diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index b1c67fce2245c0213036666861a7c513e4fc0731..a330108f451a33d31b8ccb8cfc8619cb1acc366c 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -76,6 +76,7 @@ install_and_test_311:
   stage: test
   script:
     - pip3 install cython
+    - cythonize -i ltfatpy/comp/*.pyx
     - pip3 install -e . --no-deps
     - python3 -m pytest
   artifacts: