diff --git a/LICENSE b/LICENSE
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--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,27 @@
+Copyright (c) 2011, Mikhail Vorozhtsov
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without 
+modification, are permitted provided that the following conditions are met:
+
+- Redistributions of source code must retain the above copyright notice, 
+  this list of conditions and the following disclaimer.
+- 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 names of the copyright owners nor the names of the 
+  contributors may be used to endorse or promote products derived 
+  from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
diff --git a/Setup.hs b/Setup.hs
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+++ b/Setup.hs
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+import Distribution.Simple
+main = defaultMain
diff --git a/data-endian.cabal b/data-endian.cabal
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--- /dev/null
+++ b/data-endian.cabal
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+Name: data-endian
+Version: 0.0.1
+Category: Data
+Stability: experimental
+Synopsis: Endian-sensitive data
+Description:
+  This package provides helpers for converting endian-sensitive data.
+
+Homepage: https://github.com/mvv/data-endian
+Bug-Reports: https://github.com/mvv/data-endian/issues
+
+Author: Mikhail Vorozhtsov <mikhail.vorozhtsov@gmail.com>
+Maintainer: Mikhail Vorozhtsov <mikhail.vorozhtsov@gmail.com>
+Copyright: 2011 Mikhail Vorozhtsov <mikhail.vorozhtsov@gmail.com>
+License: BSD3
+License-File: LICENSE
+
+Cabal-Version: >= 1.6.0
+Build-Type: Simple
+
+Source-Repository head
+  Type: git
+  Location: https://github.com/mvv/data-endian.git
+
+Library
+  Build-Depends: base < 5
+  Hs-Source-Dirs: src
+  GHC-Options: -Wall
+  Exposed-Modules:
+    Data.Endian
+
diff --git a/src/Data/Endian.hs b/src/Data/Endian.hs
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+++ b/src/Data/Endian.hs
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+{-# LANGUAGE UnicodeSyntax #-}
+{-# LANGUAGE CPP #-}
+
+module Data.Endian (
+    EndianSensitive(..),
+    toBigEndian,
+    fromBigEndian,
+    toLittleEndian,
+    fromLittleEndian
+  ) where
+
+import Data.Int
+import Data.Word
+import Data.Bits
+import Foreign.C.Types
+import Foreign.Ptr (IntPtr, WordPtr)
+import System.Posix.Types (CSsize)
+
+#include <HsBaseConfig.h>
+
+-- | Raw, endian-sensitive data
+class EndianSensitive α where
+  -- | Change the endianness of the argument
+  swapEndian ∷ α → α
+
+-- | Convert from the native format to big-endian
+toBigEndian      ∷ EndianSensitive α ⇒ α → α
+-- | Convert from big-endian to the native format
+fromBigEndian    ∷ EndianSensitive α ⇒ α → α
+-- | Convert from the native format to little-endian
+toLittleEndian   ∷ EndianSensitive α ⇒ α → α
+-- | Convert from little-endian to the native format
+fromLittleEndian ∷ EndianSensitive α ⇒ α → α
+
+#ifdef WORDS_BIGENDIAN
+toBigEndian      = id
+toLittleEndian   = swapEndian
+#else
+toBigEndian      = swapEndian
+toLittleEndian   = id
+#endif
+
+fromBigEndian    = toBigEndian
+fromLittleEndian = toLittleEndian
+
+{-# INLINE toBigEndian #-}
+{-# INLINE fromBigEndian #-}
+{-# INLINE toLittleEndian #-}
+{-# INLINE fromLittleEndian #-}
+
+instance EndianSensitive α ⇒ EndianSensitive [α] where
+  swapEndian = map swapEndian
+
+instance EndianSensitive Word16 where
+  swapEndian = (`rotateR` 8)
+  {-# INLINE swapEndian #-}
+
+instance EndianSensitive Word32 where
+  swapEndian x  =  (x                  `shiftR` 24)
+               .|. ((x .&. 0x00FF0000) `shiftR` 8)
+               .|. ((x .&. 0x0000FF00) `shiftL` 8)
+               .|. (x                  `shiftL` 24)
+  {-# INLINE swapEndian #-}
+
+instance EndianSensitive Word64 where
+  swapEndian x
+#if WORD_SIZE_IN_BITS == 32
+    =  fromIntegral (swapEndian hi)
+   .|. (fromIntegral (swapEndian lo) `shiftL` 32)
+      where lo, hi ∷ Word32
+            lo = fromIntegral x
+            hi = fromIntegral (x `shiftR` 32)
+#else
+    =  (x                          `shiftR` 56)
+   .|. ((x .&. 0x00FF000000000000) `shiftR` 40)
+   .|. ((x .&. 0x0000FF0000000000) `shiftR` 24)
+   .|. ((x .&. 0x000000FF00000000) `shiftR` 8)
+   .|. ((x .&. 0x00000000FF000000) `shiftL` 8)
