diff --git a/pkgs/development/compilers/elm/default.nix b/pkgs/development/compilers/elm/default.nix
index 51f76f1108a..70be5a95105 100644
--- a/pkgs/development/compilers/elm/default.nix
+++ b/pkgs/development/compilers/elm/default.nix
@@ -1,10 +1,12 @@
-{ lib, stdenv, buildEnv, haskell, nodejs, fetchurl, makeWrapper }:
+{ lib, stdenv, buildEnv, haskell, nodejs, fetchurl, makeWrapper, git }:
 
 # To update:
-# 1) Update versions in ./update-elm.rb and run it.
-# 2) Checkout elm-reactor and run `elm-package install -y` inside.
-# 3) Run ./elm2nix.rb in elm-reactor's directory.
-# 4) Move the resulting 'package.nix' to 'packages/elm-reactor-elm.nix'.
+
+# 1) Modify ./update.sh and run it
+# 2) XXX: generate packages/elm-elm.nix
+# 3) XXX: versions.dat
+
+# Notes:
 
 # the elm binary embeds a piece of pre-compiled elm code, used by 'elm
 # reactor'. this means that the build process for 'elm' effectively
@@ -48,22 +50,25 @@ let
                in ''
                  mkdir -p .elm/${ver}/package/${name}
                  cp -R ${pkg} .elm/${ver}/package/${name}/${info.version}
-                 chmod -R +w .elm/${ver}/package/${name}/${info.version}
                '') deps;
-    in ''
+    in (lib.concatStrings cmds) + ''
       mkdir -p .elm/${ver}/package;
-      ln -s ${versionsDat} .elm/${ver}/package/versions.dat;
-    '' + lib.concatStrings cmds;
+      cp ${versionsDat} .elm/${ver}/package/versions.dat;
+      chmod -R +w .elm
+    '';
 
   hsPkgs = haskell.packages.ghc822.override {
-    overrides = self: super:
-      let hlib = haskell.lib;
-          elmPkgs = {
-            elm = hlib.overrideCabal (self.callPackage ./packages/elm.nix { }) {
+    overrides = self: super: with haskell.lib;
+      let elmPkgs = {
+            elm = overrideCabal (self.callPackage ./packages/elm.nix { }) (attrs: {
+              # sadly with parallelism most of the time breaks compilation
+              enableParallelBuilding = false;
               preConfigure = ''
                 export ELM_HOME=`pwd`/.elm
               '' + (makeDotElm "0.19.0" (import ./packages/elm-elm.nix));
-            };
+            });
+
+
 
             /*
             This is not a core Elm package, and it's hosted on GitHub.
@@ -71,14 +76,28 @@ let
 
                 cabal2nix --jailbreak --revision refs/tags/foo http://github.com/avh4/elm-format > packages/elm-format.nix
 
