From 193f916bdb76a432736897652fcd2ceeb432c0a7 Mon Sep 17 00:00:00 2001
From: "L. S. Leary" <LSLeary@users.noreply.github.com>
Date: Sun, 10 Feb 2019 10:36:11 +1300
Subject: [PATCH 01/18] Repinned and refactored nix files such that nix can
 actually build grin.

---
 default.nix            | 18 ++++++++++
 grin/default.nix       | 41 ---------------------
 nix/free.nix           | 20 -----------
 nix/llvm-hs-pretty.nix | 20 -----------
 nix/llvm-hs-pure.nix   | 20 -----------
 nix/llvm-hs.nix        | 26 --------------
 nix/llvm.nix           | 11 ++++++
 nix/pkgs.nix           |  8 +++++
 shell.nix              | 82 +++++-------------------------------------
 9 files changed, 45 insertions(+), 201 deletions(-)
 create mode 100644 default.nix
 delete mode 100644 grin/default.nix
 delete mode 100644 nix/free.nix
 delete mode 100644 nix/llvm-hs-pretty.nix
 delete mode 100644 nix/llvm-hs-pure.nix
 delete mode 100644 nix/llvm-hs.nix
 create mode 100644 nix/llvm.nix
 create mode 100644 nix/pkgs.nix

