diff --git a/academic/reduce-algebra/reduce-algebra.SlackBuild b/academic/reduce-algebra/reduce-algebra.SlackBuild
index d7189bf41b..f1bae815de 100644
--- a/academic/reduce-algebra/reduce-algebra.SlackBuild
+++ b/academic/reduce-algebra/reduce-algebra.SlackBuild
@@ -82,7 +82,7 @@ sed --in-place "s/^echo\ \$os$/echo $SLACKVER/" scripts/findos.sh
 CFLAGS="$SLKCFLAGS" CXXFLAGS="$SLKCFLAGS" ./configure --with-csl
 CFLAGS="$SLKCFLAGS" CXXFLAGS="$SLKCFLAGS" ./configure --with-psl
 
-make
+make -j1
 
 # The Makefile has no 'install' target (yet).  Let's do by hand.
 # The below code is mainly based on debianbuild/reduce/debian/rules