-            where foo is a tag for a new version, for example "0.3.1-alpha".
+            where foo is a tag for a new version, for example "0.8.0".
             */
-            elm-format = self.callPackage ./packages/elm-format.nix { };
-            elm-interface-to-json = self.callPackage ./packages/elm-interface-to-json.nix {};
+            elm-format = overrideCabal (self.callPackage ./packages/elm-format.nix {  }) (drv: {
+              # https://github.com/avh4/elm-format/issues/529
+              patchPhase = ''
+                cat >Setup.hs <<EOF
+                import Distribution.Simple
+                main = defaultMain
+                EOF
+
+                sed -i '/Build_elm_format/d' elm-format.cabal
+                sed -i 's/Build_elm_format.gitDescribe/""/' src/ElmFormat/Version.hs
+                sed -i '/Build_elm_format/d' src/ElmFormat/Version.hs
+              '';
+            });
           };
       in elmPkgs // {
         inherit elmPkgs;
         elmVersion = elmPkgs.elm.version;
+
+        # Needed for elm-format
+        indents = self.callPackage ./packages/indents.nix {};
       };
   };
 in hsPkgs.elmPkgs
diff --git a/pkgs/development/compilers/elm/packages/elm-format.nix b/pkgs/development/compilers/elm/packages/elm-format.nix
index 56db835ac10..86d99abab5a 100644
--- a/pkgs/development/compilers/elm/packages/elm-format.nix
+++ b/pkgs/development/compilers/elm/packages/elm-format.nix
@@ -6,14 +6,12 @@
 }:
 mkDerivation {
   pname = "elm-format";
-  version = "0.7.0";
+  version = "0.8.0";
   src = fetchgit {
     url = "http://github.com/avh4/elm-format";
-    sha256 = "1snl2lrrzdwgzi68agi3sdw84aslj04pzzxpm1mam9ic6dzhn3jf";
-    rev = "da4b415c6a2b7e77b7d9f00beca3e45230e603fb";
+    sha256 = "1w79xvsyq98vfz3jb4sv8433vdh6pcg8s7yh54lcxzr1p08yhsb6";
+    rev = "f19ac28046d7e83ff95f845849c033cc616f1bd6";
   };
-
-  doHaddock = false;
   isLibrary = true;
   isExecutable = true;
   setupHaskellDepends = [ base Cabal directory filepath process ];
@@ -27,15 +25,10 @@ mkDerivation {
     base cmark containers HUnit mtl parsec QuickCheck quickcheck-io
     split tasty tasty-golden tasty-hunit tasty-quickcheck text
   ];
+  doHaddock = false;
   jailbreak = true;
-  postInstall = ''
-    ln -s $out/bin/elm-format-0.18 $out/bin/elm-format
-  '';
-  postPatch = ''
-    sed -i "s|desc <-.*||" ./Setup.hs
-    sed -i "s|gitDescribe = .*|gitDescribe = \\\\\"da4b415c\\\\\"\"|" ./Setup.hs
-  '';
-  homepage = http://elm-lang.org;
+  doCheck = false;
+  homepage = "http://elm-lang.org";
   description = "A source code formatter for Elm";
   license = stdenv.lib.licenses.bsd3;
 }
diff --git a/pkgs/development/compilers/elm/packages/elm-interface-to-json.nix b/pkgs/development/compilers/elm/packages/elm-interface-to-json.nix
deleted file mode 100644
index 3f797b7a236..00000000000
--- a/pkgs/development/compilers/elm/packages/elm-interface-to-json.nix
+++ /dev/null
@@ -1,24 +0,0 @@
-{ mkDerivation, aeson, aeson-pretty, base, binary, bytestring
-, concatenative, containers, directory, either, elm-compiler
-, filemanip, filepath, indents, optparse-applicative, parsec
-, stdenv, text, transformers, fetchgit
-}:
-mkDerivation {
-  pname = "elm-interface-to-json";
-  version = "0.1.0.0";
-  src = fetchgit {
-    url = "https://github.com/stoeffel/elm-interface-to-json";
-    sha256 = "1izc78w91m7nrc9i2b3lgy3kyjsy4d5mkkblx96ws0bp3dpm5f9k";
-    rev = "9884c1c997a55f11cf7c3d99a8afa72cf2e97323";
-  };
-  isLibrary = false;
-  isExecutable = true;
-  jailbreak = true;
-  executableHaskellDepends = [
-    aeson aeson-pretty base binary bytestring concatenative containers
-    directory either elm-compiler filemanip filepath indents
-    optparse-applicative parsec text transformers
-  ];
-  homepage = "https://github.com/githubuser/elm-interface-to-json#readme";
