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:            0.1.0
+Version:            0.1.1
 Synopsis:           Process extras
 Description:        Extra functionality for the Process library
                     <http://hackage.haskell.org/package/process>.
@@ -19,8 +19,16 @@
   Location:         https://github.com/davidlazar/process-extras
 
 Library
+  ghc-options:      -Wall
+
   Hs-source-dirs:   src
+
   Exposed-modules:
     System.Process.ByteString
     System.Process.Text
-  Build-depends:    base >= 4 && < 5, process, bytestring, text
+
+  Build-depends:
+    base >= 4 && < 5,
+    process,
+    bytestring,
+    text
diff --git a/src/System/Process/ByteString.hs b/src/System/Process/ByteString.hs
--- a/src/System/Process/ByteString.hs
+++ b/src/System/Process/ByteString.hs
@@ -24,13 +24,13 @@
     errM <- newEmptyMVar
 
     -- fork off a thread to start consuming stdout
-    forkIO $ do
+    _ <- forkIO $ do
         out <- B.hGetContents outh
         putMVar outM out
         putMVar outMVar ()
 
     -- fork off a thread to start consuming stderr
-    forkIO $ do
+    _ <- forkIO $ do
         err  <- B.hGetContents errh
         putMVar errM err
         putMVar outMVar ()
diff --git a/src/System/Process/Text.hs b/src/System/Process/Text.hs
--- a/src/System/Process/Text.hs
+++ b/src/System/Process/Text.hs
@@ -25,13 +25,13 @@
     errM <- newEmptyMVar
 
     -- fork off a thread to start consuming stdout
-    forkIO $ do
+    _ <- forkIO $ do
         out <- T.hGetContents outh
         putMVar outM out
         putMVar outMVar ()
 
     -- fork off a thread to start consuming stderr
-    forkIO $ do
+    _ <- forkIO $ do
         err  <- T.hGetContents errh
         putMVar errM err
         putMVar outMVar ()