diff --git a/Blaze/ByteString/Builder/ByteString.hs b/Blaze/ByteString/Builder/ByteString.hs
--- a/Blaze/ByteString/Builder/ByteString.hs
+++ b/Blaze/ByteString/Builder/ByteString.hs
@@ -1,4 +1,4 @@
-{-# LANGUAGE CPP, BangPatterns, OverloadedStrings #-}
+{-# LANGUAGE CPP, BangPatterns, OverloadedStrings, MonoPatBinds #-}
 
 -- |
 -- Module      : Blaze.ByteString.Builder.ByteString
diff --git a/Blaze/ByteString/Builder/Char8.hs b/Blaze/ByteString/Builder/Char8.hs
--- a/Blaze/ByteString/Builder/Char8.hs
+++ b/Blaze/ByteString/Builder/Char8.hs
@@ -1,4 +1,5 @@
 {-# OPTIONS_GHC -fno-warn-unused-imports #-} 
+{-# LANGUAGE MonoPatBinds #-}
 -- ignore warning from 'import Data.Text.Encoding'
 
 -- |
diff --git a/Blaze/ByteString/Builder/HTTP.hs b/Blaze/ByteString/Builder/HTTP.hs
--- a/Blaze/ByteString/Builder/HTTP.hs
+++ b/Blaze/ByteString/Builder/HTTP.hs
@@ -1,4 +1,4 @@
-{-# LANGUAGE BangPatterns, CPP, MagicHash, OverloadedStrings #-}
+{-# LANGUAGE BangPatterns, CPP, MagicHash, OverloadedStrings, MonoPatBinds #-}
 -- | Support for HTTP response encoding.
 --
 -- TODO: Cleanup!
diff --git a/Blaze/ByteString/Builder/Int.hs b/Blaze/ByteString/Builder/Int.hs
--- a/Blaze/ByteString/Builder/Int.hs
+++ b/Blaze/ByteString/Builder/Int.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE MonoPatBinds #-}
 -- |
 -- Module      : Blaze.ByteString.Builder.Int
 -- Copyright   : (c) 2010 Simon Meier
diff --git a/Blaze/ByteString/Builder/Internal/Types.hs b/Blaze/ByteString/Builder/Internal/Types.hs
--- a/Blaze/ByteString/Builder/Internal/Types.hs
+++ b/Blaze/ByteString/Builder/Internal/Types.hs
@@ -1,4 +1,4 @@
-{-# LANGUAGE CPP, BangPatterns, Rank2Types #-}
+{-# LANGUAGE CPP, BangPatterns, Rank2Types, MonoPatBinds #-}
 -- |
 -- Module      : Blaze.ByteString.Builder.Internal.Types
 -- Copyright   : (c) 2010 Simon Meier
diff --git a/Blaze/ByteString/Builder/Internal/UncheckedShifts.hs b/Blaze/ByteString/Builder/Internal/UncheckedShifts.hs
--- a/Blaze/ByteString/Builder/Internal/UncheckedShifts.hs
+++ b/Blaze/ByteString/Builder/Internal/UncheckedShifts.hs
@@ -1,4 +1,4 @@
-{-# LANGUAGE CPP, MagicHash #-}
+{-# LANGUAGE CPP, MagicHash, MonoPatBinds #-}
 -- |
 -- Module      : Blaze.ByteString.Builder.Internal.UncheckedShifts
 -- Copyright   : (c) 2010 Simon Meier
diff --git a/Blaze/ByteString/Builder/Internal/Write.hs b/Blaze/ByteString/Builder/Internal/Write.hs
--- a/Blaze/ByteString/Builder/Internal/Write.hs
+++ b/Blaze/ByteString/Builder/Internal/Write.hs
@@ -1,4 +1,4 @@
-{-# LANGUAGE CPP, BangPatterns #-}
+{-# LANGUAGE CPP, BangPatterns, MonoPatBinds #-}
 -- |
 -- Module      : Blaze.ByteString.Builder.Internal.WriteIO
 -- Copyright   : (c) 2010 Simon Meier
diff --git a/Blaze/ByteString/Builder/Word.hs b/Blaze/ByteString/Builder/Word.hs
--- a/Blaze/ByteString/Builder/Word.hs
+++ b/Blaze/ByteString/Builder/Word.hs
@@ -1,4 +1,4 @@
-{-# LANGUAGE CPP #-}
+{-# LANGUAGE CPP, MonoPatBinds #-}
 -- |
 -- Module      : Blaze.ByteString.Builder.Word
 -- Copyright   : (c) 2010 Jasper Van der Jeugt & Simon Meier
diff --git a/CHANGES b/CHANGES
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,8 @@
+* 0.2.1.2
+
+  - Add 'MonoPatBinds' language extension to all relevant files to solve the
+    issues caused by GHC bug http://hackage.haskell.org/trac/ghc/ticket/4498
+
 * 0.2.1.1
   
   - Reexport 'Write' datatype and 'fromWriteList', 'fromWriteSingleton',
diff --git a/blaze-builder.cabal b/blaze-builder.cabal
--- a/blaze-builder.cabal
+++ b/blaze-builder.cabal
@@ -1,5 +1,5 @@
 Name:                blaze-builder
-Version:             0.2.1.1
+Version:             0.2.1.2
 Synopsis:            Efficient buffered output.
 
 Description: