diff --git a/process-extras.cabal b/process-extras.cabal
--- a/process-extras.cabal
+++ b/process-extras.cabal
@@ -1,5 +1,5 @@
 Name:               process-extras
-Version:            0.4
+Version:            0.4.1
 Synopsis:           Process extras
 Description:        Extends <http://hackage.haskell.org/package/process>.
                     Read process input and output as ByteStrings or
diff --git a/src/System/Process/Common.hs b/src/System/Process/Common.hs
--- a/src/System/Process/Common.hs
+++ b/src/System/Process/Common.hs
@@ -33,7 +33,7 @@
 import Utils (forkWait)
 
 #if __GLASGOW_HASKELL__ <= 709
-import Control.Applicative (pure, (<$>), (<*>))
+import Control.Applicative ((<$>), (<*>))
 import Data.Monoid (Monoid(mempty, mappend))
 #endif
 
@@ -142,7 +142,7 @@
        do -- fork off a thread to start consuming stdout
           -- Without unsafeIntereleaveIO the pid messsage gets stuck
           -- until some additional output arrives from the process.
-          waitOut <- forkWait $ (<>) <$> pure (pidf pid)
+          waitOut <- forkWait $ (<>) <$> return (pidf pid)
                                      <*> unsafeInterleaveIO (readInterleaved [(outf, outh), (errf, errh)] (codef <$> waitForProcess pid))
           writeInput inh input
           waitOut)
@@ -199,4 +199,4 @@
 -- before they have read all of their input.
 ignoreResourceVanished :: IO () -> IO ()
 ignoreResourceVanished action =
-    action `catch` (\e -> if ioe_type e == ResourceVanished then pure () else ioError e)
+    action `catch` (\e -> if ioe_type e == ResourceVanished then return pure () else ioError e)
diff --git a/src/System/Process/ListLike.hs b/src/System/Process/ListLike.hs
--- a/src/System/Process/ListLike.hs
+++ b/src/System/Process/ListLike.hs
@@ -113,10 +113,10 @@
 
 -- | Send Stdout chunks to stdout and Stderr chunks to stderr.
 writeOutput :: ListLikeIO a c => [Chunk a] -> IO ()
-writeOutput [] = pure ()
+writeOutput [] = return ()
 writeOutput (x : xs) =
-    foldOutput (\_ -> pure ())
+    foldOutput (\_ -> return ())
                (hPutStr stdout)
                (hPutStr stderr)
-               (\_ -> pure ())
-               (\_ -> pure ()) x >> writeOutput xs
+               (\_ -> return ())
+               (\_ -> return ()) x >> writeOutput xs