diff --git a/shelltest.hs b/shelltest.hs
--- a/shelltest.hs
+++ b/shelltest.hs
@@ -1,5 +1,4 @@
-#!/usr/bin/env runhaskell
-{-# LANGUAGE DeriveDataTypeable, TemplateHaskell #-}
+{-# LANGUAGE DeriveDataTypeable, TemplateHaskell, CPP #-}
 {- |
 
 shelltest - a tool for testing command-line programs.
@@ -12,11 +11,6 @@
 
 module Main
 where
--- encoding: we try to handle non-ascii content in test file paths, test
--- commands, and expected test results.  For this we assume 1. ghc 6.12+
--- and 2. that on unix, all file names/arguments/environment variables are
--- utf8 encoded
-import Codec.Binary.UTF8.String as UTF8 (decodeString, encodeString, isUTF8Encoded)
 import Control.Concurrent (forkIO)
 import Control.Concurrent.MVar (newEmptyMVar, putMVar, takeMVar)
 import Control.Monad (liftM,when,unless)
@@ -25,7 +19,6 @@
 import qualified Test.HUnit (Test)
 import System.Console.CmdArgs
 import System.Exit
-import System.Info (os)
 import System.IO (Handle, hGetContents, hPutStr)
 import System.Process (StdStream (CreatePipe), shell, createProcess, CreateProcess (..), waitForProcess, ProcessHandle)
 import Test.Framework (defaultMainWithArgs)
@@ -43,6 +36,8 @@
 import Data.Algorithm.Diff
 import Distribution.PackageDescription.TH (packageVariable, package, pkgVersion)
 
+import PlatformString (fromPlatformString, toPlatformString)
+
 strace :: Show a => a -> a
 strace a = trace (show a) a
 
@@ -360,21 +355,21 @@
       showm = if all_ then showMatcher else showMatcherTrimmed
       trim' = if all_ then id else trim
 
-showDiff :: Args -> (Int,Int) -> [(DI, String)] -> String
+showDiff :: Args -> (Int,Int) -> [(Diff String)] -> String
 showDiff _ _ []                   = ""
-showDiff args@Args{all_=all_,precise=precise} (l,r) ((F, ln) : ds) =
+showDiff args@Args{all_=all_,precise=precise} (l,r) ((First ln) : ds) =
     printf "+%4d " l ++ ln' ++ "\n" ++ showDiff args (l+1,r) ds
     where
       ln' = trim' $ show' ln
       trim' = if all_ then id else trim
       show' = if precise then show else id
-showDiff args@Args{all_=all_,precise=precise} (l,r) ((S, ln) : ds) =
+showDiff args@Args{all_=all_,precise=precise} (l,r) ((Second ln) : ds) =
     printf "-%4d " r ++ ln' ++ "\n" ++ showDiff args (l,r+1) ds
     where
       ln' = trim' $ show' ln
       trim' = if all_ then id else trim
       show' = if precise then show else id
-showDiff args (l,r) ((B, _ ) : ds) = showDiff args (l+1,r+1) ds
+showDiff args (l,r) ((Both _ _) : ds) = showDiff args (l+1,r+1) ds
 
 instance Show Matcher where show = showMatcherTrimmed
 
@@ -447,28 +442,3 @@
                           then new ++ replace' (drop len l)
                           else h : replace' ts
      len = length old
-
--- | A platform string is a string value from or for the operating system,
--- such as a file path or command-line argument (or environment variable's
--- name or value ?). On some platforms (such as unix) these are not real
--- unicode strings but have some encoding such as UTF-8. This alias does
--- no type enforcement but aids code clarity.
-type PlatformString = String
-
--- | Convert a possibly encoded platform string to a real unicode string.
--- We decode the UTF-8 encoding recommended for unix systems
--- (cf http://www.dwheeler.com/essays/fixing-unix-linux-filenames.html)
--- and leave anything else unchanged.
-fromPlatformString :: PlatformString -> String
-fromPlatformString s = if UTF8.isUTF8Encoded s then UTF8.decodeString s else s
-
--- | Convert a unicode string to a possibly encoded platform string.
--- On unix we encode with the recommended UTF-8
--- (cf http://www.dwheeler.com/essays/fixing-unix-linux-filenames.html)
--- and elsewhere we leave it unchanged.
-toPlatformString :: String -> PlatformString
-toPlatformString = case os of
-                     "unix" -> UTF8.encodeString
-                     "linux" -> UTF8.encodeString
-                     "darwin" -> UTF8.encodeString
-                     _ -> id
diff --git a/shelltestrunner.cabal b/shelltestrunner.cabal
--- a/shelltestrunner.cabal
+++ b/shelltestrunner.cabal
@@ -1,6 +1,6 @@
 name:           shelltestrunner
 -- sync with README.md, ANNOUNCE:
-version:        1.2.1
+version:        1.3
 category:       Testing
 synopsis:       A tool for testing command-line programs.
 description:
@@ -16,7 +16,7 @@
 homepage:       http://joyful.com/shelltestrunner
 bug-reports:    mailto:simon@joyful.com
 stability:      stable
-tested-with:    GHC==6.12.3, GHC==7.0.2, GHC==7.2.1, GHC==7.4.1
+tested-with:    GHC==7.4.1, GHC==7.6.1
 cabal-version:  >= 1.6
 build-type:     Simple
 
@@ -25,22 +25,23 @@
 
 executable shelltest
   main-is:        shelltest.hs
+  other modules:  PlatformString
   ghc-options:    -threaded -W -fwarn-tabs
   build-depends:
                  base                 >= 4     && < 5
                 ,cabal-file-th
                 ,filemanip            >= 0.3   && < 0.4
                 ,HUnit                            < 1.3
-                ,cmdargs              >= 0.7   && < 0.10
+                ,cmdargs              >= 0.7   && < 0.11
                 ,directory            >= 1.0
                 ,filepath             >= 1.0
                 ,parsec                           < 3.2
                 ,regex-tdfa           >= 1.1   && < 1.2
                 ,process                          < 1.2
-                ,test-framework       >= 0.3.2 && < 0.6
-                ,test-framework-hunit >= 0.2   && < 0.3
+                ,test-framework       >= 0.3.2 && < 0.9
+                ,test-framework-hunit >= 0.2   && < 0.4
                 ,utf8-string          >= 0.3.5 && < 0.4
-                ,Diff                 >= 0.1   && < 0.2
+                ,Diff                 == 0.2.*
 
 source-repository head
   type:     darcs