diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 7be466db0203ebd7f26b2731ac143d7fb40f4168..8ea5821bc11333b97e4e63feff51cb7ae42db906 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1441,6 +1441,9 @@ clang_12.0_hybrid:
       WALBERLA_BUILD_WITH_CUDA: "OFF"
       WALBERLA_BUILD_WITH_CODEGEN: "ON"
       WALBERLA_BUILD_WITH_PYTHON: "ON"
+   only:
+      variables:
+         - $ENABLE_NIGHTLY_BUILDS
    tags:
       - docker
 
@@ -1460,6 +1463,9 @@ clang_12.0_serial_dbg:
       CMAKE_BUILD_TYPE: "DebugOptimized"
       WALBERLA_BUILD_WITH_CODEGEN: "ON"
       WALBERLA_BUILD_WITH_PYTHON: "ON"
+   only:
+      variables:
+         - $ENABLE_NIGHTLY_BUILDS
    tags:
       - docker
 
@@ -1477,6 +1483,9 @@ clang_12.0_mpionly_dbg:
       WALBERLA_BUILD_WITH_OPENMP: "OFF"
       WALBERLA_BUILD_WITH_CODEGEN: "ON"
       WALBERLA_BUILD_WITH_PYTHON: "ON"
+   only:
+      variables:
+         - $ENABLE_NIGHTLY_BUILDS
    tags:
       - docker
 
@@ -1493,12 +1502,137 @@ clang_12.0_hybrid_dbg:
       CMAKE_BUILD_TYPE: "DebugOptimized"
       WALBERLA_BUILD_WITH_CODEGEN: "ON"
       WALBERLA_BUILD_WITH_PYTHON: "ON"
+   only:
+      variables:
+         - $ENABLE_NIGHTLY_BUILDS
    tags:
       - docker
 
