diff --git a/filepath.cabal b/filepath.cabal
index ac3a101460a06242cff5ea852903ff2846494d52..870556be0ba5d29f829b0ddd1391b2aed7a538ad 100644
--- a/filepath.cabal
+++ b/filepath.cabal
@@ -9,13 +9,13 @@ Category:       System
 build-type:     Simple
 Synopsis:       Library for manipulating FilePath's in a cross platform way.
 cabal-version:  >=1.6
+Extra-Source-Files: System/FilePath/Internal.hs
 
 Library
     Exposed-modules:
         System.FilePath
         System.FilePath.Posix
         System.FilePath.Windows
-    Extra-Source-Files: System/FilePath/Internal.hs
     Extensions: CPP
     Build-Depends:  base