diff --git a/README.md b/README.md
deleted file mode 100644
--- a/README.md
+++ /dev/null
@@ -1,19 +0,0 @@
-# string-transform
-
-[![Build Status](https://travis-ci.org/ncaq/string-transform.svg?branch=master)](https://travis-ci.org/ncaq/string-transform)
-![Hackage](https://img.shields.io/hackage/v/string-transform.svg)
-
-simple and easy haskell string transform wrapper.
-
-# provide function
-
-* `toString`
-* `toByteStringStrict`
-* `toByteStringLazy`
-* `toShortByteString`
-* `toTextStrict`
-* `toTextLazy`
-
-# note
-
-It wrapper expect that `ByteString` encode is utf-8.
diff --git a/src/Data/String/Transform.hs b/src/Data/String/Transform.hs
--- a/src/Data/String/Transform.hs
+++ b/src/Data/String/Transform.hs
@@ -13,127 +13,163 @@
 import qualified Data.Text.Lazy.Encoding   as TL
 
 class ToString a where
-    toString :: a -> String
+  toString :: a -> String
 
 instance ToString String where
-    toString = id
+  toString = id
+  {-# INLINE toString #-}
 
 instance ToString B.ByteString where
-    toString = BU.toString
+  toString = BU.toString
+  {-# INLINE toString #-}
 
 instance ToString BL.ByteString where
-    toString = BLU.toString
+  toString = BLU.toString
+  {-# INLINE toString #-}
 
 instance ToString BS.ShortByteString where
-    toString = toString . BS.fromShort
+  toString = toString . BS.fromShort
+  {-# INLINE toString #-}
 
 instance ToString T.Text where
-    toString = T.unpack
+  toString = T.unpack
+  {-# INLINE toString #-}
 
 instance ToString TL.Text where
-    toString = TL.unpack
+  toString = TL.unpack
+  {-# INLINE toString #-}
 
 class ToByteStringStrict a where
-    toByteStringStrict :: a -> B.ByteString
+  toByteStringStrict :: a -> B.ByteString
 
 instance ToByteStringStrict String where
-    toByteStringStrict = BU.fromString
+  toByteStringStrict = BU.fromString
+  {-# INLINE toByteStringStrict #-}
 
 instance ToByteStringStrict B.ByteString where
-    toByteStringStrict = id
+  toByteStringStrict = id
+  {-# INLINE toByteStringStrict #-}
 
 instance ToByteStringStrict BL.ByteString where
-    toByteStringStrict = BL.toStrict
+  toByteStringStrict = BL.toStrict
+  {-# INLINE toByteStringStrict #-}
 
 instance ToByteStringStrict BS.ShortByteString where
-    toByteStringStrict = BS.fromShort
+  toByteStringStrict = BS.fromShort
+  {-# INLINE toByteStringStrict #-}
 
 instance ToByteStringStrict T.Text where
-    toByteStringStrict = T.encodeUtf8
+  toByteStringStrict = T.encodeUtf8
+  {-# INLINE toByteStringStrict #-}
 
 instance ToByteStringStrict TL.Text where
-    toByteStringStrict = toByteStringStrict . TL.toStrict
+  toByteStringStrict = toByteStringStrict . TL.toStrict
+  {-# INLINE toByteStringStrict #-}
 
 class ToByteStringLazy a where
-    toByteStringLazy :: a -> BL.ByteString
+  toByteStringLazy :: a -> BL.ByteString
 
 instance ToByteStringLazy String where
-    toByteStringLazy = BLU.fromString
+  toByteStringLazy = BLU.fromString
+  {-# INLINE toByteStringLazy #-}
 
 instance ToByteStringLazy B.ByteString where
-    toByteStringLazy = BL.fromStrict
+  toByteStringLazy = BL.fromStrict
+  {-# INLINE toByteStringLazy #-}
 
 instance ToByteStringLazy BL.ByteString where
-    toByteStringLazy = id
+  toByteStringLazy = id
+  {-# INLINE toByteStringLazy #-}
 
 instance ToByteStringLazy BS.ShortByteString where
-    toByteStringLazy = toByteStringLazy . BS.fromShort
+  toByteStringLazy = toByteStringLazy . BS.fromShort
+  {-# INLINE toByteStringLazy #-}
 