diff --git a/default.nix b/default.nix
new file mode 100644
index 00000000..598d76e0
--- /dev/null
+++ b/default.nix
@@ -0,0 +1,18 @@
+{ pkgs ? import nix/pkgs.nix }:
+
+let
+  hlib = pkgs.haskell.lib;
+  hpkg = pkgs.haskell.packages.ghc844;
+in
+
+hpkg.developPackage {
+  root = ./grin;
+  overrides = self: super: {
+    Diff = hlib.dontCheck super.Diff;
+    llvm-hs = super.llvm-hs.override (oa: {
+      llvm-config = pkgs.llvm_7;
+    });
+  };
+  modifier = drv: hlib.addBuildTool drv (import nix/llvm.nix {});
+  returnShellEnv = false;
+}
diff --git a/grin/default.nix b/grin/default.nix
deleted file mode 100644
index a1d2558d..00000000
--- a/grin/default.nix
+++ /dev/null
@@ -1,41 +0,0 @@
-{ Diff, mkDerivation, ansi-wl-pprint, base, bimap, bytestring, comonad
-, containers, criterion, deepseq, directory, extra, filepath, free
-, functor-infix, generic-random, ghc, ghc-paths, haskeline, hspec
-, hspec-discover, llvm-hs, llvm-hs-pretty, llvm-hs-pure
-, logict, megaparsec, microlens, microlens-mtl, microlens-platform
-, microlens-th, monad-gen, mtl, neat-interpolation
-, optparse-applicative, pretty-show, pretty-simple, process
-, QuickCheck, quickcheck-instances, recursion-schemes, set-extra
-, stdenv, template-haskell, text, text-short
-, transformers, unix, vector
-}:
-mkDerivation {
-  pname = "grin";
-  version = "0.1.0.0";
-  src = ./.;
-  isLibrary = true;
-  isExecutable = true;
-  libraryHaskellDepends = [
-    Diff ansi-wl-pprint base bimap bytestring comonad containers deepseq
-    directory extra filepath free functor-infix generic-random ghc
-    hspec llvm-hs llvm-hs-pretty llvm-hs-pure logict megaparsec
-    microlens microlens-mtl microlens-platform microlens-th monad-gen
-    mtl neat-interpolation optparse-applicative pretty-show
-    pretty-simple process QuickCheck quickcheck-instances recursion-schemes
-    set-extra template-haskell text text-short transformers vector
-  ];
-  executableHaskellDepends = [
-    ansi-wl-pprint base containers directory filepath ghc ghc-paths
-    haskeline llvm-hs-pretty megaparsec microlens microlens-mtl
-    microlens-platform microlens-th mtl optparse-applicative
-    pretty-show pretty-simple process recursion-schemes text
-    transformers unix
-  ];
-  testHaskellDepends = [
-    base containers deepseq functor-infix hspec hspec-discover
-    QuickCheck vector
-  ];
-  benchmarkHaskellDepends = [ base criterion ];
-  homepage = "https://github.com/githubuser/grin#readme";
-  license = stdenv.lib.licenses.bsd3;
-}
diff --git a/nix/free.nix b/nix/free.nix
deleted file mode 100644
index 958978b6..00000000
--- a/nix/free.nix
+++ /dev/null
@@ -1,20 +0,0 @@
-{ mkDerivation, base, bifunctors, comonad, containers, distributive
-, exceptions, mtl, prelude-extras, profunctors, semigroupoids
-, semigroups, stdenv, template-haskell, transformers
-, transformers-compat
-}:
-mkDerivation {
-  pname = "free";
-  version = "4.12.4";
-  sha256 = "c9fe45aae387855626ecb5a0fea6afdb207143cb00af3b1f715d1032d2d08784";
-  revision = "2";
-  editedCabalFile = "0gmib9bmswrqhl47cp5b871v9f44v9yidzxpljkszy49y9qdf560";
-  libraryHaskellDepends = [
-    base bifunctors comonad containers distributive exceptions mtl
-    prelude-extras profunctors semigroupoids semigroups
-    template-haskell transformers transformers-compat
-  ];
-  homepage = "http://github.com/ekmett/free/";
-  description = "Monads for free";
-  license = stdenv.lib.licenses.bsd3;
-}
diff --git a/nix/llvm-hs-pretty.nix b/nix/llvm-hs-pretty.nix
deleted file mode 100644
index e412b501..00000000
--- a/nix/llvm-hs-pretty.nix
+++ /dev/null
@@ -1,20 +0,0 @@
-{ mkDerivation, array, base, bytestring, directory, filepath
-, llvm-hs, llvm-hs-pure, mtl, pretty-show, stdenv, tasty
-, tasty-golden, tasty-hspec, tasty-hunit, text, transformers
-, wl-pprint-text
-}:
-mkDerivation {
-  pname = "llvm-hs-pretty";
-  version = "0.2.0.0";
-  sha256 = "90ce478f6386f836e3b646186c4fe4d72598cc938d8fbb150718a1bbf4f4738c";
-  libraryHaskellDepends = [
-    array base bytestring llvm-hs-pure text wl-pprint-text
-  ];
-  testHaskellDepends = [
-    base directory filepath llvm-hs llvm-hs-pure mtl pretty-show tasty
-    tasty-golden tasty-hspec tasty-hunit text transformers
-  ];
-  homepage = "https://github.com/llvm-hs/llvm-hs-pretty";
-  description = "Pretty printer for LLVM IR";
-  license = stdenv.lib.licenses.mit;
-}
diff --git a/nix/llvm-hs-pure.nix b/nix/llvm-hs-pure.nix
deleted file mode 100644
index 7c52a0f9..00000000
--- a/nix/llvm-hs-pure.nix
+++ /dev/null
@@ -1,20 +0,0 @@
-{ mkDerivation, attoparsec, base, bytestring, containers, fail
-, hspec, mtl, stdenv, tasty, tasty-hunit, tasty-quickcheck
-, template-haskell, text, transformers, unordered-containers
-}:
-mkDerivation {
-  pname = "llvm-hs-pure";
-  version = "5.1.2";
-  sha256 = "c4d0993aacda72107e6d34865421f128b8c27b586b95a68e2a3e94700645d954";
-  libraryHaskellDepends = [
-    attoparsec base bytestring containers fail mtl template-haskell
-    transformers unordered-containers
-  ];
-  testHaskellDepends = [
-    base bytestring containers hspec mtl tasty tasty-hunit
-    tasty-quickcheck text transformers unordered-containers
-  ];
-  homepage = "http://github.com/llvm-hs/llvm-hs/";
-  description = "Pure Haskell LLVM functionality (no FFI)";
-  license = stdenv.lib.licenses.bsd3;
-}
diff --git a/nix/llvm-hs.nix b/nix/llvm-hs.nix
deleted file mode 100644
index edea0e0f..00000000
--- a/nix/llvm-hs.nix
+++ /dev/null
@@ -1,26 +0,0 @@
-{ mkDerivation, array, attoparsec, base, bytestring, Cabal
-, containers, exceptions, llvm-config, llvm-hs-pure, mtl
-, pretty-show, QuickCheck, stdenv, tasty, tasty-hunit
-, tasty-quickcheck, template-haskell, temporary, transformers
-, utf8-string
-}:
-mkDerivation {
-  pname = "llvm-hs";
-  version = "5.1.3";
-  sha256 = "ccdac4683f56135ba83ed0883231f686d1784e9bc7f072a34fcf041e0661976b";
-  revision = "1";
-  editedCabalFile = "0r8xgz6r2miw1l3az343jwz8f9jgzqywxnzl2xhanv05g3i462yh";
-  setupHaskellDepends = [ base Cabal containers ];
-  libraryHaskellDepends = [
-    array attoparsec base bytestring containers exceptions llvm-hs-pure
-    mtl template-haskell transformers utf8-string
-  ];
-  libraryToolDepends = [ llvm-config ];
-  testHaskellDepends = [
-    base bytestring containers llvm-hs-pure mtl pretty-show QuickCheck
-    tasty tasty-hunit tasty-quickcheck temporary transformers
-  ];
-  homepage = "http://github.com/llvm-hs/llvm-hs/";
-  description = "General purpose LLVM bindings";
-  license = stdenv.lib.licenses.bsd3;
-}
diff --git a/nix/llvm.nix b/nix/llvm.nix
new file mode 100644
index 00000000..a8c389cc
--- /dev/null
+++ b/nix/llvm.nix
@@ -0,0 +1,11 @@
+{ pkgs ? import ./pkgs.nix }:
+
+pkgs.runCommand
+  "llvm-7-links"
+  { buildInputs = [ pkgs.llvm_7 ]; }
+  ''
+    mkdir -p $out/bin
+    cd $out/bin
+    ln -s ${pkgs.llvm_7}/bin/llc llc-7
+    ln -s ${pkgs.llvm_7}/bin/opt opt-7
+  ''
diff --git a/nix/pkgs.nix b/nix/pkgs.nix
new file mode 100644
index 00000000..b9c74793
--- /dev/null
+++ b/nix/pkgs.nix
@@ -0,0 +1,8 @@
+let
+  pinned = (import <nixpkgs> {}).fetchFromGitHub {
+    owner  = "NixOS";
+    repo   = "nixpkgs-channels";
+    rev    = "ffc604e55790dbf575187738e1c3778231e8f5a9";
+    sha256 = "1kw37ab6abkrjn65zhh0jcnfb3bzk1p14d178sp8489kn9gxy12v";
+  };
+in import pinned {}
diff --git a/shell.nix b/shell.nix
index 256a363e..c10737f8 100644
--- a/shell.nix
+++ b/shell.nix
@@ -1,74 +1,8 @@
-{ fetchFromGitHub ? (import <nixpkgs> {}).fetchFromGitHub
-# peg nix packages to specific version
-, pkgs ?
-    import
-      ( fetchFromGitHub
-        {
-          owner = "NixOS";
-          repo = "nixpkgs-channels";
-          rev = "696c6bed4e8e2d9fd9b956dea7e5d49531e9d13f";
-          sha256 = "1v3yrpj542niyxp0h3kffsdjwlrkvj0mg4ljb85d142gyn3sdzd4";
-        }
-      ) {}
-}:
-let
-    # extract the Haskell dependencies of a package
-    extractHaskellDependencies = (hpkg:
-        with builtins;
-        let
-          isHaskellPkg = x: (isAttrs x) && (x ? pname) && (x ? version) && (x ? env);
-          packagesFromDrv = x:
-            let
-              inputs =
-                (x.buildInputs or []) ++
-                (x.nativeBuildInputs or []) ++
-                (x.propagatedBuildInputs or []) ++
-                (x.propagatedNativeBuildInputs or []);
-
-            in
-              (filter isHaskellPkg  inputs);
-          go1 = s: xs: foldl' go2 s xs;
-          go2 = s: x:
-            if s ? "${x.pname}"
-               then s
-               else go1 (s // {"${x.pname}" = x;}) (packagesFromDrv x);
-        in assert isAttrs hpkg; attrNames (go1 {} (packagesFromDrv hpkg)));
-
-        # Haskell custom overrides
-        haskellPackages = pkgs.haskell.packages.ghc822.override (old:
-        { overrides = self: super:
-            {
-              free = self.callPackage ./nix/free.nix {};
-              functor-infix = pkgs.haskell.lib.doJailbreak (super.functor-infix);
-              llvm-hs = self.callPackage ./nix/llvm-hs.nix {llvm-config = pkgs.llvm_5;};
-              llvm-hs-pure = self.callPackage ./nix/llvm-hs-pure.nix {};
-              llvm-hs-pretty = pkgs.haskell.lib.dontCheck (self.callPackage ./nix/llvm-hs-pretty.nix {});
-            };
-        });
-
-    # the grin package
-    grin = pkgs.haskellPackages.callPackage ./grin {};
-    # grin's dependencies
-    grinDeps = extractHaskellDependencies grin;
-    # use a GHC with all the Hakell dependencies and the documentation for them and a Hoogle server to search them
-    ghcWith = haskellPackages.ghcWithHoogle (hs: map (x: builtins.getAttr x hs) grinDeps);
-
-    llc5 = pkgs.runCommand "llc5"
-      {
-        buildInputs = [pkgs.llvm_5];
-      }
-      ''
-        mkdir -p $out/bin
-        cd $out/bin
-        ln -s ${pkgs.llvm_5}/bin/llc llc-5.0
-      '';
-in
-# environment setup with all the needed tools
-pkgs.runCommand "grin-shell"
-      {
-        shellHook = ''
-          eval $(egrep ^export ${ghcWith}/bin/ghc)
-         '';
-        buildInputs = [ghcWith llc5 pkgs.llvm_5 haskellPackages.cabal-install];
-      }
-      "touch $out"
+{ pkgs ? import nix/pkgs.nix }:
+
+let grin = import ./. { inherit pkgs; };
+in pkgs.haskell.packages.ghc844.shellFor {
+  withHoogle = true;
+  packages = p: [ grin ];
+  inherit (grin.env) nativeBuildInputs;
+}

From 64dffc82de03ac88aa538ac497235a847caf935a Mon Sep 17 00:00:00 2001
From: "L. S. Leary" <LSLeary@users.noreply.github.com>
Date: Sun, 10 Feb 2019 10:42:05 +1300
Subject: [PATCH 02/18] Migrate megaparsec from 6.5 to 7.

