diff --git a/ChangeLog.md b/ChangeLog.md
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+++ b/ChangeLog.md
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+# Changelog for type-sets
+
+## 0.1.0.0 --- 2019-08-05
+
+Initial release!
+
+## Unreleased changes
diff --git a/LICENSE b/LICENSE
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--- /dev/null
+++ b/LICENSE
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+Copyright Sandy Maguire (c) 2019
+
+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 Sandy Maguire 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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+# cmptype
+
+## Dedication
+
+> Comparison is an act of violence against the self.
+>
+> Iyanla Vanzant
+
+
+## Overview
+
+`cmptype` provides a magical type family that lets you compare types:
+
+```haskell
+type family CmpType (a :: k) (b :: k) :: Ordering
+```
+
+When you turn on the `-fplugin=Type.Compare.Plugin` flag, it will let you
+compare arbitrary types. Why would you want such a thing? Probably because you
+want to write a type-level container that isn't a fucking list!
+
+
+## Acknowledgments
+
+Big thanks to [Boris Rozinov][oofp] for the initial idea, and for making as much
+coffee as I could drink while I wrote it. Also thanks to [Christiaan
+Baaij][chistiaanb] and [Matt Pickering][mpickering] for their indispensable help
+convincing GHC to do the right thing here.
+
+[oofp]: https://github.com/oofp
+[chistiaanb]: https://christiaanb.github.io/
+[mpickering]: http://mpickering.github.io/
+
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/magic-tyfams.cabal b/magic-tyfams.cabal
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--- /dev/null
+++ b/magic-tyfams.cabal
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+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: d2d7b9baf0c8c55312fee132eb5e0fbb0487626c4739f5510005a60ed17a8cd4
+
+name:           magic-tyfams
+version:        0.1.0.0
+synopsis:       Write plugins for magic type families with ease
+description:    Please see the README on GitHub at <https://github.com/isovector/type-sets/tree/master/cmptype#readme>
+category:       Compiler Plugin
+homepage:       https://github.com/https://github.com/isovector/type-sets/tree/master/cmptype#readme
+bug-reports:    https://github.com/https://github.com/isovector/type-sets/tree/master/cmptype/issues
+author:         Sandy Maguire
+maintainer:     sandy@sandymaguire.me
+copyright:      2019 Sandy Maguire
+license:        BSD3
+license-file:   LICENSE
+build-type:     Simple
+extra-source-files:
+    README.md
+    ChangeLog.md
+
+source-repository head
+  type: git
+  location: https://github.com/https://github.com/isovector/type-sets/tree/master/cmptype
+
+library
+  exposed-modules:
+      Plugin.MagicTyFam
+  other-modules:
+      Paths_magic_tyfams
+  hs-source-dirs:
+      src
+  build-depends:
+      base >=4.7 && <5
+    , ghc >=8.6.3 && <8.8
+    , ghc-tcplugins-extra >=0.3 && <0.4
+    , syb >=0.7 && <0.8
+  default-language: Haskell2010
diff --git a/src/Plugin/MagicTyFam.hs b/src/Plugin/MagicTyFam.hs
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--- /dev/null
+++ b/src/Plugin/MagicTyFam.hs
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+{-# LANGUAGE BangPatterns  #-}
+{-# LANGUAGE LambdaCase    #-}
+{-# LANGUAGE TupleSections #-}
+{-# OPTIONS_GHC -Wall      #-}
+
+module Plugin.MagicTyFam
+  ( magicTyFamPlugin
+
+    -- * Semantics
+  , withStuckSemantics
+  , isTyFamFree
+
+    -- * Low level stuff
+  , solveWanteds
+  , loadTyCon
+
+    -- * Re-exports
+  , Plugin
+  , TyCon
+  , Type
+  ) where
+
+import Control.Monad (guard)
+import Data.Generics (everything, mkQ)
+import Data.Traversable (for)
+import GHC.TcPluginM.Extra (lookupModule, lookupName, evByFiat)
+import GhcPlugins
+import TcEvidence (EvTerm (..))
+import TcPluginM (TcPluginM, tcLookupTyCon, newGiven)
+import TcRnTypes
+import TcType (isTyFamFree)
+
+
+------------------------------------------------------------------------------
+-- | Get your hands on the type constructor for your type family.
+loadTyCon
+    :: String  -- ^ package
+    -> String  -- ^ module
+    -> String  -- ^ identifier
+    -> TcPluginM TyCon
+loadTyCon p m i = do
+  md <- lookupModule (mkModuleName m) $ fsLit p
+  nm <- lookupName md $ mkTcOcc i
+  tcLookupTyCon nm
+
+
+------------------------------------------------------------------------------
+-- | Generate a plugin that solves instances of the type family pointed at by
+-- the three strings, via the function.
+magicTyFamPlugin
+    :: String  -- ^ package
+    -> String  -- ^ module
+    -> String  -- ^ identifier
+    -> ([Type] -> Maybe Type)
+    -> Plugin
+magicTyFamPlugin p m i f = defaultPlugin
+  { tcPlugin = const $ Just $ TcPlugin
+      { tcPluginInit = loadTyCon p m i
+      , tcPluginSolve = \cmp_type _ _ w ->
+          TcPluginOk [] <$> solveWanteds f cmp_type w
+      , tcPluginStop = const $ pure ()
+      }
+  , pluginRecompile = const $ pure NoForceRecompile
+  }
+
+
+------------------------------------------------------------------------------
+-- | Ensure that your resulting type family preserves the stuckness property,
+-- namely that it is stuck if any of its children are stuck.
+--
+-- You can use 'isTyFamFree' instead of 'withStuckSemantics' if you want tigher
+-- control over when your magic type family should be stuck.
+withStuckSemantics :: ([Type] -> Maybe Type) -> [Type] -> Maybe Type
+withStuckSemantics f ts = do
+  guard $ all isTyFamFree ts
+  f ts
+
+
+------------------------------------------------------------------------------
+-- | @solveWanteds f tyfam cts@ finds all instaces of @tyfam@ inside the wanted
+-- constraints @cts@, and evaluates them via @f@. The result is a set of
+-- 'CNonCanonical' constraints, which should be emitted as the second parameter
+-- of 'TcPluginOk'.
+solveWanteds :: ([Type] -> Maybe Type) -> TyCon -> [Ct] -> TcPluginM [Ct]
+solveWanteds _ _ [] = pure []
+solveWanteds f cmp_type wanted = do
+  let rel = fmap (findRelevant f cmp_type . ctLoc <*> ctev_pred . cc_ev) wanted
+
+  gs <- for (concat rel) $ \(MagicTyFamResult loc t res) -> do
+    let EvExpr ev = evByFiat "magic-tyfams" t res
+    newGiven loc (mkPrimEqPred t res) ev
+
+  pure $ fmap CNonCanonical gs
+
+
+------------------------------------------------------------------------------
+-- | Locate and expand the use of any type families.
+findRelevant :: ([Type] -> Maybe Type) -> TyCon -> CtLoc -> Type -> [MagicTyFamResult]
+findRelevant f cmp_type loc = everything (++) $ mkQ [] findCmpType
+  where
+    findCmpType t =
+      case splitTyConApp_maybe t of
+        Just (tc, ts) | tc == cmp_type ->
+           maybe [] (pure . MagicTyFamResult loc t) $ f ts
+        _ -> []
+
+
+data MagicTyFamResult = MagicTyFamResult
+  { _mtfrLoc      :: CtLoc
+  , _mtfrOriginal :: Type
+  , _mtfrSolved   :: Type
+  }
+