 clang_12.0_hybrid_dbg_sp:
    extends: .build_template
    image: i10git.cs.fau.de:5005/walberla/buildenvs/clang:12.0
+   variables:
+      WALBERLA_BUILD_WITH_CUDA: "OFF"
+      CMAKE_BUILD_TYPE: "DebugOptimized"
+      WALBERLA_DOUBLE_ACCURACY: "OFF"
+      WALBERLA_BUILD_WITH_PARMETIS: "OFF"
+      WALBERLA_BUILD_WITH_METIS: "OFF"
+   only:
+      variables:
+         - $ENABLE_NIGHTLY_BUILDS
+   tags:
+      - docker
+
+clang_13.0_serial:
+   extends: .build_template
+   image: i10git.cs.fau.de:5005/walberla/buildenvs/clang:13.0
+   before_script:
+      - pip3 install lbmpy==0.4.1 jinja2 pytest
+      - cd python
+      - python3 -m pytest --junitxml=report.xml pystencils_walberla lbmpy_walberla
+      - cd ..
+   variables:
+      WALBERLA_BUILD_WITH_CUDA: "OFF"
+      WALBERLA_BUILD_WITH_MPI: "OFF"
+      WALBERLA_BUILD_WITH_OPENMP: "OFF"
+      WALBERLA_BUILD_WITH_PARMETIS: "OFF"
+      WALBERLA_BUILD_WITH_CODEGEN: "ON"
+      WALBERLA_BUILD_WITH_PYTHON: "ON"
+   only:
+      variables:
+         - $ENABLE_NIGHTLY_BUILDS
+   tags:
+      - docker
+
+clang_13.0_mpionly:
+   extends: .build_template
+   image: i10git.cs.fau.de:5005/walberla/buildenvs/clang:13.0
+   before_script:
+      - pip3 install lbmpy==0.4.1 jinja2 pytest
+      - cd python
+      - python3 -m pytest --junitxml=report.xml pystencils_walberla lbmpy_walberla
+      - cd ..
+   variables:
+      WALBERLA_BUILD_WITH_CUDA: "OFF"
+      WALBERLA_BUILD_WITH_OPENMP: "OFF"
+      WALBERLA_BUILD_WITH_CODEGEN: "ON"
+      WALBERLA_BUILD_WITH_PYTHON: "ON"
+   only:
+      variables:
+         - $ENABLE_NIGHTLY_BUILDS
+   tags:
+      - docker
+
+clang_13.0_hybrid:
+   extends: .build_template
+   image: i10git.cs.fau.de:5005/walberla/buildenvs/clang:13.0
+   before_script:
+      - pip3 install lbmpy==0.4.1 jinja2 pytest
+      - cd python
+      - python3 -m pytest --junitxml=report.xml pystencils_walberla lbmpy_walberla
+      - cd ..
+   variables:
+      WALBERLA_BUILD_WITH_CUDA: "OFF"
+      WALBERLA_BUILD_WITH_CODEGEN: "ON"
+      WALBERLA_BUILD_WITH_PYTHON: "ON"
+   tags:
+      - docker
+
+clang_13.0_serial_dbg:
+   extends: .build_template
+   image: i10git.cs.fau.de:5005/walberla/buildenvs/clang:13.0
+   before_script:
+      - pip3 install lbmpy==0.4.1 jinja2 pytest
+      - cd python
+      - python3 -m pytest --junitxml=report.xml pystencils_walberla lbmpy_walberla
+      - cd ..
+   variables:
+      WALBERLA_BUILD_WITH_CUDA: "OFF"
+      WALBERLA_BUILD_WITH_MPI: "OFF"
+      WALBERLA_BUILD_WITH_OPENMP: "OFF"
+      WALBERLA_BUILD_WITH_PARMETIS: "OFF"
+      CMAKE_BUILD_TYPE: "DebugOptimized"
+      WALBERLA_BUILD_WITH_CODEGEN: "ON"
+      WALBERLA_BUILD_WITH_PYTHON: "ON"
+   tags:
+      - docker
+
+clang_13.0_mpionly_dbg:
+   extends: .build_template
+   image: i10git.cs.fau.de:5005/walberla/buildenvs/clang:13.0
+   before_script:
+      - pip3 install lbmpy==0.4.1 jinja2 pytest
+      - cd python
+      - python3 -m pytest --junitxml=report.xml pystencils_walberla lbmpy_walberla
+      - cd ..
+   variables:
+      WALBERLA_BUILD_WITH_CUDA: "OFF"
+      CMAKE_BUILD_TYPE: "DebugOptimized"
+      WALBERLA_BUILD_WITH_OPENMP: "OFF"
+      WALBERLA_BUILD_WITH_CODEGEN: "ON"
+      WALBERLA_BUILD_WITH_PYTHON: "ON"
+   tags:
+      - docker
+
+clang_13.0_hybrid_dbg:
+   extends: .build_template
+   image: i10git.cs.fau.de:5005/walberla/buildenvs/clang:13.0
+   before_script:
+      - pip3 install lbmpy==0.4.1 jinja2 pytest
+      - cd python
+      - python3 -m pytest --junitxml=report.xml pystencils_walberla lbmpy_walberla
+      - cd ..
+   variables:
+      WALBERLA_BUILD_WITH_CUDA: "OFF"
+      CMAKE_BUILD_TYPE: "DebugOptimized"
+      WALBERLA_BUILD_WITH_CODEGEN: "ON"
+      WALBERLA_BUILD_WITH_PYTHON: "ON"
+   tags:
+      - docker
+
+clang_13.0_hybrid_dbg_sp:
+   extends: .build_template
+   image: i10git.cs.fau.de:5005/walberla/buildenvs/clang:13.0
    stage: pretest
    variables:
       WALBERLA_BUILD_WITH_CUDA: "OFF"
diff --git a/tests/core/timing/TimingPoolTest.cpp b/tests/core/timing/TimingPoolTest.cpp
index db13dc3bd7e2a6a3fa140de4dada2f61f8ac07b4..cec8b57347afb16c27a5dc0c998780eb09b34dde 100644
--- a/tests/core/timing/TimingPoolTest.cpp
+++ b/tests/core/timing/TimingPoolTest.cpp
@@ -48,7 +48,7 @@ void simpleTiming()
          sum += 1;
       pool["In the loop"].end();
    }
-
+   WALBERLA_UNUSED(sum);
    pool["All Together"].end();
 
    cout << pool << endl;
@@ -68,7 +68,7 @@ void scopedTimer()
          sum += std::asin( std::sin( d ) );
          sum += std::acos( std::cos( d ) );
       }
-
+      WALBERLA_UNUSED(sum);
       pool["normal timer"].end();
    }
 
diff --git a/tests/pde/MGTest.cpp b/tests/pde/MGTest.cpp
index 275a2ecc19150c0300dd96927c9254ddfd9f2da9..9993de251d27260773698b8f9645bd15348d4b8c 100644
--- a/tests/pde/MGTest.cpp
+++ b/tests/pde/MGTest.cpp
@@ -71,6 +71,7 @@ void initU( const shared_ptr< StructuredBlockStorage > & blocks, const BlockData
          sum += u->get( *cell );
       }
    }
+   WALBERLA_UNUSED(sum);
 }