 instance ToByteStringLazy T.Text where
-    toByteStringLazy = toByteStringLazy . T.encodeUtf8
+  toByteStringLazy = toByteStringLazy . T.encodeUtf8
+  {-# INLINE toByteStringLazy #-}
 
 instance ToByteStringLazy TL.Text where
-    toByteStringLazy = TL.encodeUtf8
+  toByteStringLazy = TL.encodeUtf8
+  {-# INLINE toByteStringLazy #-}
 
 class ToShortByteString a where
-    toShortByteString :: a -> BS.ShortByteString
+  toShortByteString :: a -> BS.ShortByteString
 
 instance ToShortByteString String where
-    toShortByteString = toShortByteString . BU.fromString
+  toShortByteString = toShortByteString . BU.fromString
+  {-# INLINE toShortByteString #-}
 
 instance ToShortByteString B.ByteString where
-    toShortByteString = BS.toShort
+  toShortByteString = BS.toShort
+  {-# INLINE toShortByteString #-}
 
 instance ToShortByteString BL.ByteString where
-    toShortByteString = toShortByteString . toByteStringStrict
+  toShortByteString = toShortByteString . toByteStringStrict
+  {-# INLINE toShortByteString #-}
 
 instance ToShortByteString BS.ShortByteString where
-    toShortByteString = id
+  toShortByteString = id
+  {-# INLINE toShortByteString #-}
 
 instance ToShortByteString T.Text where
-    toShortByteString = toShortByteString . toByteStringStrict
+  toShortByteString = toShortByteString . toByteStringStrict
+  {-# INLINE toShortByteString #-}
 
 instance ToShortByteString TL.Text where
-    toShortByteString = toShortByteString . toByteStringStrict
+  toShortByteString = toShortByteString . toByteStringStrict
+  {-# INLINE toShortByteString #-}
 
 class ToTextStrict a where
-    toTextStrict :: a -> T.Text
+  toTextStrict :: a -> T.Text
 
 instance ToTextStrict String where
-    toTextStrict = T.pack
+  toTextStrict = T.pack
+  {-# INLINE toTextStrict #-}
 
 instance ToTextStrict B.ByteString where
-    toTextStrict = T.decodeUtf8
+  toTextStrict = T.decodeUtf8
+  {-# INLINE toTextStrict #-}
 
 instance ToTextStrict BL.ByteString where
-    toTextStrict = toTextStrict . BL.toStrict
+  toTextStrict = toTextStrict . BL.toStrict
+  {-# INLINE toTextStrict #-}
 
 instance ToTextStrict BS.ShortByteString where
-    toTextStrict = toTextStrict . BS.fromShort
+  toTextStrict = toTextStrict . BS.fromShort
+  {-# INLINE toTextStrict #-}
 
 instance ToTextStrict T.Text where
-    toTextStrict = id
+  toTextStrict = id
+  {-# INLINE toTextStrict #-}
 
 instance ToTextStrict TL.Text where
-    toTextStrict = TL.toStrict
+  toTextStrict = TL.toStrict
+  {-# INLINE toTextStrict #-}
 
 class ToTextLazy a where
-    toTextLazy :: a -> TL.Text
+  toTextLazy :: a -> TL.Text
 
 instance ToTextLazy String where
-    toTextLazy = TL.pack
+  toTextLazy = TL.pack
+  {-# INLINE toTextLazy #-}
 
 instance ToTextLazy B.ByteString where
-    toTextLazy = toTextLazy . BL.fromStrict
+  toTextLazy = toTextLazy . BL.fromStrict
+  {-# INLINE toTextLazy #-}
 
 instance ToTextLazy BL.ByteString where
-    toTextLazy = TL.decodeUtf8
+  toTextLazy = TL.decodeUtf8
+  {-# INLINE toTextLazy #-}
 
 instance ToTextLazy BS.ShortByteString where
-    toTextLazy = toTextLazy . toByteStringLazy
+  toTextLazy = toTextLazy . toByteStringLazy
+  {-# INLINE toTextLazy #-}
 
 instance ToTextLazy T.Text where
-    toTextLazy = TL.fromStrict
+  toTextLazy = TL.fromStrict
+  {-# INLINE toTextLazy #-}
 
