diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 9a5953909bcba1a386a304764bd5c9c013ffc155..d2b08a410e3c38b35cce1258dcd726c7021b00a5 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,4 +1,7 @@
 ---
+variables:
+  DUNECI_CMAKE_FLAGS: "-DDUNE_PYTHON_FORCE_PYTHON3=TRUE"
+
 before_script:
   - duneci-install-module https://git.imp.fu-berlin.de/agnumpde/dune-matrix-vector.git
   - duneci-install-module https://git.imp.fu-berlin.de/agnumpde/dune-solvers.git