diff --git a/setup.py b/setup.py
index b2b30b9..6842d63 100755
--- a/setup.py
+++ b/setup.py
@@ -19,7 +19,7 @@ if sys.argv[-1] == 'speedups':
         print('Pip required.')
         sys.exit(1)
 
-    os.system('pip install simplejson pyyaml')
+    os.system('pip install ujson pyyaml')
     sys.exit()
 
 if sys.argv[-1] == 'test':