 instance ToTextLazy TL.Text where
-    toTextLazy = id
+  toTextLazy = id
+  {-# INLINE toTextLazy #-}
diff --git a/string-transform.cabal b/string-transform.cabal
--- a/string-transform.cabal
+++ b/string-transform.cabal
@@ -1,11 +1,13 @@
--- This file has been generated from package.yaml by hpack version 0.20.0.
+cabal-version: 1.12
+
+-- This file has been generated from package.yaml by hpack version 0.31.2.
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: 5a82efa09e7668f37427521f7a85c669e793d5cbbb964ee5703aa1e9f4e66924
+-- hash: 4c0ad1d9ab8cad57c5a30c4152e3b0e7b2af0289c1feee194896ce204636a566
 
 name:           string-transform
-version:        1.1.0
+version:        1.1.1
 synopsis:       simple and easy haskell string transform wrapper
 category:       Text
 homepage:       https://github.com/ncaq/string-transform#readme
@@ -16,11 +18,7 @@
 license:        MIT
 license-file:   LICENSE
 build-type:     Simple
-cabal-version:  >= 1.10
 
-extra-source-files:
-    README.md
-
 source-repository head
   type: git
   location: https://github.com/ncaq/string-transform
@@ -28,7 +26,7 @@
 library
   hs-source-dirs:
       src
-  ghc-options: -Wall
+  ghc-options: -Wall -Widentities -Wincomplete-record-updates -Wincomplete-uni-patterns -Wmissing-exported-signatures -Wmissing-home-modules -Wredundant-constraints -Wcompat
   build-depends:
       base >=4.7 && <5
     , bytestring
@@ -45,7 +43,7 @@
   main-is: Main.hs
   hs-source-dirs:
       test
-  ghc-options: -Wall
+  ghc-options: -Wall -Widentities -Wincomplete-record-updates -Wincomplete-uni-patterns -Wmissing-exported-signatures -Wmissing-home-modules -Wredundant-constraints -Wcompat
   build-depends:
       base >=4.7 && <5
     , bytestring
diff --git a/test/Main.hs b/test/Main.hs
--- a/test/Main.hs
+++ b/test/Main.hs
@@ -11,32 +11,32 @@
 main = defaultMain $ testGroup "all-tests" tests
 
 tests :: [TestTree]
-tests =
-    [ testGroup "SmallCheck" smallCheckTest
+tests
+  = [ testGroup "SmallCheck" smallCheckTest
     , testGroup "Unit tests" hunitTest
     ]
 
 smallCheckTest :: [TestTree]
-smallCheckTest =
-    [ testProperty "s == toString (toByteStringStrict s)"
-        (\(s :: String) -> s == toString (toByteStringStrict s))
+smallCheckTest
+  = [ testProperty "s == toString (toByteStringStrict s)"
+      (\(s :: String) -> s == toString (toByteStringStrict s))
     , testProperty "s == toString (toByteStringLazy s)"
-        (\(s :: String) -> s == toString (toByteStringLazy s))
+      (\(s :: String) -> s == toString (toByteStringLazy s))
     , testProperty "s == toString (toShortByteString s)"
-        (\(s :: String) -> s == toString (toShortByteString s))
+      (\(s :: String) -> s == toString (toShortByteString s))
     , testProperty "s == toString (toTextStrict s)"
-        (\(s :: String) -> s == toString (toTextStrict s))
+      (\(s :: String) -> s == toString (toTextStrict s))
     , testProperty "s == toString (toTextLazy s)"
-        (\(s :: String) -> s == toString (toTextLazy s))
+      (\(s :: String) -> s == toString (toTextLazy s))
     , testProperty "a == b ⇔ toByteStringStrict a == toByteStringStrict b"
-        (\(a :: String) (b :: String) ->
-             let p = a == b
-                 q = toByteStringStrict a == toByteStringStrict b
-             in p == q)
+      (\(a :: String) (b :: String) ->
+          let p = a == b
+              q = toByteStringStrict a == toByteStringStrict b
+          in p == q)
     ]
 
 hunitTest :: [TestTree]
-hunitTest =
-    [ testCase "toByteStringStrict 日本語" (toString (toByteStringStrict "日本語") @?= "日本語")
+hunitTest
+  = [ testCase "toByteStringStrict 日本語" (toString (toByteStringStrict "日本語") @?= "日本語")
     , testCase "toString Text" (toString (T.pack "foo") @?= "foo")
     ]