diff --git a/extra/newfx/newfx.factor b/extra/newfx/newfx.factor
index e7d92bba58..37c738cd6a 100644
--- a/extra/newfx/newfx.factor
+++ b/extra/newfx/newfx.factor
@@ -1,11 +1,12 @@
 
-USING: kernel sequences assocs qualified circular ;
+USING: kernel sequences assocs qualified circular sets ;
 
 USING: math multi-methods ;
 
 QUALIFIED: sequences
 QUALIFIED: assocs
 QUALIFIED: circular
+QUALIFIED: sets
 
 IN: newfx