diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 5f370d44f0d8ebafaf61f9c4f6768f294cdf8d92..ef04416a453111262294f4c1d85026bac986c821 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -60,8 +60,8 @@
   - mkdir -pv build
   - cd build
   - cmake -DCMAKE_BUILD_TYPE=release -DBUILD_DEMOS=ON -DBUILD_TESTS=ON ..
-  - make -j$WOLF_N_PROC
-  - ctest -j$WOLF_N_PROC
+  - make -j$(nproc)
+  - ctest -j$(nproc)
   # run demos
   - ../bin/hello_wolf
   - ../bin/hello_wolf_autoconf