diff --git a/System/FilePath/Manip.hs b/System/FilePath/Manip.hs
index 4b721a8..01308d1 100644
--- a/System/FilePath/Manip.hs
+++ b/System/FilePath/Manip.hs
@@ -1,4 +1,4 @@
-{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE FlexibleInstances, TypeSynonymInstances #-}
 
 -- |
 -- Module:      System.FilePath.Manip