diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 04673e6071da09c85d91a171958cb4ad2b0b7e30..d793d5149a5442aa11573b52afab752a464f18e9 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -109,6 +109,7 @@ build/fedora/33:
   <<: *build
   variables:
     DOCKER_IMAGE: fedora/33
+    RPM_BUILD_NCPUS: '1'
 
 test/fedora/33:
   <<: *test