diff --git a/ChangeLog.md b/ChangeLog.md
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--- /dev/null
+++ b/ChangeLog.md
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+# Changelog for type-flip
+
+## Unreleased changes
diff --git a/LICENSE b/LICENSE
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--- /dev/null
+++ b/LICENSE
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+Copyright Author name here (c) 2020
+
+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 name of Author name here nor the names of other
+      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/README.md b/README.md
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--- /dev/null
+++ b/README.md
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+# type-flip
+Flip Foo a b = Foo b a
diff --git a/Setup.hs b/Setup.hs
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--- /dev/null
+++ b/Setup.hs
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+import Distribution.Simple
+main = defaultMain
diff --git a/src/Data/Type/Flip.hs b/src/Data/Type/Flip.hs
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--- /dev/null
+++ b/src/Data/Type/Flip.hs
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+{-# LANGUAGE FlexibleContexts #-}
+{-# OPTIONS_GHC -Wall -fno-warn-tabs #-}
+
+module Data.Type.Flip where
+
+newtype Flip t a b = Flip { unflip :: t b a } deriving Show
+
+infixl 4 <$%>, <*%>
+
+ffmap, (<$%>) :: Functor (Flip t c) => (a -> b) -> t a c -> t b c
+ffmap f = unflip . fmap f . Flip
+(<$%>) = ffmap
+
+fpure :: Applicative (Flip t b) => a -> t a b
+fpure = unflip . pure
+
+(<*%>) :: Applicative (Flip t c) => t (a -> b) c -> t a c -> t b c
+mf <*%> mx = unflip $ Flip mf <*> Flip mx
+
+infixl 1 >>=%
+
+(>>=%) :: Monad (Flip t c) => t a c -> (a -> t b c) -> t b c
+m >>=% f = unflip $ Flip m >>= Flip . f
+
+infixr 1 =<<%
+
+(=<<%) :: Monad (Flip t c) => (a -> t b c) -> t a c -> t b c
+(=<<%) = flip (>>=%)
+
+ftraverse :: (Applicative (Flip s c), Traversable t) => (a -> s b c) -> t a -> s (t b) c
+ftraverse f t = unflip $ traverse (Flip . f) t
+
+fsequence :: (Applicative (Flip s c), Traversable t) => t (s a c) -> s (t a) c
+fsequence tf = unflip . sequenceA $ Flip <$> tf
diff --git a/test/Spec.hs b/test/Spec.hs
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--- /dev/null
+++ b/test/Spec.hs
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+main :: IO ()
+main = putStrLn "Test suite not yet implemented"
diff --git a/type-flip.cabal b/type-flip.cabal
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--- /dev/null
+++ b/type-flip.cabal
@@ -0,0 +1,51 @@
+cabal-version: 1.12
+
+-- This file has been generated from package.yaml by hpack version 0.35.2.
+--
+-- see: https://github.com/sol/hpack
+--
+-- hash: c0f44803f74add22aa0bb537e94694de4cc32d950abfbf2ad8d03fbe50e6fb75
+
+name:           type-flip
+version:        0.1.0.0
+description:    Please see the README on GitHub at <https://github.com/githubuser/type-flip#readme>
+category:       Control
+homepage:       https://github.com/YoshikuniJujo/type-flip#readme
+bug-reports:    https://github.com/YoshikuniJujo/type-flip/issues
+author:         Yoshikuni Jujo
+maintainer:     yoshikuni.jujo@gmail.com
+copyright:      2020 Yoshikuni Jujo
+license:        BSD3
+license-file:   LICENSE
+build-type:     Simple
+extra-source-files:
+    README.md
+    ChangeLog.md
+
+source-repository head
+  type: git
+  location: https://github.com/YoshikuniJujo/type-flip
+
+library
+  exposed-modules:
+      Data.Type.Flip
+  other-modules:
+      Paths_type_flip
+  hs-source-dirs:
+      src
+  build-depends:
+      base >=4.7 && <5
+  default-language: Haskell2010
+
+test-suite type-flip-test
+  type: exitcode-stdio-1.0
+  main-is: Spec.hs
+  other-modules:
+      Paths_type_flip
+  hs-source-dirs:
+      test
+  ghc-options: -threaded -rtsopts -with-rtsopts=-N
+  build-depends:
+      base >=4.7 && <5
+    , type-flip
+  default-language: Haskell2010