+   .|. ((x .&. 0x0000000000FF0000) `shiftL` 24)
+   .|. ((x .&. 0x000000000000FF00) `shiftL` 40)
+   .|. (x                          `shiftL` 56)
+#endif
+  {-# INLINE swapEndian #-}
+
+instance EndianSensitive Int16 where
+  swapEndian = (`rotateR` 8)
+  {-# INLINE swapEndian #-}
+
+instance EndianSensitive Int32 where
+  swapEndian = fromIntegral . (swapEndian ∷ Word32 → Word32) . fromIntegral
+  {-# INLINE swapEndian #-}
+
+instance EndianSensitive Int64 where
+  swapEndian = fromIntegral . (swapEndian ∷ Word64 → Word64) . fromIntegral
+  {-# INLINE swapEndian #-}
+
+instance EndianSensitive CShort where
+  swapEndian = fromIntegral
+             . (swapEndian ∷ HTYPE_SHORT → HTYPE_SHORT)
+             . fromIntegral
+  {-# INLINE swapEndian #-}
+
+instance EndianSensitive CUShort where
+  swapEndian = fromIntegral
+             . (swapEndian ∷ HTYPE_UNSIGNED_SHORT → HTYPE_UNSIGNED_SHORT)
+             . fromIntegral
+  {-# INLINE swapEndian #-}
+
+instance EndianSensitive CInt where
+  swapEndian = fromIntegral
+             . (swapEndian ∷ HTYPE_INT → HTYPE_INT)
+             . fromIntegral
+  {-# INLINE swapEndian #-}
+
+instance EndianSensitive CUInt where
+  swapEndian = fromIntegral
+             . (swapEndian ∷ HTYPE_UNSIGNED_INT → HTYPE_UNSIGNED_INT)
+             . fromIntegral
+  {-# INLINE swapEndian #-}
+
+instance EndianSensitive CLong where
+  swapEndian = fromIntegral
+             . (swapEndian ∷ HTYPE_LONG → HTYPE_LONG)
+             . fromIntegral
+  {-# INLINE swapEndian #-}
+
+instance EndianSensitive CULong where
+  swapEndian = fromIntegral
+             . (swapEndian ∷ HTYPE_UNSIGNED_LONG → HTYPE_UNSIGNED_LONG)
+             . fromIntegral
+  {-# INLINE swapEndian #-}
+
+#ifdef HAVE_LONG_LONG
+instance EndianSensitive CLLong where
+  swapEndian = fromIntegral
+             . (swapEndian ∷ HTYPE_LONG_LONG → HTYPE_LONG_LONG)
+             . fromIntegral
+  {-# INLINE swapEndian #-}
+
+instance EndianSensitive CULLong where
+  swapEndian = fromIntegral
+             . (swapEndian ∷ HTYPE_UNSIGNED_LONG_LONG
+                           → HTYPE_UNSIGNED_LONG_LONG)
+             . fromIntegral
+  {-# INLINE swapEndian #-}
+#endif
+
+instance EndianSensitive CSize where
+  swapEndian = fromIntegral
+             . (swapEndian ∷ HTYPE_SIZE_T → HTYPE_SIZE_T)
+             . fromIntegral
+  {-# INLINE swapEndian #-}
+
+instance EndianSensitive CSsize where
+  swapEndian = fromIntegral
+             . (swapEndian ∷ HTYPE_SSIZE_T → HTYPE_SSIZE_T)
+             . fromIntegral
+  {-# INLINE swapEndian #-}
+
+instance EndianSensitive CUIntPtr where
+  swapEndian = fromIntegral
+             . (swapEndian ∷ HTYPE_UINTPTR_T → HTYPE_UINTPTR_T)
+             . fromIntegral
+  {-# INLINE swapEndian #-}
+
+instance EndianSensitive CIntPtr where
+  swapEndian = fromIntegral
+             . (swapEndian ∷ HTYPE_INTPTR_T → HTYPE_INTPTR_T)
+             . fromIntegral
+  {-# INLINE swapEndian #-}
+
+instance EndianSensitive CPtrdiff where
+  swapEndian = fromIntegral
+             . (swapEndian ∷ HTYPE_PTRDIFF_T → HTYPE_PTRDIFF_T)
+             . fromIntegral
+  {-# INLINE swapEndian #-}
+
+instance EndianSensitive CUIntMax where
+  swapEndian = fromIntegral
+             . (swapEndian ∷ HTYPE_UINTMAX_T → HTYPE_UINTMAX_T)
+             . fromIntegral
+  {-# INLINE swapEndian #-}
+
+instance EndianSensitive CIntMax where
+  swapEndian = fromIntegral
+             . (swapEndian ∷ HTYPE_INTMAX_T → HTYPE_INTMAX_T)
+             . fromIntegral
+  {-# INLINE swapEndian #-}
+
+instance EndianSensitive WordPtr where
+  swapEndian = fromIntegral
+             . (swapEndian ∷ HTYPE_UINTPTR_T → HTYPE_UINTPTR_T)
+             . fromIntegral
+  {-# INLINE swapEndian #-}
+
+instance EndianSensitive IntPtr where
+  swapEndian = fromIntegral
+             . (swapEndian ∷ HTYPE_INTPTR_T → HTYPE_INTPTR_T)
+             . fromIntegral
+  {-# INLINE swapEndian #-}
+
+#ifdef HTYPE_WCHAR_T
+instance EndianSensitive CWchar where
+  swapEndian = fromIntegral
+             . (swapEndian ∷ HTYPE_WCHAR_T → HTYPE_WCHAR_T)
+             . fromIntegral
+  {-# INLINE swapEndian #-}
+#endif
+
+#ifdef HTYPE_WINT_T
+instance EndianSensitive CWint where
+  swapEndian = fromIntegral
+             . (swapEndian ∷ HTYPE_WINT_T → HTYPE_WINT_T)
+             . fromIntegral
+  {-# INLINE swapEndian #-}
+#endif
+