---
 grin/app/GrinCLI.hs            |  2 +-
 grin/grin.cabal                |  4 ++--
 grin/src/Grin/Parse.hs         |  2 +-
 grin/src/Grin/Parse/AST.hs     | 10 +++++-----
 grin/src/Grin/Parse/Basic.hs   |  8 ++++----
 grin/src/Grin/Parse/TypeEnv.hs |  6 +++---
 grin/src/Grin/TH.hs            |  2 +-
 grin/src/Pipeline/Eval.hs      |  2 +-
 8 files changed, 18 insertions(+), 18 deletions(-)

diff --git a/grin/app/GrinCLI.hs b/grin/app/GrinCLI.hs
index 31ee796c..967586f4 100644
--- a/grin/app/GrinCLI.hs
+++ b/grin/app/GrinCLI.hs
@@ -159,7 +159,7 @@ main = do
         ((,) Nothing . Nametable.restore) <$> Binary.decodeFile fname
       else do
         content <- Text.readFile fname
-        let (typeEnv, program') = either (error . M.parseErrorPretty' content) id $ parseGrinWithTypes fname content
+        let (typeEnv, program') = either (error . M.errorBundlePretty) id $ parseGrinWithTypes fname content
         pure $ (Just typeEnv, if noPrelude then program' else concatPrograms [primPrelude, program'])
     let opts     = defaultOpts { _poOutputDir = outputDir, _poFailOnLint = True, _poLogging = not quiet, _poSaveBinary = saveBinary }
     case steps of
diff --git a/grin/grin.cabal b/grin/grin.cabal
index 448c53dc..6544664c 100644
--- a/grin/grin.cabal
+++ b/grin/grin.cabal
@@ -124,7 +124,7 @@ library
     bimap,
     mtl,
     comonad,
-    megaparsec,
+    megaparsec ==7.0.*,
     pretty-show,
     vector,
     deepseq,
@@ -175,7 +175,7 @@ executable grin
                      , grin
                      , recursion-schemes
                      , ansi-wl-pprint
-                     , megaparsec
+                     , megaparsec ==7.0.*
                      , containers
                      , process
                      , pretty-show
diff --git a/grin/src/Grin/Parse.hs b/grin/src/Grin/Parse.hs
index a5c9fad5..d3dda555 100644
--- a/grin/src/Grin/Parse.hs
+++ b/grin/src/Grin/Parse.hs
@@ -14,5 +14,5 @@ import Grin.TypeEnvDefs
 import Grin.Parse.AST
 import Grin.Parse.TypeEnv
 
-parseGrinWithTypes :: String -> Text -> Either (ParseError Char Void) (TypeEnv, Exp)
+parseGrinWithTypes :: String -> Text -> Either (ParseErrorBundle Text Void) (TypeEnv, Exp)
 parseGrinWithTypes filename content = (,) <$> parseMarkedTypeEnv filename content <*> parseGrin filename content
diff --git a/grin/src/Grin/Parse/AST.hs b/grin/src/Grin/Parse/AST.hs
index 0c74d15c..23792cb6 100644
--- a/grin/src/Grin/Parse/AST.hs
+++ b/grin/src/Grin/Parse/AST.hs
@@ -95,7 +95,7 @@ literal = (try $ LFloat . realToFrac <$> signedFloat) <|>
           (try $ LInt64 . fromIntegral <$> signedInteger) <|>
           (try $ LBool <$> (True <$ kw "#True" <|> False <$ kw "#False")) <|>
           (try $ LString <$> lexeme (C.char '#' *> quotedString)) <|>
-          (try $ LChar <$> lexeme (C.string "#'" *> (escaped <|> anyChar) <* C.char '\''))
+          (try $ LChar <$> lexeme (C.string "#'" *> (escaped <|> anySingle) <* C.char '\''))
 
 satisfyM :: (a -> Bool) -> Parser a -> Parser a
 satisfyM pred parser = do
@@ -138,17 +138,17 @@ tyP =
 grinModule :: Parser Exp
 grinModule = Program <$> (concat <$> many (try externalBlock)) <*> many def <* sc <* eof
 
-parseGrin :: String -> Text -> Either (ParseError Char Void) Exp
+parseGrin :: String -> Text -> Either (ParseErrorBundle Text Void) Exp
 parseGrin filename content = runParser grinModule filename (withoutTypeAnnots content)
 
 parseProg :: Text -> Exp
-parseProg src = either (error . parseErrorPretty' src) id . parseGrin "" $ withoutTypeAnnots src
+parseProg src = either (error . errorBundlePretty) id . parseGrin "" $ withoutTypeAnnots src
 
 parseDef :: Text -> Exp
-parseDef src = either (error . parseErrorPretty' src) id . runParser def "" $ withoutTypeAnnots src
+parseDef src = either (error . errorBundlePretty) id . runParser def "" $ withoutTypeAnnots src
 
 parseExpr :: Text -> Exp
-parseExpr src = either (error . parseErrorPretty' src) id . runParser (expr pos1) "" $ withoutTypeAnnots src
+parseExpr src = either (error . errorBundlePretty) id . runParser (expr pos1) "" $ withoutTypeAnnots src
 
 
 withoutTypeAnnots :: Text -> Text
diff --git a/grin/src/Grin/Parse/Basic.hs b/grin/src/Grin/Parse/Basic.hs
index a6ccc280..2372df66 100644
--- a/grin/src/Grin/Parse/Basic.hs
+++ b/grin/src/Grin/Parse/Basic.hs
@@ -95,8 +95,8 @@ set p = Set.fromList <$> bracedList p
 set1 :: Ord a => Parser a -> Parser (Set a)
 set1 p = Set.fromList <$> bracedList p
 
-anySingle :: MonadParsec e s m => m (Token s)
-anySingle = satisfy (const True)
+-- anySingle :: MonadParsec e s m => m (Token s)
+-- anySingle = satisfy (const True)
 
 anySingleBut :: MonadParsec e s m => Token s -> m (Token s)
 anySingleBut t = satisfy (/= t)
@@ -108,7 +108,7 @@ escaped :: Parser Char
 escaped = string "\\\"" >> pure '"'
 
 quotedVar :: Parser Name
-quotedVar = packName <$ char '"' <*> someTill (escaped <|> anyChar) (char '"')
+quotedVar = packName <$ char '"' <*> someTill (escaped <|> anySingle) (char '"')
 
 escapedStringChar :: Parser Char
 escapedStringChar =
@@ -123,7 +123,7 @@ escapedStringChar =
   (string "\\v" >> pure '\v')
 
 quotedString :: Parser Text
-quotedString = fromString <$> (char '"' *> manyTill (escapedStringChar <|> anyChar) (char '"'))
+quotedString = fromString <$> (char '"' *> manyTill (escapedStringChar <|> anySingle) (char '"'))
 
 simpleVar :: Parser Name
 simpleVar = (\c s -> packName $ c : s) <$> oneOf allowedInitial <*> many (alphaNumChar <|> oneOf allowedSpecial)
diff --git a/grin/src/Grin/Parse/TypeEnv.hs b/grin/src/Grin/Parse/TypeEnv.hs
index e62ce831..eb134874 100644
--- a/grin/src/Grin/Parse/TypeEnv.hs
+++ b/grin/src/Grin/Parse/TypeEnv.hs
@@ -113,15 +113,15 @@ entriesToTypeEnv xs = flip execState emptyTypeEnv $ do
 
 -- parses a type environment (without code)
 parseTypeEnv :: Text -> TypeEnv
-parseTypeEnv src = either (error . parseErrorPretty' src) id
+parseTypeEnv src = either (error . errorBundlePretty) id
                  . runParser typeEnv ""
                  $ src
 
