diff --git a/CHANGELOG.md b/CHANGELOG.md
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--- /dev/null
+++ b/CHANGELOG.md
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+# Version 0.1
+
+* Initial release.
diff --git a/LICENSE.txt b/LICENSE.txt
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--- /dev/null
+++ b/LICENSE.txt
@@ -0,0 +1,30 @@
+Copyright (c) 2015, Renzo Carbonara
+
+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 Renzo Carbonara 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
@@ -0,0 +1,2 @@
+See the README file in the @exinst@ package for more general documentation:
+https://hackage.haskell.org/package/exinst#readme
diff --git a/Setup.hs b/Setup.hs
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--- /dev/null
+++ b/Setup.hs
@@ -0,0 +1,2 @@
+import Distribution.Simple
+main = defaultMain
diff --git a/exinst-hashable.cabal b/exinst-hashable.cabal
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--- /dev/null
+++ b/exinst-hashable.cabal
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+name:                exinst-hashable
+version:             0.1
+author:              Renzo Carbonara
+maintainer:          renzoλcarbonara.com.ar
+copyright:           Renzo Carbonara 2015
+license:             BSD3
+license-file:        LICENSE.txt
+extra-source-files:  README.md CHANGELOG.md
+category:            Data
+build-type:          Simple
+cabal-version:       >=1.18
+synopsis:            Derive instances for the `hashable` library for your existential types.
+homepage:            https://github.com/k0001/exinst
+bug-reports:         https://github.com/k0001/exinst/issues
+
+library
+  hs-source-dirs: src/lib
+  default-language: Haskell2010
+  exposed-modules:
+      Exinst.Instances.Hashable
+  build-depends:
+      base >=4.7 && <4.9
+    , hashable >=1.2 && <1.3
+    , constraints >=0.4 && <0.5
+    , exinst >=0.1 && <0.2
+    , singletons >=1.1 && <1.2
+  ghcjs-options: -Wall -O3
+  ghc-options: -Wall -O2
diff --git a/src/lib/Exinst/Instances/Hashable.hs b/src/lib/Exinst/Instances/Hashable.hs
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--- /dev/null
+++ b/src/lib/Exinst/Instances/Hashable.hs
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+{-# LANGUAGE DataKinds #-}
+{-# LANGUAGE PolyKinds #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE UndecidableInstances #-}
+
+{-# OPTIONS_GHC -fno-warn-orphans #-}
+
+-- | This module exports 'Hashable' instances for 'Some1', 'Some2', 'Some3' and
+-- 'Some4' from "Exinst.Singletons", provided situable 'Dict1', 'Dict2', 'Dict3'
+-- and 'Dict4' instances are available.
+--
+-- See the README file in the @exinst@ package for more general documentation:
+-- https://hackage.haskell.org/package/exinst#readme
+module Exinst.Instances.Hashable () where
+
+import           Data.Hashable (Hashable(hashWithSalt))
+import           Data.Constraint
+import           Data.Singletons
+import           Exinst.Singletons
+import           Prelude
+
+--------------------------------------------------------------------------------
+
+-- | Some salt we add to hashes calculated in this module.
+salt0 :: Int
+salt0 = 6700417
+
+--------------------------------------------------------------------------------
+
+instance forall (f1 :: k1 -> *)
+  . ( SingKind ('KProxy :: KProxy k1)
+    , Hashable (DemoteRep ('KProxy :: KProxy k1))
+    , Dict1 Hashable f1
+    ) => Hashable (Some1 f1)
+  where
+    {-# INLINABLE hashWithSalt #-}
+    hashWithSalt salt some1x = withSome1Sing some1x $ \sa1 (x :: f1 a1) ->
+       case dict1 sa1 :: Dict (Hashable (f1 a1)) of
+          Dict -> salt `hashWithSalt` salt0
+                       `hashWithSalt` fromSing sa1
+                       `hashWithSalt` x
+
+instance forall (f2 :: k2 -> k1 -> *)
+  . ( SingKind ('KProxy :: KProxy k2)
+    , SingKind ('KProxy :: KProxy k1)
+    , Hashable (DemoteRep ('KProxy :: KProxy k2))
+    , Hashable (DemoteRep ('KProxy :: KProxy k1))
+    , Dict2 Hashable f2
+    ) => Hashable (Some2 f2)
+  where
+    {-# INLINABLE hashWithSalt #-}
+    hashWithSalt salt some2x = withSome2Sing some2x $ \sa2 sa1 (x :: f2 a2 a1) ->
+       case dict2 sa2 sa1 :: Dict (Hashable (f2 a2 a1)) of
+          Dict -> salt `hashWithSalt` salt0
+                       `hashWithSalt` fromSing sa2
+                       `hashWithSalt` fromSing sa1
+                       `hashWithSalt` x
+
+instance forall (f3 :: k3 -> k2 -> k1 -> *)
+  . ( SingKind ('KProxy :: KProxy k3)
+    , SingKind ('KProxy :: KProxy k2)
+    , SingKind ('KProxy :: KProxy k1)
+    , Hashable (DemoteRep ('KProxy :: KProxy k3))
+    , Hashable (DemoteRep ('KProxy :: KProxy k2))
+    , Hashable (DemoteRep ('KProxy :: KProxy k1))
+    , Dict3 Hashable f3
+    ) => Hashable (Some3 f3)
+  where
+    {-# INLINABLE hashWithSalt #-}
+    hashWithSalt salt some3x = withSome3Sing some3x $ \sa3 sa2 sa1 (x :: f3 a3 a2 a1) ->
+       case dict3 sa3 sa2 sa1 :: Dict (Hashable (f3 a3 a2 a1)) of
+          Dict -> salt `hashWithSalt` salt0
+                       `hashWithSalt` fromSing sa3
+                       `hashWithSalt` fromSing sa2
+                       `hashWithSalt` fromSing sa1
+                       `hashWithSalt` x
+
+instance forall (f4 :: k4 -> k3 -> k2 -> k1 -> *)
+  . ( SingKind ('KProxy :: KProxy k4)
+    , SingKind ('KProxy :: KProxy k3)
+    , SingKind ('KProxy :: KProxy k2)
+    , SingKind ('KProxy :: KProxy k1)
+    , Hashable (DemoteRep ('KProxy :: KProxy k4))
+    , Hashable (DemoteRep ('KProxy :: KProxy k3))
+    , Hashable (DemoteRep ('KProxy :: KProxy k2))
+    , Hashable (DemoteRep ('KProxy :: KProxy k1))
+    , Dict4 Hashable f4
+    ) => Hashable (Some4 f4)
+  where
+    {-# INLINABLE hashWithSalt #-}
+    hashWithSalt salt some4x = withSome4Sing some4x $ \sa4 sa3 sa2 sa1 (x :: f4 a4 a3 a2 a1) ->
+       case dict4 sa4 sa3 sa2 sa1 :: Dict (Hashable (f4 a4 a3 a2 a1)) of
+          Dict -> salt `hashWithSalt` salt0
+                       `hashWithSalt` fromSing sa4
+                       `hashWithSalt` fromSing sa3
+                       `hashWithSalt` fromSing sa2
+                       `hashWithSalt` fromSing sa1
+                       `hashWithSalt` x