diff --git a/Control/Concurrent/CHP/Arrow.hs b/Control/Concurrent/CHP/Arrow.hs
--- a/Control/Concurrent/CHP/Arrow.hs
+++ b/Control/Concurrent/CHP/Arrow.hs
@@ -65,15 +65,9 @@
 -- I have got this module to work on GHC 6.8 and 6.10 by following the CPP-variant
 -- instructions on this page: http://haskell.org/haskellwiki/Upgrading_packages
 
-#if __GLASGOW_HASKELL__ >= 609
+import Control.Arrow
 import Control.Category
 import Prelude hiding ((.), id)
-#endif
-
-import Control.Arrow
-#if __GLASGOW_HASKELL__ < 610
-                      hiding (pure)
-#endif
 import Control.DeepSeq
 import Control.Monad
 
@@ -204,16 +198,11 @@
 instance Functor (ProcessPipeline a) where
   fmap f x = x >>> arr f
 
-#if __GLASGOW_HASKELL__ >= 609
 instance Category ProcessPipeline where
   (ProcessPipeline q) . (ProcessPipeline p) = ProcessPipeline (p <=> q)
   id = ProcessPipeline CHP.id
-#endif
 
 instance Arrow ProcessPipeline where
-#if __GLASGOW_HASKELL__ < 609
-  (ProcessPipeline p) >>> (ProcessPipeline q) = ProcessPipeline (p <=> q)
-#endif
   arr = ProcessPipeline . CHP.map
 
   first (ProcessPipeline p) = ProcessPipeline $ \in_ out -> do
diff --git a/Control/Concurrent/CHP/Composed.hs b/Control/Concurrent/CHP/Composed.hs
--- a/Control/Concurrent/CHP/Composed.hs
+++ b/Control/Concurrent/CHP/Composed.hs
@@ -11,7 +11,7 @@
 --  * Redistributions in binary form must reproduce the above copyright
 --    notice, this list of conditions and the following disclaimer in the
 --    documentation and/or other materials provided with the distribution.
---  * Neither the name of the University of Kent nor the names of its
+--  * Neither the name of the Neil Brown nor the names of other
 --    contributors may be used to endorse or promote products derived from
 --    this software without specific prior written permission.
 --
@@ -71,7 +71,6 @@
 import Control.Concurrent.CHP.Connect
 import Control.Concurrent.CHP.Connect.TwoDim (FourWay(..))
 import Control.Monad
-import Control.Monad.Trans
 import Data.List (transpose)
 
 -- | A monad for composing together CHP processes in cross-cutting ways; e.g. wiring
@@ -88,9 +87,6 @@
 
 instance MonadCHP Composed where
   liftCHP x = Composed (x >>=)
-
-instance MonadIO Composed where
-  liftIO x = Composed (liftIO x >>=)
 
 instance Functor Composed where
   fmap = liftM
diff --git a/Control/Concurrent/CHP/Console.hs b/Control/Concurrent/CHP/Console.hs
--- a/Control/Concurrent/CHP/Console.hs
+++ b/Control/Concurrent/CHP/Console.hs
@@ -34,7 +34,6 @@
 import Control.Concurrent.STM
 import qualified Control.Exception.Extensible as C
 import Control.Monad
-import Control.Monad.Trans
 --import Data.Maybe
 import System.IO
 
@@ -56,7 +55,7 @@
 consoleProcess :: (ConsoleChans -> CHP ()) -> CHP ()
 consoleProcess mainProc
   = do [cin, cout, cerr] <- replicateM 3 oneToOneChannel
-       tvs@[tvinId, tvoutId, tverrId] <- liftIO $ atomically $ replicateM 3 $ newTVar Nothing
+       tvs@[tvinId, tvoutId, tverrId] <- liftIO_CHP $ atomically $ replicateM 3 $ newTVar Nothing
        runParallel_
          [ inHandler tvinId (writer cin)
          , outHandler tvoutId stdout (reader cout)
@@ -70,16 +69,16 @@
               -- Poison won't do it if the handlers are blocked on input or
               -- output.  Therefore we throw them an exception to "knock them
               -- off" their current action and make them exit.
-              liftIO yield
-              liftIO $ mapM_ killThread ids
+              liftIO_CHP yield
+              liftIO_CHP $ mapM_ killThread ids
          ]
   where
     getId :: TVar (Maybe a) -> CHP a
-    getId tv = liftIO $ atomically $ readTVar tv >>= maybe retry return
+    getId tv = liftIO_CHP $ atomically $ readTVar tv >>= maybe retry return
 
