diff --git a/helpful-things/Makefile b/helpful-things/Makefile
index 0cef424..b5be64c 100644
--- a/helpful-things/Makefile
+++ b/helpful-things/Makefile
@@ -1,10 +1,14 @@
 # You can use this makefile in your
 # build directory to drive ninja builds.
 
+processor_count=$(shell grep -c "^processor" /proc/cpuinfo)
+#count=$(shell expr ${processor_count} - 1)
+count=$(shell expr $(processor_count) - 1 )
+
 __primary: test
 
 all:
-	ninja -v -j19 all
+	ninja -v -j${count} all
 
 clean:
 	ninja clean