diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index b5f6331fed26d60c7e7f1080947f0fd8d70b491a..89e54d0607e3e6c8f2fd7919f0b826f79334e527 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -13,7 +13,7 @@ before_script:
   - apt-get update
   - >
     apt-get install -y build-essential python python-pip python-dev git
-    autoconf gsl-bin libgsl-dev wget python-numpy
+    autoconf gsl-bin libgsl-dev wget python-numpy cython
   - pip install --upgrade -r ci/requirements_base.txt
   - chmod +x ci/*.sh