diff --git a/Crypto/Cipher/Blowfish/Box.hs b/Crypto/Cipher/Blowfish/Box.hs
index 060873e..65a6942 100644
--- a/Crypto/Cipher/Blowfish/Box.hs
+++ b/Crypto/Cipher/Blowfish/Box.hs
@@ -5,13 +5,7 @@
 -- Portability : Good
 module Crypto.Cipher.Blowfish.Box
     ( Pbox
-    , Sbox
-    , mkBox
-    , iPbox
-    , iSbox0
-    , iSbox1
-    , iSbox2
-    , iSbox3
+    , boxes
     ) where
 
 import Data.Bits
@@ -22,8 +16,6 @@ import qualified Data.Vector as V
 import qualified Data.ByteString as B
 
 type Pbox = Vector Word32
-type Sbox = Vector Word32
-
 
 mkBox :: [Char] -> Vector Word32
 mkBox = V.fromList . map decode32be . doChunks 4 id . B.pack . map (fromIntegral . ord)
@@ -42,17 +34,13 @@ decode32be s = id $!
     (fromIntegral (s `B.index` 2) `shiftL`  8) .|.
     (fromIntegral (s `B.index` 3) )
 
-iPbox :: Pbox
-iPbox = mkBox "\
+boxes :: Pbox
+boxes = mkBox "\
     \\x24\x3f\x6a\x88\x85\xa3\x08\xd3\x13\x19\x8a\x2e\x03\x70\x73\x44\
     \\xa4\x09\x38\x22\x29\x9f\x31\xd0\x08\x2e\xfa\x98\xec\x4e\x6c\x89\
     \\x45\x28\x21\xe6\x38\xd0\x13\x77\xbe\x54\x66\xcf\x34\xe9\x0c\x6c\
     \\xc0\xac\x29\xb7\xc9\x7c\x50\xdd\x3f\x84\xd5\xb5\xb5\x47\x09\x17\
     \\x92\x16\xd5\xd9\x89\x79\xfb\x1b\
-    \"
-
-iSbox0 :: Sbox
-iSbox0  = mkBox "\
     \\xd1\x31\x0b\xa6\x98\xdf\xb5\xac\x2f\xfd\x72\xdb\xd0\x1a\xdf\xb7\
     \\xb8\xe1\xaf\xed\x6a\x26\x7e\x96\xba\x7c\x90\x45\xf1\x2c\x7f\x99\
     \\x24\xa1\x99\x47\xb3\x91\x6c\xf7\x08\x01\xf2\xe2\x85\x8e\xfc\x16\
@@ -117,10 +105,6 @@ iSbox0  = mkBox "\
     \\x08\xba\x6f\xb5\x57\x1b\xe9\x1f\xf2\x96\xec\x6b\x2a\x0d\xd9\x15\
     \\xb6\x63\x65\x21\xe7\xb9\xf9\xb6\xff\x34\x05\x2e\xc5\x85\x56\x64\
     \\x53\xb0\x2d\x5d\xa9\x9f\x8f\xa1\x08\xba\x47\x99\x6e\x85\x07\x6a\
-    \"
-
-iSbox1 :: Sbox
-iSbox1  = mkBox "\
     \\x4b\x7a\x70\xe9\xb5\xb3\x29\x44\xdb\x75\x09\x2e\xc4\x19\x26\x23\
     \\xad\x6e\xa6\xb0\x49\xa7\xdf\x7d\x9c\xee\x60\xb8\x8f\xed\xb2\x66\
     \\xec\xaa\x8c\x71\x69\x9a\x17\xff\x56\x64\x52\x6c\xc2\xb1\x9e\xe1\
@@ -185,10 +169,6 @@ iSbox1  = mkBox "\
     \\xdb\x73\xdb\xd3\x10\x55\x88\xcd\x67\x5f\xda\x79\xe3\x67\x43\x40\
     \\xc5\xc4\x34\x65\x71\x3e\x38\xd8\x3d\x28\xf8\x9e\xf1\x6d\xff\x20\
     \\x15\x3e\x21\xe7\x8f\xb0\x3d\x4a\xe6\xe3\x9f\x2b\xdb\x83\xad\xf7\
-    \"
-
-iSbox2 :: Sbox
-iSbox2  = mkBox "\
     \\xe9\x3d\x5a\x68\x94\x81\x40\xf7\xf6\x4c\x26\x1c\x94\x69\x29\x34\
     \\x41\x15\x20\xf7\x76\x02\xd4\xf7\xbc\xf4\x6b\x2e\xd4\xa2\x00\x68\
     \\xd4\x08\x24\x71\x33\x20\xf4\x6a\x43\xb7\xd4\xb7\x50\x00\x61\xaf\
@@ -253,10 +233,6 @@ iSbox2  = mkBox "\
     \\x1e\x50\xef\x5e\xb1\x61\xe6\xf8\xa2\x85\x14\xd9\x6c\x51\x13\x3c\
     \\x6f\xd5\xc7\xe7\x56\xe1\x4e\xc4\x36\x2a\xbf\xce\xdd\xc6\xc8\x37\
     \\xd7\x9a\x32\x34\x92\x63\x82\x12\x67\x0e\xfa\x8e\x40\x60\x00\xe0\
-    \"
-
-iSbox3 :: Sbox
-iSbox3  = mkBox "\
     \\x3a\x39\xce\x37\xd3\xfa\xf5\xcf\xab\xc2\x77\x37\x5a\xc5\x2d\x1b\
     \\x5c\xb0\x67\x9e\x4f\xa3\x37\x42\xd3\x82\x27\x40\x99\xbc\x9b\xbe\
     \\xd5\x11\x8e\x9d\xbf\x0f\x73\x15\xd6\x2d\x1c\x7e\xc7\x00\xc4\x7b\
diff --git a/Crypto/Cipher/Blowfish/Primitive.hs b/Crypto/Cipher/Blowfish/Primitive.hs
index 861cc2d..9879760 100644
--- a/Crypto/Cipher/Blowfish/Primitive.hs
+++ b/Crypto/Cipher/Blowfish/Primitive.hs
@@ -18,6 +18,7 @@ module Crypto.Cipher.Blowfish.Primitive
     , decrypt
     ) where
 
