diff --git a/LICENSE b/LICENSE
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--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,29 @@
+BSD 3-Clause License
+
+Copyright (c) 2017, Tim McGilchrist
+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 the copyright holder nor the names of its
+  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 HOLDER 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/src/Control/Monad/Trans/Either.hs b/src/Control/Monad/Trans/Either.hs
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--- /dev/null
+++ b/src/Control/Monad/Trans/Either.hs
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+{-# LANGUAGE NoImplicitPrelude #-}
+{-# LANGUAGE PatternSynonyms #-}
+{-# LANGUAGE RankNTypes #-}
+-----------------------------------------------------------------------------
+-- |
+-- Module      :  Control.Monad.Trans.Either
+-- Copyright   :  (C) 2017 Tim McGilchrist
+-- License     :  BSD-style (see the file LICENSE)
+--
+-- Maintainer  :  timmcgil@gmail.com
+-- Stability   :  experimental
+-- Portability :  portable
+--
+-- This monad transformer extends "Control.Monad.Trans.Except" with a more
+-- familar "Either" naming.
+-----------------------------------------------------------------------------
+module Control.Monad.Trans.Either (
+  -- * Control.Monad.Trans.Either
+    EitherT
+  , newEitherT
+  , pattern EitherT
+  , runEitherT
+  , eitherT
+  , left
+  , right
+  , mapEitherT
+  , hoistEither
+  , bimapEitherT
+
+  -- * Extensions
+  , firstEitherT
+  , secondEitherT
+  , hoistMaybe
+  , hoistEitherT
+  ) where
+
+import           Control.Monad (Monad(..), (=<<))
+import           Control.Monad.Trans.Except (ExceptT(..))
+
+import           Data.Maybe (Maybe, maybe)
+import           Data.Either (Either(..), either)
+import           Data.Function ((.), id)
+import           Data.Functor (Functor(..))
+
+------------------------------------------------------------------------
+-- Control.Monad.Trans.Either
+
+-- | Type alias for "ExceptT"
+--
+type EitherT = ExceptT
+
+pattern EitherT :: m (Either x a) -> ExceptT x m a
+pattern EitherT m = ExceptT m
+
+-- | Extractor for computations in the either monad.
+-- (The inverse of 'newEitherT').
+runEitherT :: EitherT x m a -> m (Either x a)
+runEitherT (ExceptT m) = m
+{-# INLINE runEitherT #-}
+
+-- | Constructor for computations in the either monad.
+-- (The inverse of 'runEitherT').
+newEitherT :: m (Either x a) -> EitherT x m a
+newEitherT =
+  ExceptT
+{-# INLINE newEitherT #-}
+
+eitherT :: Monad m => (x -> m b) -> (a -> m b) -> EitherT x m a -> m b
+eitherT f g m =
+  either f g =<< runEitherT m
+{-# INLINE eitherT #-}
+
+-- | Constructor for left computations.
+left :: Monad m => x -> EitherT x m a
+left =
+  EitherT . return . Left
+{-# INLINE left #-}
+
+-- | Constructor for right computations.
+right :: Monad m => a -> EitherT x m a
+right =
+  return
+{-# INLINE right #-}
+
+-- |
+mapEitherT :: (m (Either x a) -> n (Either y b)) -> EitherT x m a -> EitherT y n b
+mapEitherT f =
+  EitherT . f . runEitherT
+{-# INLINE mapEitherT #-}
+
+-- | Hoist an "Either" into an "EitherT m"
+hoistEither :: Monad m => Either x a -> EitherT x m a
+hoistEither =
+  EitherT . return
+{-# INLINE hoistEither #-}
+
+-- | Map the unwrapped computation using the given function.
+bimapEitherT :: Functor m => (x -> y) -> (a -> b) -> EitherT x m a -> EitherT y m b
+bimapEitherT f g =
+  let
+    h (Left  e) = Left  (f e)
+    h (Right a) = Right (g a)
+  in
+    mapEitherT (fmap h)
+{-# INLINE bimapEitherT #-}
+
+-- | Map the 'Left' unwrapped computation using the given function.
+firstEitherT :: Functor m => (x -> y) -> EitherT x m a -> EitherT y m a
+firstEitherT f =
+  bimapEitherT f id
+{-# INLINE firstEitherT #-}
+
+-- | Map the 'Right' unwrapped computation using the given function.
+secondEitherT :: Functor m => (a -> b) -> EitherT x m a -> EitherT x m b
+secondEitherT =
+  bimapEitherT id
+{-# INLINE secondEitherT #-}
+
+-- | Hoist a 'Maybe a' into a 'Right a'
+hoistMaybe :: Monad m => x -> Maybe a -> EitherT x m a
+hoistMaybe x =
+  maybe (left x) return
+{-# INLINE hoistMaybe #-}
+
+-- | Hoist
+hoistEitherT :: (forall b. m b -> n b) -> EitherT x m a -> EitherT x n a
+hoistEitherT f =
+  EitherT . f . runEitherT
+{-# INLINE hoistEitherT #-}
diff --git a/transformers-either.cabal b/transformers-either.cabal
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+name:                  transformers-either
+version:               0.0.1
+license:               BSD3
+license-file:          LICENSE
+author:                Tim McGilchrist <timmcgil@gmail.com>
+maintainer:            Tim McGilchrist <timmcgil@gmail.com>
+copyright:             (c) 2017 Tim McGilchrist
+synopsis:              An Either monad transformer
+category:              System
+cabal-version:         >= 1.8
+build-type:            Simple
+description:
+            Drop in alternative to ExceptT.
+
+            Uses a pattern synonym to maintain compatibility with the old EitherT types
+            but is actually ExceptT under the covers.
+       
+source-repository head
+  type: git
+  location: https://github.com/tmcgilchrist/transformers-either.git
+                
+library
+  build-depends:
+                       base                            >= 3          && < 5
+                     , transformers                    >= 0.4        && < 0.6
+
+  ghc-options:
+                       -Wall
+
+  hs-source-dirs:
+                       src
+
+  exposed-modules:
+                       Control.Monad.Trans.Either