diff --git a/Makefile b/Makefile
index f5ca6b85..9e971e41 100644
--- a/Makefile
+++ b/Makefile
@@ -265,7 +265,7 @@ endif
 endif
 
 # Make tools if out of date
-DUMMY != CC=$(CC) CXX=$(CXX) $(MAKE) -C tools >&2 || echo FAIL
+DUMMY != CC=$(CC) CXX=$(CXX) $(MAKE) -C tools -j1 >&2 || echo FAIL
 ifeq ($(DUMMY),FAIL)
   $(error Failed to build tools)
 endif