+import Control.Monad (forM_)
 import Data.Vector (Vector, (!), (//))
 import qualified Data.Vector as V
 import qualified Data.Vector.Mutable as V (unsafeRead, unsafeWrite)
@@ -64,7 +65,7 @@ initBlowfish key
 keyFromByteString :: B.ByteString -> CryptoFailable Context
 keyFromByteString k
     | B.length k /= (18 * 4) = CryptoFailed CryptoError_KeySizeInvalid
-    | otherwise              = CryptoPassed . bfMakeKey . w8tow32 . B.unpack $ k
+    | otherwise              = CryptoPassed . makeKeySchedule . w8tow32 . B.unpack $ k
   where
     w8tow32 :: [Word8] -> [Word32]
     w8tow32 [] = []
@@ -95,13 +96,15 @@ coreCrypto (BF p s0 s1 s2 s3) input = doRound input 0
               d = s3 (fromIntegral $ t .&. 0xff)
            in fromIntegral (((a + b) `xor` c) + d) `shiftL` 32
 
-bfMakeKey :: [Word32] -> Context
-bfMakeKey k = procKey [mixedBox,iSbox0,iSbox1,iSbox2,iSbox3]
-  where mixedBox = V.fromList $ zipWith xor k (map (\i -> iPbox ! i) [0..17])
-
-procKey :: [Vector Word32] -> Context
-procKey initialContext =
-    let v = unsafeDoIO (V.unsafeThaw (V.concat initialContext) >>= prepare >>= V.unsafeFreeze)
+makeKeySchedule :: [Word32] -> Context
+makeKeySchedule key =
+    let v = unsafeDoIO $ do
+              mv <- V.thaw boxes
+              forM_ (zip key [0..17]) $ \(k, i) ->
+                  V.unsafeRead mv i >>= \pVal -> V.unsafeWrite mv i (k `xor` pVal)
+                  --mutableArrayWriteXor32 mv i k
+              prepare mv
+              V.unsafeFreeze mv
      in BF (V.slice 0 18 v !)
            (V.slice s0 256 v !)
            (V.slice s1 256 v !)
@@ -113,7 +116,7 @@ procKey initialContext =
         s2 = 530
         s3 = 786
 
-        prepare mctx = loop 0 0 >> return mctx
+        prepare mctx = loop 0 0
           where loop i input
                   | i == 1042   = return ()
                   | otherwise = do