diff --git a/CoreDump.cabal b/CoreDump.cabal
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--- /dev/null
+++ b/CoreDump.cabal
@@ -0,0 +1,30 @@
+name:                CoreDump
+version:             0.1.0.0
+
+synopsis:
+  A GHC plugin for printing GHC's internal Core data structures.
+
+description:         See README file.
+
+license:             BSD3
+license-file:        LICENSE
+author:              Ömer Sinan Ağacan
+maintainer:          omeragacan@gmail.com
+category:            GHC
+build-type:          Simple
+cabal-version:       >=1.10
+
+source-repository head
+  type:                git
+  location:            git://github.com/osa1/CoreDump.git
+
+library
+  exposed-modules:     CoreDump
+  other-modules:       CoreDump.Show
+  build-depends:
+    base >= 4.8 && < 4.9,
+    ghc  >= 7.10 && < 8,
+    haskell-src-exts
+  hs-source-dirs:      src
+  default-language:    Haskell2010
+  ghc-options:         -Wall
diff --git a/LICENSE b/LICENSE
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--- /dev/null
+++ b/LICENSE
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+Copyright (c) 2015, Omer Sinan Agacan
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without modification,
+are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer.
+
+2. 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.
+
+3. 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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--- /dev/null
+++ b/Setup.hs
@@ -0,0 +1,2 @@
+import Distribution.Simple
+main = defaultMain
diff --git a/src/CoreDump.hs b/src/CoreDump.hs
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--- /dev/null
+++ b/src/CoreDump.hs
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+module CoreDump (plugin) where
+
+import GhcPlugins
+
+import Data.IORef (writeIORef)
+import Data.List (intersperse)
+
+-- For pretty-printing
+import Language.Haskell.Exts.Parser
+import Language.Haskell.Exts.Pretty
+
+import CoreDump.Show
+
+plugin :: Plugin
+plugin = defaultPlugin{installCoreToDos = installPlugin}
+  where
+    installPlugin :: [CommandLineOption] -> [CoreToDo] -> CoreM [CoreToDo]
+    installPlugin opts todos = do
+      getDynFlags >>= liftIO . writeIORef dynFlags_ref
+      -- trace ("opts: " ++ show opts) (return ())
+      return $ concat
+        [ if before then [CoreDoPluginPass "CoreDump - before" pluginPass] else []
+        , todos
+        , if after then [CoreDoPluginPass "CoreDump - after" pluginPass] else []
+        ]
+      where
+        both   = "both"   `elem` opts
+        before = "before" `elem` opts || both
+        after  = "after"  `elem` opts || both
+
+pluginPass :: ModGuts -> CoreM ModGuts
+pluginPass guts@ModGuts{ mg_binds = binds } = do
+    liftIO $ mapM_ putStrLn $ intersperse "" $ map showPretty binds
+    return guts
+
+showPretty :: Show a => a -> String
+showPretty a =
+    case parseExp s of
+      ParseOk x          -> prettyPrint x
+      -- ParseFailed loc reason ->
+      --   trace ("parse failed: " ++ show (loc, reason)) s
+      ParseFailed{}      -> s
+  where
+    s = show a
diff --git a/src/CoreDump/Show.hs b/src/CoreDump/Show.hs
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--- /dev/null
+++ b/src/CoreDump/Show.hs
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+{-# LANGUAGE FlexibleInstances, StandaloneDeriving, TypeSynonymInstances #-}
+
+{-# OPTIONS_GHC -fno-warn-orphans #-}
+
+-- | We define lots of orphan Show instances here, for debugging and learning
+-- purposes.
+--
+-- Most of the time while trying to figure out when a constructor is used or how
+-- is a term compiled, it's easiest to just create an example and run the plugin
+-- on it.
+--
+-- Without Show instances though, we can't easily inspect compiled outputs.
+-- Outputable generated strings hide lots of details(especially constructors),
+-- but we still export a `showOutputable` here, for similar reasons.
