diff --git a/hex.cabal b/hex.cabal
--- a/hex.cabal
+++ b/hex.cabal
@@ -1,5 +1,5 @@
 Name:                hex
-Version:             0.1.1
+Version:             0.1.2
 Synopsis:            Convert strings into hexadecimal and back.
 Description:         Convert strings into hexadecimal and back.
 License:             BSD3
@@ -10,6 +10,6 @@
 Maintainer:          taruti@taruti.net
 Build-Depends:       base >= 3 && < 5, bytestring
 Exposed-modules:     Data.Hex
-Extensions:          TypeSynonymInstances
+Extensions:          TypeSynonymInstances FlexibleInstances
 GHC-Options:         -Wall
 Build-Type:	     Simple