diff --git a/Data/RefSerialize/Serialize.hs b/Data/RefSerialize/Serialize.hs
--- a/Data/RefSerialize/Serialize.hs
+++ b/Data/RefSerialize/Serialize.hs
@@ -1,9 +1,10 @@
-{-# OPTIONS -XOverlappingInstances
-            -XTypeSynonymInstances
-            -XFlexibleInstances
-            -XUndecidableInstances
-            -XOverloadedStrings
-            -XNoMonomorphismRestriction
+{-# LANGUAGE OverlappingInstances
+            ,TypeSynonymInstances
+            ,FlexibleInstances
+            ,UndecidableInstances
+            ,OverloadedStrings
+            ,NoMonomorphismRestriction
+            ,BangPatterns
               #-}
 module Data.RefSerialize.Serialize where
 import GHC.Exts
@@ -20,7 +21,29 @@
 import Data.Ord
 import Data.Monoid
 
+-- All this for myToStrict for compatibility with older versions of bytestring that
+-- lack a "toStrict" call
+import qualified Data.ByteString        as S  -- S for strict (hmm...)
+import qualified Data.ByteString.Internal as S
+import qualified Data.ByteString.Unsafe as S
+import Data.ByteString.Lazy.Internal
+import Foreign.ForeignPtr       (withForeignPtr)
+import Foreign.Ptr
 
+
+myToStrict :: ByteString -> S.ByteString
+myToStrict Empty           = S.empty
+myToStrict (Chunk c Empty) = c
+myToStrict cs0 = S.unsafeCreate totalLen $ \ptr -> go cs0 ptr
+  where
+    totalLen = foldlChunks (\a c -> a + S.length c) 0 cs0
+
+    go Empty                        !_       = return ()
+    go (Chunk (S.PS fp off len) cs) !destptr =
+      withForeignPtr fp $ \p -> do
+        S.memcpy destptr (p `plusPtr` off) (fromIntegral len)
+        go cs (destptr `plusPtr` len)
+
 type MFun=  Char -- usafeCoherced to char to store simply the address of the function
 type VarName = String
 data ShowF= Expr ByteString | Var Int  deriving Show
@@ -82,7 +105,7 @@
 
 readContext :: ByteString -> ByteString -> (ByteString, ByteString)
 readContext pattern str=
-  let (s1,s2)= breakOn (toStrict pattern) str
+  let (s1,s2)= breakOn (myToStrict pattern) str
   in  (s1, B.drop (fromIntegral $ B.length pattern) s2)
 
 --readContext pattern str= readContext1  mempty str where
diff --git a/RefSerialize.cabal b/RefSerialize.cabal
--- a/RefSerialize.cabal
+++ b/RefSerialize.cabal
@@ -1,5 +1,5 @@
 name:                RefSerialize
-version:             0.3.1.2
+version:             0.3.1.3
 synopsis:            Write to and read from ByteStrings maintaining internal memory references
 description:
                      Read, Show and Binary instances do not check for internal data references to the same address.
@@ -9,8 +9,13 @@
                      data is very typical in a pure language such is Haskell, this means that the resulting data loose the beatiful
                      economy of space and processing time that referential transparency permits.
                      .
-                     In this release deserialization is much, much faster by using the stringsearch package
+                     In this release:
                      .
+                     Compatibility with older versions of bytestring that have no 'toStrict' call
+                     .
+                     deserialization is much, much faster by using the stringsearch package
+                     .
+
                      See "Data.RefSerialize" for details