diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 15436ebb09bf3efe868d4a94fece46725e61abe9..6c68a47767ffb2f246496b90204ac68525ea7884 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -110,6 +110,7 @@ build/fedora/33:
   <<: *build
   variables:
     DOCKER_IMAGE: fedora/33
+    RPM_BUILD_NCPUS: '1'
 
 test/fedora/33:
   <<: *test