 -- parses type marked type annotations (even interleaved with code)
 parseMarkedTypeEnv' :: Text -> TypeEnv
-parseMarkedTypeEnv' src = either (error . parseErrorPretty' src) id $ parseMarkedTypeEnv "" src
+parseMarkedTypeEnv' src = either (error . errorBundlePretty) id $ parseMarkedTypeEnv "" src
 
-parseMarkedTypeEnv :: String -> Text -> Either (ParseError Char Void) TypeEnv
+parseMarkedTypeEnv :: String -> Text -> Either (ParseErrorBundle Text Void) TypeEnv
 parseMarkedTypeEnv filename src = runParser markedTypeEnv filename (withoutCodeLines src)
 
 withoutCodeLines :: Text -> Text
diff --git a/grin/src/Grin/TH.hs b/grin/src/Grin/TH.hs
index 8d44969c..eb493234 100644
--- a/grin/src/Grin/TH.hs
+++ b/grin/src/Grin/TH.hs
@@ -51,7 +51,7 @@ progConst = QuasiQuoter
   { quoteExp = \input -> do
       let src = T.pack $ normalizeQQInput input
       case P.parseGrin "" src of
-        Left  e -> fail $ parseErrorPretty' src e
+        Left  e -> fail (errorBundlePretty e)
         Right p -> liftDataWithText p
   , quotePat  = undefined
   , quoteType = undefined
diff --git a/grin/src/Pipeline/Eval.hs b/grin/src/Pipeline/Eval.hs
index b2e23b9d..58d94f85 100644
--- a/grin/src/Pipeline/Eval.hs
+++ b/grin/src/Pipeline/Eval.hs
@@ -29,7 +29,7 @@ eval' :: Reducer -> String -> IO RTVal
 eval' reducer fname = do
   content <- Text.readFile fname
   case parseGrin fname content of
-    Left err -> error $ parseErrorPretty' content err
+    Left err -> error (errorBundlePretty err)
     Right program ->
       case reducer of
         PureReducer -> Reducer.Pure.reduceFun program "grinMain"

From c0ceacc7667b8b3e10e8dbf09c515827fd0891b2 Mon Sep 17 00:00:00 2001
From: "L. S. Leary" <LSLeary@users.noreply.github.com>
Date: Sun, 10 Feb 2019 10:50:19 +1300
Subject: [PATCH 03/18] Migrate QuickCheck from 2.11 to 2.12.

---
 grin/grin.cabal                                               | 4 ++--
 grin/src/Test/Test.hs                                         | 2 +-
 grin/test/Transformations/Optimising/ConstantFoldingSpec.hs   | 4 ++--
 .../Transformations/Simplifying/CaseSimplificationSpec.hs     | 2 +-
 4 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/grin/grin.cabal b/grin/grin.cabal
index 6544664c..f12d103a 100644
--- a/grin/grin.cabal
+++ b/grin/grin.cabal
@@ -155,7 +155,7 @@ library
     hspec-core,
     extra,
     logict,
-    QuickCheck,
+    QuickCheck ==2.12.*,
     quickcheck-instances,
     neat-interpolation,
     template-haskell,
@@ -205,7 +205,7 @@ test-suite grin-test
                      , hspec
                      , hspec-core
                      , hspec-discover
-                     , QuickCheck
+                     , QuickCheck ==2.12.*
                      , deepseq
                      , vector
                      , text
diff --git a/grin/src/Test/Test.hs b/grin/src/Test/Test.hs
index bdbc368b..56b7d5e0 100644
--- a/grin/src/Test/Test.hs
+++ b/grin/src/Test/Test.hs
@@ -903,4 +903,4 @@ instance Solve G.Prog where
     _    -> mzero
 
 changed :: (Testable prop) => Exp -> Exp -> prop -> Property
-changed old new = cover (old /= new) 1 "Transformation has effect"
+changed old new = cover 1 (old /= new) "Transformation has effect"
diff --git a/grin/test/Transformations/Optimising/ConstantFoldingSpec.hs b/grin/test/Transformations/Optimising/ConstantFoldingSpec.hs
index 76ea5c30..7eb86438 100644
--- a/grin/test/Transformations/Optimising/ConstantFoldingSpec.hs
+++ b/grin/test/Transformations/Optimising/ConstantFoldingSpec.hs
@@ -132,8 +132,8 @@ smallerThan transformed original  =
   let sizeReduced  = programSize transformed
       sizeOriginal = programSize original
   in
-    cover (sizeReduced == sizeOriginal) 0 "Non Reduced" $
-    cover (sizeReduced <  sizeOriginal) 1 "Reduced"     $
+    cover 0 (sizeReduced == sizeOriginal) "Non Reduced" $
+    cover 1 (sizeReduced <  sizeOriginal) "Reduced"     $
     (sizeReduced <= sizeOriginal)
 
 checkUniqueNames :: Exp -> Property
diff --git a/grin/test/Transformations/Simplifying/CaseSimplificationSpec.hs b/grin/test/Transformations/Simplifying/CaseSimplificationSpec.hs
index b38951dc..647a0b50 100644
--- a/grin/test/Transformations/Simplifying/CaseSimplificationSpec.hs
+++ b/grin/test/Transformations/Simplifying/CaseSimplificationSpec.hs
@@ -71,7 +71,7 @@ spec = do
 varTagCover :: Exp -> Property -> Property
 varTagCover exp =
   within 10000000 {-microsecond-} .
-  cover (getAny $ valuesInCases (Any . isVarTagNode) exp) 1 "Case with VarTagNode"
+  cover 1 (getAny $ valuesInCases (Any . isVarTagNode) exp) "Case with VarTagNode"
 
 programSizeDoesNotChange :: Exp -> Property
 programSizeDoesNotChange exp = varTagCover exp $ unchangedSize exp $ caseSimplification exp

From 60fce1c120072ac56e433c8f99f3def53366affc Mon Sep 17 00:00:00 2001
From: "L. S. Leary" <LSLeary@users.noreply.github.com>
Date: Sun, 10 Feb 2019 10:52:03 +1300
Subject: [PATCH 04/18] Misc.

---
 grin/app/GrinCLI.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/grin/app/GrinCLI.hs b/grin/app/GrinCLI.hs
index 967586f4..21769f5d 100644
--- a/grin/app/GrinCLI.hs
+++ b/grin/app/GrinCLI.hs
@@ -12,7 +12,7 @@ import Options.Applicative
 
 import Grin.Grin
 import Grin.PrimOpsPrelude
-import Grin.Parse hiding (value)
+import Grin.Parse -- hiding (value)
 import Grin.Nametable as Nametable
 import Pipeline.Pipeline
 

From 9927dcd99bbfe9f2f94dec515d342f16683d1a9b Mon Sep 17 00:00:00 2001
From: "L. S. Leary" <LSLeary@users.noreply.github.com>
Date: Mon, 11 Feb 2019 00:06:07 +1300
Subject: [PATCH 05/18] Get building with stack too (partial work).

