diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 21e44c0..b27f6a9 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -13,7 +13,7 @@ test:
   - apt-get install -y --no-install-recommends python3-dev python3-pip python3-coverage python3-setuptools build-essential
   - pip3 install wheel
   - pip3 install -r requirements.txt
-  - su - matemat python3-coverage run --branch -m unittest discover matemat
+  - su - matemat -c 'python3-coverage run --branch -m unittest discover matemat'
   - python3-coverage report -m --include 'matemat/*' --omit '*/test_*.py'
 
 codestyle: