clone https://github.com/Project60/org.project60.banking.git "$EXT_DIR/org.project60.banking"
+          git clone https://github.com/Project60/org.project60.sepa.git "$EXT_DIR/org.project60.sepa"
+          cv en de.systopia.contract
+      - id: run-tests
+        name: "Run Tests"
+        env:
+          EXT_DIR: ${{ steps.build-ci.outputs.ext-dir }}
+        run: |
+          PATH="/home/runner/buildkit/bin:$PATH"
+          cd "$EXT_DIR/de.systopia.contract"
+          CIVICRM_UF="UnitTests" phpunit9