diff --git a/LICENSE b/LICENSE
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--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,30 @@
+Copyright (c) 2015, Athan Clark
+
+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 Athan Clark 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/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/poly-arity.cabal b/poly-arity.cabal
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--- /dev/null
+++ b/poly-arity.cabal
@@ -0,0 +1,35 @@
+Name:                   poly-arity
+Version:                0.0.1
+Author:                 Athan Clark <athan.clark@gmail.com>
+Maintainer:             Athan Clark <athan.clark@gmail.com>
+License:                BSD3
+License-File:           LICENSE
+Synopsis:               Tools for working with functions of undetermined arity
+-- Description:
+Cabal-Version:          >= 1.10
+Build-Type:             Simple
+
+Library
+  Default-Language:     Haskell2010
+  HS-Source-Dirs:       src
+  GHC-Options:          -Wall
+  Exposed-Modules:      Data.Function.Poly
+  Build-Depends:        base >= 4 && < 5
+                      , constraints
+                      , HList
+
+Test-Suite spec
+  Type:                 exitcode-stdio-1.0
+  Default-Language:     Haskell2010
+  Hs-Source-Dirs:       src
+                      , test
+  Ghc-Options:          -Wall
+  Main-Is:              Spec.hs
+  Build-Depends:        base
+                      , hspec
+                      , QuickCheck
+                      , quickcheck-instances
+
+Source-Repository head
+  Type:                 git
+  Location:             https://github.com/athanclark/poly-arity.git
diff --git a/src/Data/Function/Poly.hs b/src/Data/Function/Poly.hs
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--- /dev/null
+++ b/src/Data/Function/Poly.hs
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+{-# LANGUAGE
+    TypeFamilies
+  , KindSignatures
+  , DataKinds
+  , ConstraintKinds
+  , TypeOperators
+  , MultiParamTypeClasses
+  , FunctionalDependencies
+  , PolyKinds
+  , FlexibleInstances
+  , UndecidableInstances
+  #-}
+
+module Data.Function.Poly where
+
+import Data.Constraint
+import Data.HList
+
+
+type family TypeListToArity (xs :: [*]) (r :: *) :: * where
+  TypeListToArity '[] r = r -- basis
+  TypeListToArity (x ': xs) r = x -> TypeListToArity xs r
+
+type family ExpectArity (xs :: [*]) (f :: *) :: Constraint where
+  ExpectArity '[] f = () -- basis
+  ExpectArity (x ': xs) (x -> remainder) = ExpectArity xs remainder
+
+type family Head (xs :: [k]) :: k where
+  Head (x ': xs) = x
+
+type family Tail (xs :: [k]) :: [k] where
+  Tail (x ': xs) = xs
+
+
+class ExpectArity xs f => ConsumeArity (xs :: [*]) (f :: *) result | xs f -> result where
+  appN :: f -> HList xs -> result
+
+instance ConsumeArity '[] r r where
+  appN r _ = r
+
+instance ( ConsumeArity xs f r
+         , ExpectArity (x ': xs) (x -> f) )=> ConsumeArity (x ': xs) (x -> f) r where
+  appN f (HCons x xs) = appN (f x) xs
diff --git a/test/Spec.hs b/test/Spec.hs
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--- /dev/null
+++ b/test/Spec.hs
@@ -0,0 +1,1 @@
+{-# OPTIONS_GHC -F -pgmF hspec-discover #-}