     -- Like liftIO, but turns any caught exceptions into throwing poison
     liftIO' :: IO a -> CHP a
-    liftIO' m = liftIO (liftM Just m `C.catches` handlers)
+    liftIO' m = liftIO_CHP (liftM Just m `C.catches` handlers)
       >>= maybe throwPoison return
       where
         response :: C.Exception e => e -> IO (Maybe a)
@@ -97,9 +96,9 @@
     
     inHandler :: TVar (Maybe ThreadId) -> Chanout Char -> CHP ()
     inHandler tv c
-      = do liftIO $ myThreadId >>= atomically . writeTVar tv . Just
+      = do liftIO_CHP $ myThreadId >>= atomically . writeTVar tv . Just
            if rtsSupportsBoundThreads
-             then (forever $ do ready <- liftIO $ hWaitForInput stdin 100
+             then (forever $ do ready <- liftIO_CHP $ hWaitForInput stdin 100
                                 checkForPoison c
                                 when ready $
                                   liftIO' getChar >>= writeChannel c)
@@ -109,6 +108,6 @@
 
     outHandler :: TVar (Maybe ThreadId) -> Handle -> Chanin Char -> CHP ()
     outHandler tv h c
-      = do liftIO $ myThreadId >>= atomically . writeTVar tv . Just
+      = do liftIO_CHP $ myThreadId >>= atomically . writeTVar tv . Just
            (forever $ readChannel c >>= liftIO' . hPutChar h)
              `onPoisonTrap` poison c
diff --git a/Control/Concurrent/CHP/Test.hs b/Control/Concurrent/CHP/Test.hs
--- a/Control/Concurrent/CHP/Test.hs
+++ b/Control/Concurrent/CHP/Test.hs
@@ -35,8 +35,6 @@
 
 import Control.Arrow
 import Control.Monad
-import Control.Monad.Error (ErrorT, runErrorT, throwError)
-import Control.Monad.Trans (MonadIO)
 import Data.Monoid
 import Data.Unique
 import Test.HUnit (assertFailure, Test(..))
@@ -171,9 +169,15 @@
                                ++ show t
 
 -- | See withCheck.
-newtype CHPTest a = CHPTest (ErrorT String CHP a)
-  deriving (Monad, MonadIO, MonadCHP)
+newtype CHPTest a = CHPTest {runCHPTest :: CHP (Either String a)}
 
+instance Monad CHPTest where
+  return = CHPTest . return . Right
+  m >>= k = CHPTest $ runCHPTest m >>= either (return . Left) (runCHPTest . k)
+
+instance MonadCHP CHPTest where
+  liftCHP = CHPTest . liftM Right
+
 -- | A helper function that allows you to create CHP tests in an assertion style, either
 -- for use with HUnit or QuickCheck 2.
 --
@@ -223,8 +227,8 @@
 -- >                    poison (reader c) -- Shutdown myProc
 -- >                    assertCHPEqual' "1000 values" xs (replicate 1000 42)
 withCheck :: CHP a -> CHPTest () -> CHP CHPTestResult
-withCheck p (CHPTest t) = liftM snd $ (p `onPoisonTrap` return undefined) <||> do
-  er <- runErrorT t
+withCheck p t = liftM snd $ (p `onPoisonTrap` return undefined) <||> do
+  er <- runCHPTest t
   case er of
     Left msg -> return $ CHPTestFail msg
     Right _ -> return CHPTestPass
@@ -236,7 +240,7 @@
 assertCHP :: CHP () -> String -> Bool -> CHPTest ()
 assertCHP comp msg passed
   | passed = return ()
-  | otherwise = liftCHP comp >> CHPTest (throwError msg)
+  | otherwise = liftCHP comp >> CHPTest (return $ Left msg)
 
 -- | Checks that the given values are equal (first is the expected value of the
 -- test, second is the actual value).  If they are equal, the assertion passes and the
diff --git a/chp-plus.cabal b/chp-plus.cabal
--- a/chp-plus.cabal
+++ b/chp-plus.cabal
@@ -1,5 +1,5 @@
 Name:            chp-plus
-Version:         1.2.0
+Version:         1.3.0
 Synopsis:        A set of high-level concurrency utilities built on Communicating Haskell Processes
 License:         BSD3
 License-file:    LICENSE
@@ -18,7 +18,7 @@
 
 Cabal-Version:   >= 1.2.3
 Build-Type:      Simple
-Build-Depends:   base >= 3 && < 5, chp >= 2.0 && < 2.2, containers, deepseq >= 1.1 && < 1.2, extensible-exceptions >= 0.1.1.0, HUnit, mtl, pretty, QuickCheck >= 2, stm
+Build-Depends:   base >= 3 && < 5, chp >= 2.2 && < 2.3, containers, deepseq >= 1.1 && < 1.2, extensible-exceptions >= 0.1.1.0, HUnit, pretty, QuickCheck >= 2, stm
 
 Exposed-modules: Control.Concurrent.CHP.Actions
                  Control.Concurrent.CHP.Arrow
@@ -31,8 +31,8 @@
                  Control.Concurrent.CHP.Console
                  Control.Concurrent.CHP.Test
 
-Extensions:      CPP FlexibleInstances GeneralizedNewtypeDeriving
-                 MultiParamTypeClasses ParallelListComp Rank2Types
+Extensions:      CPP FlexibleInstances MultiParamTypeClasses
+                 ParallelListComp Rank2Types
                  ScopedTypeVariables TypeFamilies 
 
 GHC-Options:     -Wall -auto-all