---
 default.nix | 5 ++++-
 stack.yaml  | 4 +---
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/default.nix b/default.nix
index 598d76e0..ca00fbf5 100644
--- a/default.nix
+++ b/default.nix
@@ -13,6 +13,9 @@ hpkg.developPackage {
       llvm-config = pkgs.llvm_7;
     });
   };
-  modifier = drv: hlib.addBuildTool drv (import nix/llvm.nix {});
+  modifier = drv: hlib.addBuildTools drv [
+    (import nix/llvm.nix {})
+    pkgs.llvm_7
+  ];
   returnShellEnv = false;
 }
diff --git a/stack.yaml b/stack.yaml
index 088a22dc..8a2b8eb8 100644
--- a/stack.yaml
+++ b/stack.yaml
@@ -1,4 +1,4 @@
-resolver: nightly-2018-11-07
+resolver: nightly-2019-02-09
 
 # due to functor-infix
 allow-newer: true
@@ -16,8 +16,6 @@ extra-deps:
   - monad-gen-0.3.0.1
   - functor-infix-0.0.5
   - QuickCheck-GenT-0.2.0
-  - megaparsec-6.5.0
-  - neat-interpolation-0.3.2.2
   - set-extra-1.4.1
   - llvm-hs-pretty-0.6.1.0
 

From 044f8643cb28bc622c49bad236e9da4e6eac967d Mon Sep 17 00:00:00 2001
From: Luc Tielen <luc.tielen@kabisa.nl>
Date: Sun, 8 Dec 2019 11:52:14 +0100
Subject: [PATCH 06/18] Add end2end test output to gitignore

---
 .gitignore | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.gitignore b/.gitignore
index 5c9255bb..af377e61 100644
--- a/.gitignore
+++ b/.gitignore
@@ -24,6 +24,7 @@ output/
 *.agdai
 .output
 .grin-output/
+grin/.end-to-end-test/
 .vscode/
 *.out
 *.out.ll

From 9aceda4d00a3efc2c2bb685efa4d7af6fceafb63 Mon Sep 17 00:00:00 2001
From: Luc Tielen <luc.tielen@kabisa.nl>
Date: Sun, 8 Dec 2019 11:55:28 +0100
Subject: [PATCH 07/18] Pin to newer nixpkgs commit

---
 default.nix  |  1 +
 nix/pkgs.nix | 10 +++++-----
 2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/default.nix b/default.nix
index ca00fbf5..10bc67f8 100644
--- a/default.nix
+++ b/default.nix
@@ -12,6 +12,7 @@ hpkg.developPackage {
     llvm-hs = super.llvm-hs.override (oa: {
       llvm-config = pkgs.llvm_7;
     });
+    llvm-hs-pretty = hlib.unmarkBroken super.llvm-hs-pretty;
   };
   modifier = drv: hlib.addBuildTools drv [
     (import nix/llvm.nix {})
diff --git a/nix/pkgs.nix b/nix/pkgs.nix
index b9c74793..b8a8ec34 100644
--- a/nix/pkgs.nix
+++ b/nix/pkgs.nix
@@ -1,8 +1,8 @@
 let
-  pinned = (import <nixpkgs> {}).fetchFromGitHub {
-    owner  = "NixOS";
-    repo   = "nixpkgs-channels";
-    rev    = "ffc604e55790dbf575187738e1c3778231e8f5a9";
-    sha256 = "1kw37ab6abkrjn65zhh0jcnfb3bzk1p14d178sp8489kn9gxy12v";
+  commit = "2adf2d615cf8f6c6be49a0e54dc9ebf551dcf70f";
+  pinned = builtins.fetchTarball {
+    name   = "nixpkgs-19.09";
+    url = "https://github.com/nixos/nixpkgs/archive/${commit}.tar.gz";
+    sha256 = "0w8zgj38di4ssw6s0bxdb9rgksqfszsa3304863xic4bzsvkql9b";
   };
 in import pinned {}

From d2ff162ad465e8d01508c62a6fa2ad85832ec0ca Mon Sep 17 00:00:00 2001
From: Luc Tielen <luc.tielen@kabisa.nl>
Date: Sun, 8 Dec 2019 11:55:50 +0100
Subject: [PATCH 08/18] Add clang-7 as dependency

---
 default.nix | 1 +
 1 file changed, 1 insertion(+)

diff --git a/default.nix b/default.nix
index 10bc67f8..7ad132fa 100644
--- a/default.nix
+++ b/default.nix
@@ -16,6 +16,7 @@ hpkg.developPackage {
   };
   modifier = drv: hlib.addBuildTools drv [
     (import nix/llvm.nix {})
+    pkgs.clang_7
     pkgs.llvm_7
   ];
   returnShellEnv = false;

From 08e0bd3567656e9b2d68956528ac7f3e9e2f4b2f Mon Sep 17 00:00:00 2001
From: Luc Tielen <luc.tielen@kabisa.nl>
Date: Sun, 8 Dec 2019 17:19:56 +0100
Subject: [PATCH 09/18] Add more files to gitignore

---
 .gitignore | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/.gitignore b/.gitignore
index af377e61..4935ed89 100644
--- a/.gitignore
+++ b/.gitignore
@@ -18,6 +18,7 @@ cabal.sandbox.config
 *.eventlog
 .stack-work/
 cabal.project.local
+cabal.project.local~
 .HTF/
 output/
 *.ibc
@@ -29,3 +30,4 @@ grin/.end-to-end-test/
 *.out
 *.out.ll
 *.out.s
+.ghc.environment.*

From a2dfd1cded41adb9321651ffe56cf72a47c2e8e0 Mon Sep 17 00:00:00 2001
From: Luc Tielen <luc.tielen@kabisa.nl>
Date: Sun, 8 Dec 2019 17:20:16 +0100
Subject: [PATCH 10/18] Update Diff dependency

---
 grin/grin.cabal | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/grin/grin.cabal b/grin/grin.cabal
index 7f1f6e12..f31975bb 100644
--- a/grin/grin.cabal
+++ b/grin/grin.cabal
@@ -166,7 +166,7 @@ library
     quickcheck-instances,
     neat-interpolation,
     template-haskell,
-    Diff,
+    Diff == 0.4.*,
     random,
     set-extra,
     deepseq,

From 835678650c2690c71017d107639c1461b92329aa Mon Sep 17 00:00:00 2001
From: Luc Tielen <luc.tielen@kabisa.nl>
Date: Sun, 8 Dec 2019 17:22:59 +0100
Subject: [PATCH 11/18] Use GHC865 with nix, point to same llvm-hs fork as
 stack

---
 default.nix            |  9 +++++----
 nix/llvm-hs-pretty.nix | 19 +++++++++++++++++++
 nix/llvm-hs.nix        |  7 +++++++
 shell.nix              |  2 +-
 4 files changed, 32 insertions(+), 5 deletions(-)
 create mode 100644 nix/llvm-hs-pretty.nix
 create mode 100644 nix/llvm-hs.nix

diff --git a/default.nix b/default.nix
index 7ad132fa..177a0ae8 100644
--- a/default.nix
+++ b/default.nix
@@ -2,17 +2,18 @@
 
 let
   hlib = pkgs.haskell.lib;
-  hpkg = pkgs.haskell.packages.ghc844;
+  hpkg = pkgs.haskell.packages.ghc865;
+  llvm-hs = import ./nix/llvm-hs.nix;
 in
 