+--
+module CoreDump.Show where
+
+-- import Control.Monad.IO.Class
+import Data.IORef
+import System.IO.Unsafe (unsafePerformIO)
+
+import Class
+import CostCentre
+import Demand
+import ForeignCall
+import GhcPlugins
+import IdInfo
+import PrimOp
+import TypeRep
+
+import Prelude
+
+--------------------------------------------------------------------------------
+
+{-# NOINLINE dynFlags_ref #-}
+dynFlags_ref :: IORef DynFlags
+dynFlags_ref = unsafePerformIO (newIORef undefined)
+
+{-# NOINLINE dynFlags #-}
+dynFlags :: DynFlags
+dynFlags = unsafePerformIO (readIORef dynFlags_ref)
+
+-- initDynFlags :: (HasDynFlags m, MonadIO m) => m ()
+-- initDynFlags = getDynFlags >>= liftIO .writeIORef dynFlags
+
+showOutputable :: Outputable a => a -> String
+showOutputable = showSDoc dynFlags . ppr
+
+--------------------------------------------------------------------------------
+-- * Orphan Show instances
+
+deriving instance Show a => Show (Expr a)
+deriving instance Show Type
+deriving instance Show Literal
+deriving instance Show a => Show (Tickish a)
+deriving instance Show a => Show (Bind a)
+deriving instance Show AltCon
+deriving instance Show TyLit
+deriving instance Show FunctionOrData
+deriving instance Show Module
+deriving instance Show CostCentre
+deriving instance Show Role
+deriving instance Show LeftOrRight
+deriving instance Show IsCafCC
+
+instance Show Class where
+  show _ = "Class"
+
+deriving instance Show IdDetails
+deriving instance Show PrimOp
+deriving instance Show ForeignCall
+deriving instance Show TickBoxOp
+deriving instance Show PrimOpVecCat
+deriving instance Show CCallSpec
+deriving instance Show CCallTarget
+deriving instance Show CCallConv
+deriving instance Show SpecInfo
+deriving instance Show OccInfo
+deriving instance Show InlinePragma
+deriving instance Show OneShotInfo
+deriving instance Show CafInfo
+deriving instance Show Unfolding
+deriving instance Show UnfoldingSource
+deriving instance Show UnfoldingGuidance
+deriving instance Show Activation
+deriving instance Show CoreRule
+deriving instance Show StrictSig
+deriving instance Show DmdType
+
+instance Show RuleFun where
+  show _ = "RuleFun"
+
+instance Show (UniqFM a) where
+  show _ = "UniqFM"
+
+data SIdInfo
+  = IdInfo Arity SpecInfo Unfolding CafInfo
+           OneShotInfo InlinePragInfo OccInfo
+           StrictSig Demand ArityInfo
+  deriving (Show)
+
+instance Show IdInfo where
+  show info = show (IdInfo arityInfo_ specInfo_ unfoldingInfo_
+                           cafInfo_ oneShotInfo_ inlinePragInfo_
+                           occInfo_ strictnessInfo_ demandInfo_
+                           callArityInfo_)
+    where
+      arityInfo_ = arityInfo info
+      specInfo_  = specInfo info
+      unfoldingInfo_ = unfoldingInfo info
+      cafInfo_   = cafInfo info
+      oneShotInfo_ = oneShotInfo info
+      inlinePragInfo_ = inlinePragInfo info
+      occInfo_ = occInfo info
+      strictnessInfo_ = strictnessInfo info
+      demandInfo_ = demandInfo info
+      callArityInfo_ = callArityInfo info
+
+-- Unique's Show instance is not parseable by haskell-src-exts,
+-- disabling it for now
+data SId = Id Name {- Unique -} Type IdDetails IdInfo
+  deriving (Show)
+
+data STyVar = TyVar Name
+  deriving (Show)
+
+instance Show Var where
+    show v
+      | isId v    = show (Id name {- uniq_ -} ty details info)
+      | otherwise = show (TyVar name)
+      where
+        name = varName v
+        -- uniq_ = varUnique v
+        ty   = varType v
+
+        details = idDetails v
+        info    = idInfo v
+
+instance Show DataCon where
+    show = show . dataConName
+
+instance Show TyCon where
+    show = show . tyConName
+
+instance Show ModuleName where
+    show = show . moduleNameString
+
+instance Show PackageKey where
+    show = show . packageKeyString
+
+instance Show Name where
+    show = showOutputable . nameOccName
+
+-- deriving instance Show Name
+instance Show OccName where
+    show = showOutputable
+
+instance Show Coercion where
+    show _ = "Coercion"
+
+-- Instance for non-terms related stuff.
+
+deriving instance Show CoreToDo
+deriving instance Show SimplifierMode
+deriving instance Show CompilerPhase
+deriving instance Show FloatOutSwitches
+
+instance Show PluginPass where
+    show _ = "PluginPass"