diff --git a/basis/cocoa/subclassing/subclassing.factor b/basis/cocoa/subclassing/subclassing.factor
index 3b88a8868c..62916e45a1 100644
--- a/basis/cocoa/subclassing/subclassing.factor
+++ b/basis/cocoa/subclassing/subclassing.factor
@@ -48,7 +48,7 @@ IN: cocoa.subclassing
 : prepare-methods ( methods -- methods )
     [
         [ first4 prepare-method 3array ] map
-    ] with-compilation-unit ;
+    ] with-nested-compilation-unit ;
 
 :: (redefine-objc-method) ( class method -- )
     method init-method :> ( sel imp types )