 hpkg.developPackage {
   root = ./grin;
   overrides = self: super: {
-    Diff = hlib.dontCheck super.Diff;
-    llvm-hs = super.llvm-hs.override (oa: {
+    llvm-hs = hlib.dontCheck (self.callCabal2nix "llvm-hs" "${llvm-hs}/llvm-hs" {
       llvm-config = pkgs.llvm_7;
     });
-    llvm-hs-pretty = hlib.unmarkBroken super.llvm-hs-pretty;
+    llvm-hs-pure = self.callCabal2nix "llvm-hs-pure" "${llvm-hs}/llvm-hs-pure" {};
+    llvm-hs-pretty = self.callPackage ./nix/llvm-hs-pretty.nix {};
   };
   modifier = drv: hlib.addBuildTools drv [
     (import nix/llvm.nix {})
diff --git a/nix/llvm-hs-pretty.nix b/nix/llvm-hs-pretty.nix
new file mode 100644
index 00000000..03b9bb35
--- /dev/null
+++ b/nix/llvm-hs-pretty.nix
@@ -0,0 +1,19 @@
+{ mkDerivation, array, base, bytestring, directory, filepath
+, llvm-hs, llvm-hs-pure, mtl, prettyprinter, tasty, tasty-golden
+, tasty-hspec, tasty-hunit, text, transformers, stdenv
+}:
+mkDerivation {
+  pname = "llvm-hs-pretty";
+  version = "0.6.1.0";
+  sha256 = "12w1rkkaf50jl2vdkyk4xpvjmsxzjbfkdyklaq5p6b8ykw872pda";
+  libraryHaskellDepends = [
+    array base bytestring llvm-hs-pure prettyprinter text
+  ];
+  testHaskellDepends = [
+    base directory filepath llvm-hs llvm-hs-pure mtl tasty tasty-golden
+    tasty-hspec tasty-hunit text transformers
+  ];
+  description = "A pretty printer for LLVM IR";
+  license = stdenv.lib.licenses.mit;
+  hydraPlatforms = stdenv.lib.platforms.none;
+}
diff --git a/nix/llvm-hs.nix b/nix/llvm-hs.nix
new file mode 100644
index 00000000..ec6dea2c
--- /dev/null
+++ b/nix/llvm-hs.nix
@@ -0,0 +1,7 @@
+let
+  url = "https://github.com/csabahruska/llvm-hs";
+  ref = "llvm-7";
+  rev = "868e23a13942703255979369defdb49ac57b6866";
+  repo = builtins.fetchGit { inherit url ref rev; };
+in
+  repo
diff --git a/shell.nix b/shell.nix
index c10737f8..981d7045 100644
--- a/shell.nix
+++ b/shell.nix
@@ -1,7 +1,7 @@
 { pkgs ? import nix/pkgs.nix }:
 
 let grin = import ./. { inherit pkgs; };
-in pkgs.haskell.packages.ghc844.shellFor {
+in pkgs.haskell.packages.ghc865.shellFor {
   withHoogle = true;
   packages = p: [ grin ];
   inherit (grin.env) nativeBuildInputs;

From 0784573caceae77353e34e4e7b4c388f9d4a4f15 Mon Sep 17 00:00:00 2001
From: Luc Tielen <luc.tielen@kabisa.nl>
Date: Sun, 8 Dec 2019 17:28:05 +0100
Subject: [PATCH 12/18] Always use same compiler in shell.nix and default.nix

---
 default.nix | 4 ++--
 shell.nix   | 8 ++++++--
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/default.nix b/default.nix
index 177a0ae8..d3a82782 100644
--- a/default.nix
+++ b/default.nix
@@ -1,8 +1,8 @@
-{ pkgs ? import nix/pkgs.nix }:
+{ compiler ? "ghc865", pkgs ? import nix/pkgs.nix }:
 
 let
   hlib = pkgs.haskell.lib;
-  hpkg = pkgs.haskell.packages.ghc865;
+  hpkg = pkgs.haskell.packages."${compiler}";
   llvm-hs = import ./nix/llvm-hs.nix;
 in
 
diff --git a/shell.nix b/shell.nix
index 981d7045..afda174f 100644
--- a/shell.nix
+++ b/shell.nix
@@ -1,7 +1,11 @@
 { pkgs ? import nix/pkgs.nix }:
 
-let grin = import ./. { inherit pkgs; };
-in pkgs.haskell.packages.ghc865.shellFor {
+let
+  compiler = "ghc865";
+  grin = import ./. { inherit compiler pkgs; };
+in
+
+pkgs.haskell.packages."${compiler}".shellFor {
   withHoogle = true;
   packages = p: [ grin ];
   inherit (grin.env) nativeBuildInputs;

From 16fc9ee5365b1e7b53d80d0c08d5a1fa03bd8d3e Mon Sep 17 00:00:00 2001
From: Luc Tielen <luc.tielen@kabisa.nl>
Date: Sun, 8 Dec 2019 17:52:32 +0100
Subject: [PATCH 13/18] Provide cabal and ghcid when in nix-shell

---
 shell.nix | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/shell.nix b/shell.nix
index afda174f..cc2da059 100644
--- a/shell.nix
+++ b/shell.nix
@@ -2,11 +2,13 @@
 
 let
   compiler = "ghc865";
+  hpkg = pkgs.haskell.packages."${compiler}";
   grin = import ./. { inherit compiler pkgs; };
 in
 
-pkgs.haskell.packages."${compiler}".shellFor {
+hpkg.shellFor {
   withHoogle = true;
   packages = p: [ grin ];
+  buildInputs = with hpkg; [ cabal-install ghcid ];
   inherit (grin.env) nativeBuildInputs;
 }

From 692329a39598717f7a10c8a492ce5ab03bddfe5c Mon Sep 17 00:00:00 2001
From: Luc Tielen <luc.tielen@kabisa.nl>
Date: Sun, 8 Dec 2019 18:21:01 +0100
Subject: [PATCH 14/18] Point to lts-14.16 stackage version

---
 stack.yaml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/stack.yaml b/stack.yaml
index fd5a9caa..25a6097b 100644
--- a/stack.yaml
+++ b/stack.yaml
@@ -1,4 +1,4 @@
-resolver: nightly-2019-02-09
+resolver: lts-14.16
 
 # due to functor-infix
 allow-newer: true

From 70625b81d87a17bcd9ce3e2dd911321d1ec4ca95 Mon Sep 17 00:00:00 2001
From: Luc Tielen <luc.tielen@kabisa.nl>
Date: Tue, 10 Dec 2019 21:39:47 +0100
Subject: [PATCH 15/18] Update dependency versions

---
 grin/grin.cabal | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/grin/grin.cabal b/grin/grin.cabal
index f31975bb..2b7f082b 100644
--- a/grin/grin.cabal
+++ b/grin/grin.cabal
@@ -162,11 +162,11 @@ library
     hspec-core,
     extra,
     logict,
-    QuickCheck ==2.12.*,
+    QuickCheck ==2.13.*,
     quickcheck-instances,
     neat-interpolation,
     template-haskell,
-    Diff == 0.4.*,
+    Diff,
     random,
     set-extra,
     deepseq,
@@ -214,7 +214,7 @@ test-suite grin-test
                      , hspec
                      , hspec-core
                      , hspec-discover
-                     , QuickCheck ==2.12.*
+                     , QuickCheck ==2.13.*
                      , deepseq
                      , vector
                      , text

From a730ec167cc70487b5027d62ec80b708570ad4f8 Mon Sep 17 00:00:00 2001
From: Luc Tielen <luc.tielen@kabisa.nl>
Date: Wed, 11 Dec 2019 20:59:17 +0100
Subject: [PATCH 16/18] Use haskell.nix to keep stack and nix approaches in
 sync

