diff --git a/cbits/byteorder.c b/cbits/byteorder.c
deleted file mode 100644
index ca7058a..0000000
--- a/cbits/byteorder.c
+++ /dev/null
@@ -1,21 +0,0 @@
-/* Sigh. According to the docs for <arpa/inet.h>, htonl() and friends may be
-   implemented as macros only, so I have to re-export functions here to do the
-   conversions. */
-
-#include <arpa/inet.h>
-
-uint32_t iostreams_htonl(uint32_t hostlong) {
-    return htonl(hostlong);
-}
-
-uint16_t iostreams_htons(uint16_t hostshort) {
-    return htons(hostshort);
-}
-
-uint32_t iostreams_ntohl(uint32_t netlong) {
-    return ntohl(netlong);
-}
-
-uint16_t iostreams_ntohs(uint16_t netshort) {
-    return ntohs(netshort);
-}
diff --git a/io-streams-haproxy.cabal b/io-streams-haproxy.cabal
index 85c99e9..e0e2b55 100644
--- a/io-streams-haproxy.cabal
+++ b/io-streams-haproxy.cabal
@@ -17,8 +17,7 @@ copyright:           (c) 2014 Google, Inc. and CONTRIBUTORS
 category:            Network, IO-Streams
 build-type:          Simple
 extra-source-files:
-  CONTRIBUTORS,
-  cbits/byteorder.c
+  CONTRIBUTORS
 
 cabal-version:       >=1.10
 Bug-Reports:         https://github.com/snapframework/io-streams-haproxy/issues
@@ -28,9 +27,8 @@ library
   ghc-prof-options:  -prof -auto-all
   exposed-modules:   System.IO.Streams.Network.HAProxy
   other-modules:     System.IO.Streams.Network.Internal.Address
-  c-sources:         cbits/byteorder.c
 
-  build-depends:     base              >= 4.4 && < 4.8,
+  build-depends:     base              >= 4.5 && < 4.8,
                      attoparsec        >= 0.7 && < 0.13,
                      bytestring        >= 0.9 && < 0.11,
                      io-streams        >= 1.1 && < 1.3,
@@ -47,7 +45,6 @@ test-suite testsuite
   hs-source-dirs:    src test
   Main-is:           TestSuite.hs
   Default-language:  Haskell2010
-  c-sources:         cbits/byteorder.c
 
   ghc-options:       -Wall -fhpc -fwarn-tabs -funbox-strict-fields -threaded
                      -fno-warn-unused-do-bind
@@ -56,7 +53,7 @@ test-suite testsuite
   Other-modules:     System.IO.Streams.Network.HAProxy,
                      System.IO.Streams.Network.HAProxy.Tests
 
-  build-depends:     base              >= 4.4 && < 4.8,
+  build-depends:     base              >= 4.5 && < 4.8,
                      attoparsec        >= 0.7 && < 0.13,
                      bytestring        >= 0.9 && < 0.11,
                      io-streams        >= 1.1 && < 1.3,
diff --git a/src/System/IO/Streams/Network/HAProxy.hs b/src/System/IO/Streams/Network/HAProxy.hs
index 545f9ac..c0b1443 100644
--- a/src/System/IO/Streams/Network/HAProxy.hs
+++ b/src/System/IO/Streams/Network/HAProxy.hs
@@ -1,9 +1,10 @@
 {-# LANGUAGE BangPatterns             #-}
 {-# LANGUAGE DeriveDataTypeable       #-}
-{-# LANGUAGE ForeignFunctionInterface #-}
 {-# LANGUAGE OverloadedStrings        #-}
 {-# LANGUAGE Trustworthy              #-}
 {-# LANGUAGE TupleSections            #-}
+{-# LANGUAGE CApiFFI                  #-}
+{-# LANGUAGE CPP                      #-}
 
 {-|
 
@@ -35,6 +36,8 @@ module System.IO.Streams.Network.HAProxy
   , getSocketType
   ) where
 
+#include "MachDeps.h"
+
 ------------------------------------------------------------------------------
 import           Control.Applicative                        ((<$>), (<|>))
 import           Control.Monad                              (void, when)
@@ -46,7 +49,9 @@ import           Data.ByteString.Char8                      (ByteString)
 import qualified Data.ByteString.Char8                      as S
 import qualified Data.ByteString.Unsafe                     as S
 import           Data.Word                                  (Word16, Word32, Word8)
-import           Foreign.C.Types                            (CUInt (..), CUShort (..))
+#if MIN_VERSION_base(4,7,0)
+import           Data.Word                                  (byteSwap16, byteSwap32)
+#endif
 import           Foreign.Ptr                                (castPtr)
 import           Foreign.Storable                           (peek)
 import qualified Network.Socket                             as N
@@ -323,14 +328,25 @@ parseNewHaProxy localProxyInfo = do
 
     toUnixPath = S.unpack . fst . S.break (=='\x00')
 
-foreign import ccall unsafe "iostreams_ntohs" c_ntohs :: CUShort -> CUShort
-foreign import ccall unsafe "iostreams_ntohl" c_ntohl :: CUInt -> CUInt
 
+#if WORDS_BIGENDIAN
+ntohs :: Word16 -> Word16
+ntohs = id
+
+ntohl :: Word32 -> Word32
+ntohl = id
+#elif MIN_VERSION_base(4,7,0)
 ntohs :: Word16 -> Word16
-ntohs = fromIntegral . c_ntohs . fromIntegral
+ntohs = byteSwap16
 
 ntohl :: Word32 -> Word32
-ntohl = fromIntegral . c_ntohl . fromIntegral
+ntohl = byteSwap32
+#else
+-- uint16_t ntohs(uint16_t netshort);
+foreign import capi unsafe "arpa/inet.h ntohs" ntohs :: Word16 -> Word16
+-- uint32_t ntohl(uint32_t netlong);
+foreign import capi unsafe "arpa/inet.h ntohl" ntohl :: Word32 -> Word32
+#endif
 
 snarf32 :: Parser Word32
 snarf32 = do