diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index dfb13cef1130ed430d8795045e3ad4b977e426ca..37c077f3e992771d3a65bb24f78471c5a977f392 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -131,7 +131,7 @@ minimal-windows:
     - env
     - pip list
     - python -c "import numpy"
-    - py.test -v -n $NUM_CORES -m "not (notebook or longrun)"
+    - py.test -v -m "not (notebook or longrun)"
 
 minimal-sympy-master:
   stage: test