---
 default.nix              | 33 +++++++++++----------------------
 nix/haskell-nix-src.json |  7 +++++++
 nix/haskell.nix          |  8 ++++++++
 nix/llvm-hs-pretty.nix   | 19 -------------------
 nix/llvm-hs.nix          |  7 -------
 nix/llvm.nix             |  2 +-
 nix/packages.nix         | 10 ++++++++++
 nix/pkgs.nix             |  8 --------
 shell.nix                | 22 ++++++++++------------
 9 files changed, 47 insertions(+), 69 deletions(-)
 create mode 100644 nix/haskell-nix-src.json
 create mode 100644 nix/haskell.nix
 delete mode 100644 nix/llvm-hs-pretty.nix
 delete mode 100644 nix/llvm-hs.nix
 create mode 100644 nix/packages.nix
 delete mode 100644 nix/pkgs.nix

diff --git a/default.nix b/default.nix
index d3a82782..84eb41b3 100644
--- a/default.nix
+++ b/default.nix
@@ -1,24 +1,13 @@
-{ compiler ? "ghc865", pkgs ? import nix/pkgs.nix }:
-
 let
-  hlib = pkgs.haskell.lib;
-  hpkg = pkgs.haskell.packages."${compiler}";
-  llvm-hs = import ./nix/llvm-hs.nix;
-in
-
-hpkg.developPackage {
-  root = ./grin;
-  overrides = self: super: {
-    llvm-hs = hlib.dontCheck (self.callCabal2nix "llvm-hs" "${llvm-hs}/llvm-hs" {
-      llvm-config = pkgs.llvm_7;
-    });
-    llvm-hs-pure = self.callCabal2nix "llvm-hs-pure" "${llvm-hs}/llvm-hs-pure" {};
-    llvm-hs-pretty = self.callPackage ./nix/llvm-hs-pretty.nix {};
+  haskell = import ./nix/haskell.nix;
+  llvm-overlay = self: super: {
+    llvm-config = self.llvm_7;
   };
-  modifier = drv: hlib.addBuildTools drv [
-    (import nix/llvm.nix {})
-    pkgs.clang_7
-    pkgs.llvm_7
-  ];
-  returnShellEnv = false;
-}
+  extra-overlays = [ llvm-overlay ];
+  pkgs = import ./nix/packages.nix (haskell // {
+    overlays = haskell.overlays ++ extra-overlays;
+  });
+in
+  pkgs.haskell-nix.stackProject {
+    src = pkgs.haskell-nix.haskellLib.cleanGit { src = ./.; };
+  }
diff --git a/nix/haskell-nix-src.json b/nix/haskell-nix-src.json
new file mode 100644
index 00000000..b7744e52
--- /dev/null
+++ b/nix/haskell-nix-src.json
@@ -0,0 +1,7 @@
+{
+  "url": "https://github.com/input-output-hk/haskell.nix",
+  "rev": "ebdc0030e6973629c1ed7dba53c1b1d154c3e75e",
+  "date": "2019-12-11T01:12:46+00:00",
+  "sha256": "1q25sw8kz7r0wwzq780qq1cgsiy1g7iwnywckixa28psim8rp2nw",
+  "fetchSubmodules": false
+}
diff --git a/nix/haskell.nix b/nix/haskell.nix
new file mode 100644
index 00000000..0770819d
--- /dev/null
+++ b/nix/haskell.nix
@@ -0,0 +1,8 @@
+let
+  spec = builtins.fromJSON (builtins.readFile ./haskell-nix-src.json);
+  haskell-nix-src = builtins.fetchGit {
+    name = "haskell-lib";
+    inherit (spec) url rev;
+  };
+in
+  import haskell-nix-src
diff --git a/nix/llvm-hs-pretty.nix b/nix/llvm-hs-pretty.nix
deleted file mode 100644
index 03b9bb35..00000000
--- a/nix/llvm-hs-pretty.nix
+++ /dev/null
@@ -1,19 +0,0 @@
-{ mkDerivation, array, base, bytestring, directory, filepath
-, llvm-hs, llvm-hs-pure, mtl, prettyprinter, tasty, tasty-golden
-, tasty-hspec, tasty-hunit, text, transformers, stdenv
-}:
-mkDerivation {
-  pname = "llvm-hs-pretty";
-  version = "0.6.1.0";
-  sha256 = "12w1rkkaf50jl2vdkyk4xpvjmsxzjbfkdyklaq5p6b8ykw872pda";
-  libraryHaskellDepends = [
-    array base bytestring llvm-hs-pure prettyprinter text
-  ];
-  testHaskellDepends = [
-    base directory filepath llvm-hs llvm-hs-pure mtl tasty tasty-golden
-    tasty-hspec tasty-hunit text transformers
-  ];
-  description = "A pretty printer for LLVM IR";
-  license = stdenv.lib.licenses.mit;
-  hydraPlatforms = stdenv.lib.platforms.none;
-}
diff --git a/nix/llvm-hs.nix b/nix/llvm-hs.nix
deleted file mode 100644
index ec6dea2c..00000000
--- a/nix/llvm-hs.nix
+++ /dev/null
@@ -1,7 +0,0 @@
-let
-  url = "https://github.com/csabahruska/llvm-hs";
-  ref = "llvm-7";
-  rev = "868e23a13942703255979369defdb49ac57b6866";
-  repo = builtins.fetchGit { inherit url ref rev; };
-in
-  repo
diff --git a/nix/llvm.nix b/nix/llvm.nix
index a8c389cc..19c19f6d 100644
--- a/nix/llvm.nix
+++ b/nix/llvm.nix
@@ -1,4 +1,4 @@
-{ pkgs ? import ./pkgs.nix }:
+{ pkgs ? import ./packages.nix {} }:
 
 pkgs.runCommand
   "llvm-7-links"
diff --git a/nix/packages.nix b/nix/packages.nix
new file mode 100644
index 00000000..d9a729f3
--- /dev/null
+++ b/nix/packages.nix
@@ -0,0 +1,10 @@
+let
+  commit = "4c6e9a553872366e485766fa8b574b54b15957f8";
+  nixpkgs = builtins.fetchTarball {
+    name = "nixpkgs-19.09";
+    url = "https://github.com/nixos/nixpkgs/archive/${commit}.tar.gz";
+    sha256 = "1az9yg2lwwfw3aypi6bdsk7ghld2963vqdp8ajkxciyxdfkaxb3b";
+  };
+  pkgs = import nixpkgs;
+in
+  pkgs
diff --git a/nix/pkgs.nix b/nix/pkgs.nix
deleted file mode 100644
index b8a8ec34..00000000
--- a/nix/pkgs.nix
+++ /dev/null
@@ -1,8 +0,0 @@
-let
-  commit = "2adf2d615cf8f6c6be49a0e54dc9ebf551dcf70f";
-  pinned = builtins.fetchTarball {
-    name   = "nixpkgs-19.09";
-    url = "https://github.com/nixos/nixpkgs/archive/${commit}.tar.gz";
-    sha256 = "0w8zgj38di4ssw6s0bxdb9rgksqfszsa3304863xic4bzsvkql9b";
-  };
-in import pinned {}
diff --git a/shell.nix b/shell.nix
index cc2da059..6cc8d1be 100644
--- a/shell.nix
+++ b/shell.nix
@@ -1,14 +1,12 @@
-{ pkgs ? import nix/pkgs.nix }:
-
 let
-  compiler = "ghc865";
-  hpkg = pkgs.haskell.packages."${compiler}";
-  grin = import ./. { inherit compiler pkgs; };
+  pkgs = import ./nix/packages.nix {};
+  llvm-links = import ./nix/llvm.nix { inherit pkgs; };
+  haskellPkgs = import ./.;
 in
-
-hpkg.shellFor {
-  withHoogle = true;
-  packages = p: [ grin ];
-  buildInputs = with hpkg; [ cabal-install ghcid ];
-  inherit (grin.env) nativeBuildInputs;
-}
+  haskellPkgs.shellFor {
+    buildInputs = with pkgs.haskellPackages; [
+      llvm-links
+      hlint
+      ghcid
+    ];
+  }

