diff --git a/Storage/Hashed/Index.hs b/Storage/Hashed/Index.hs
--- a/Storage/Hashed/Index.hs
+++ b/Storage/Hashed/Index.hs
@@ -53,11 +53,11 @@
 import System.Directory( doesFileExist )
 #if mingw32_HOST_OS
 import System.Directory( renameFile )
+import System.FilePath( (<.>) )
 #else
 import System.Directory( removeFile )
 #endif
 
-import System.FilePath( )
 import Control.Monad( when )
 import Control.Exception.Extensible
 import Control.Applicative( (<$>) )
diff --git a/hashed-storage.cabal b/hashed-storage.cabal
--- a/hashed-storage.cabal
+++ b/hashed-storage.cabal
@@ -1,5 +1,5 @@
 name:          hashed-storage
-version:       0.4.2
+version:       0.4.3
 synopsis:      Hashed file storage support code.
 
 description:   Support code for reading and manipulating hashed file storage
@@ -77,7 +77,7 @@
 
     c-sources: Bundled/sha2.c
 
-    extensions: ScopedTypeVariables, NoMonomorphismRestriction
+    extensions: PatternSignatures, NoMonomorphismRestriction
 
 executable hashed-storage-test
     if impl(ghc >= 6.8)