From 90a70938b853e5e1afae3dea9cae8833beaded87 Mon Sep 17 00:00:00 2001
From: Luc Tielen <luc.tielen@kabisa.nl>
Date: Sat, 14 Dec 2019 10:26:19 +0100
Subject: [PATCH 17/18] Allow specifying llvm tooling via env vars

---
 grin/src/Pipeline/Pipeline.hs | 15 ++++++++++-----
 nix/llvm.nix                  | 11 -----------
 shell.nix                     |  6 ++++--
 3 files changed, 14 insertions(+), 18 deletions(-)
 delete mode 100644 nix/llvm.nix

diff --git a/grin/src/Pipeline/Pipeline.hs b/grin/src/Pipeline/Pipeline.hs
index fa5192e0..d96cbd57 100644
--- a/grin/src/Pipeline/Pipeline.hs
+++ b/grin/src/Pipeline/Pipeline.hs
@@ -82,6 +82,7 @@ import qualified AbstractInterpretation.EffectTracking.CodeGenBase   as ET
 import qualified AbstractInterpretation.Sharing.CodeGen              as Sharing
 import qualified Reducer.LLVM.CodeGen as CGLLVM
 import qualified Reducer.LLVM.JIT as JITLLVM
+import System.Environment ( lookupEnv )
 import System.Directory
 import qualified System.Process
 import Data.Bifunctor
@@ -718,23 +719,27 @@ saveLLVM path = do
   pipelineLog "* to LLVM *"
   void $ liftIO $ CGLLVM.toLLVM llName code
   pipelineLog"* LLVM X64 codegen *"
-  callCommand $ printf "opt-7 -O3 %s | llc-7 -o %s" llName (sName :: String)
+  llcExe <- liftIO $ fromMaybe "llc-7" <$> lookupEnv "GRIN_LLC"
+  optExe <- liftIO $ fromMaybe "opt-7" <$> lookupEnv "GRIN_OPT"
+  callCommand $ printf "%s -O3 %s | %s -o %s" optExe llName llcExe (sName :: String)
 
 saveExecutable :: Bool -> Path -> PipelineM ()
 saveExecutable debugSymbols path = do
   pipelineLog "* generate llvm x64 optcode *"
   let grinOptCodePath = Rel "grin-opt-code"
+  clangExe <- liftIO $ fromMaybe "clang-7" <$> lookupEnv "GRIN_CC"
+  llcExe <- liftIO $ fromMaybe "llc-7" <$> lookupEnv "GRIN_LLC"
   pipelineStep $ SaveLLVM grinOptCodePath
   grinOptCodeFile <- relPath grinOptCodePath
   fname <- relPath path
   pipelineLog "* generate executable *"
   callCommand $ printf
-    ("llc-7 -O3 -relocation-model=pic -filetype=obj %s.ll" ++ if debugSymbols then " -debugger-tune=gdb" else "")
-    grinOptCodeFile
+    ("%s -O3 -relocation-model=pic -filetype=obj %s.ll" ++ if debugSymbols then " -debugger-tune=gdb" else "")
+    llcExe grinOptCodeFile
   cfg <- ask
   callCommand $ printf
-    ("clang-7 -O3 %s %s.o -s -o %s" ++ if debugSymbols then " -g" else "")
-    (intercalate " " $ _poCFiles cfg) grinOptCodeFile fname
+    ("%s -O3 %s %s.o -s -o %s" ++ if debugSymbols then " -g" else "")
+    clangExe (intercalate " " $ _poCFiles cfg) grinOptCodeFile fname
 
 debugTransformation :: (Exp -> Exp) -> PipelineM ()
 debugTransformation t = do
diff --git a/nix/llvm.nix b/nix/llvm.nix
deleted file mode 100644
index 19c19f6d..00000000
--- a/nix/llvm.nix
+++ /dev/null
@@ -1,11 +0,0 @@
-{ pkgs ? import ./packages.nix {} }:
-
-pkgs.runCommand
-  "llvm-7-links"
-  { buildInputs = [ pkgs.llvm_7 ]; }
-  ''
-    mkdir -p $out/bin
-    cd $out/bin
-    ln -s ${pkgs.llvm_7}/bin/llc llc-7
-    ln -s ${pkgs.llvm_7}/bin/opt opt-7
-  ''
diff --git a/shell.nix b/shell.nix
index 6cc8d1be..5dcd9e5e 100644
--- a/shell.nix
+++ b/shell.nix
@@ -1,12 +1,14 @@
 let
   pkgs = import ./nix/packages.nix {};
-  llvm-links = import ./nix/llvm.nix { inherit pkgs; };
   haskellPkgs = import ./.;
 in
   haskellPkgs.shellFor {
     buildInputs = with pkgs.haskellPackages; [
-      llvm-links
       hlint
       ghcid
     ];
+
+    GRIN_CC = "${pkgs.clang_7}/bin/clang";
+    GRIN_OPT = "${pkgs.llvm_7}/bin/opt";
+    GRIN_LLC = "${pkgs.llvm_7}/bin/llc";
   }

From fa7d5a2f0f642ae2339058911268b26b3f48c477 Mon Sep 17 00:00:00 2001
From: Luc Tielen <luc.tielen@kabisa.nl>
Date: Tue, 17 Dec 2019 18:35:04 +0100
Subject: [PATCH 18/18] Minor cleanups to cabal file

---
 grin/app/CLI/Lib.hs | 2 +-
 grin/grin.cabal     | 8 ++++----
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/grin/app/CLI/Lib.hs b/grin/app/CLI/Lib.hs
index d1b334a7..cd452ddf 100644
--- a/grin/app/CLI/Lib.hs
+++ b/grin/app/CLI/Lib.hs
@@ -17,7 +17,7 @@ import System.IO
 
 import Grin.Grin
 import Grin.PrimOpsPrelude
-import Grin.Parse -- hiding (value)
+import Grin.Parse
 import Grin.Nametable as Nametable
 import Pipeline.Pipeline
 
diff --git a/grin/grin.cabal b/grin/grin.cabal
index 2b7f082b..d4d3c7f7 100644
--- a/grin/grin.cabal
+++ b/grin/grin.cabal
@@ -131,7 +131,7 @@ library
     bimap,
     mtl,
     comonad,
-    megaparsec ==7.0.*,
+    megaparsec,
     pretty-show,
     vector,
     deepseq,
@@ -162,7 +162,7 @@ library
     hspec-core,
     extra,
     logict,
-    QuickCheck ==2.13.*,
+    QuickCheck,
     quickcheck-instances,
     neat-interpolation,
     template-haskell,
@@ -182,7 +182,7 @@ executable grin
                      , grin
                      , recursion-schemes
                      , ansi-wl-pprint
-                     , megaparsec ==7.0.*
+                     , megaparsec
                      , containers
                      , process
                      , pretty-show
@@ -214,7 +214,7 @@ test-suite grin-test
                      , hspec
                      , hspec-core
                      , hspec-discover
-                     , QuickCheck ==2.13.*
+                     , QuickCheck
                      , deepseq
                      , vector
                      , text