-  license = stdenv.lib.licenses.bsd3;
-}
diff --git a/pkgs/development/compilers/elm/packages/elm-reactor-elm.nix b/pkgs/development/compilers/elm/packages/elm-reactor-elm.nix
deleted file mode 100644
index 90c8956323b..00000000000
--- a/pkgs/development/compilers/elm/packages/elm-reactor-elm.nix
+++ /dev/null
@@ -1,22 +0,0 @@
-{
-  "elm-lang/virtual-dom" = {
-    version = "2.0.1";
-    sha256 = "19nfjx072m7a7bx8flc50vbmiww172jmscyq9x91cr2kby5hvbw3";
-  };
-  "evancz/elm-markdown" = {
-    version = "3.0.1";
-    sha256 = "144lzpcapf2mhqiz90mkllmm4skrcs0iha1daps42qn3xps7hvmj";
-  };
-  "elm-lang/html" = {
-    version = "2.0.0";
-    sha256 = "05sqjd5n8jnq4lv5v0ipcg98b8im1isnnl4wns1zzn4w5nbrjjzi";
-  };
-  "elm-lang/svg" = {
-    version = "2.0.0";
-    sha256 = "1c7p967n1yhynravqwgh80vprwz7r2r1n0x3icn5wzk9iaqs069l";
-  };
-  "elm-lang/core" = {
-    version = "5.0.0";
-    sha256 = "0gqyc09bh43pi7r2cizyjm5y0zpgarv3is17dl325qvxb9s1y2gn";
-  };
-}
diff --git a/pkgs/development/compilers/elm/packages/elm-reactor.nix b/pkgs/development/compilers/elm/packages/elm-reactor.nix
deleted file mode 100644
index 41611b3cdd0..00000000000
--- a/pkgs/development/compilers/elm/packages/elm-reactor.nix
+++ /dev/null
@@ -1,28 +0,0 @@
-{ mkDerivation, aeson, base, blaze-html, blaze-markup, bytestring
-, cmdargs, containers, directory, elm-compiler, elm-package
-, fetchgit, file-embed, filepath, fsnotify, mtl, process, snap-core
-, snap-server, stdenv, template-haskell, text, time, transformers
-, unordered-containers, utf8-string, websockets, websockets-snap
-}:
-mkDerivation {
-  pname = "elm-reactor";
-  version = "0.18";
-  src = fetchgit {
-    url = "https://github.com/elm-lang/elm-reactor";
-    sha256 = "0lpidsckyfcr8d6bln735d98dx7ga7j1vyssw0qsv8ijj18gxx65";
-    rev = "c519d4ec0aaf2f043a416fe858346b0181eca516";
-  };
-  isLibrary = false;
-  isExecutable = true;
-  executableHaskellDepends = [
-    aeson base blaze-html blaze-markup bytestring cmdargs containers
-    directory elm-compiler elm-package file-embed filepath fsnotify mtl
-    process snap-core snap-server template-haskell text time
-    transformers unordered-containers utf8-string websockets
-    websockets-snap
-  ];
-  jailbreak = true;
-  homepage = http://elm-lang.org;
-  description = "Interactive development tool for Elm programs";
-  license = stdenv.lib.licenses.bsd3;
-}
diff --git a/pkgs/development/compilers/elm/packages/indents.nix b/pkgs/development/compilers/elm/packages/indents.nix
new file mode 100644
index 00000000000..6bf7fa7890e
--- /dev/null
+++ b/pkgs/development/compilers/elm/packages/indents.nix
@@ -0,0 +1,11 @@
+{ mkDerivation, base, concatenative, mtl, parsec, stdenv }:
+mkDerivation {
+  pname = "indents";
+  version = "0.3.3";
+  sha256 = "b61f51ac894609cb5571cc3ded12db5de97185a8de236c69ec24c87457109f9a";
+  libraryHaskellDepends = [ base concatenative mtl parsec ];
+  doCheck = false;
+  homepage = "http://patch-tag.com/r/salazar/indents";
+  description = "indentation sensitive parser-combinators for parsec";
+  license = stdenv.lib.licenses.bsd3;
+}
diff --git a/pkgs/development/compilers/elm/packages/release.nix b/pkgs/development/compilers/elm/packages/release.nix
deleted file mode 100644
index fd4e08fff09..00000000000
--- a/pkgs/development/compilers/elm/packages/release.nix
+++ /dev/null
@@ -1,13 +0,0 @@
-# This file is auto-generated by ./update-elm.rb.
-# Please, do not modify it by hand!
-{ callPackage }:
-{
-  version = "0.18.0";
-  packages = {
-    elm-compiler = callPackage ./elm-compiler.nix { };
-    elm-package = callPackage ./elm-package.nix { };
-    elm-make = callPackage ./elm-make.nix { };
-    elm-reactor = callPackage ./elm-reactor.nix { };
-    elm-repl = callPackage ./elm-repl.nix { };
-  };
-}
diff --git a/pkgs/development/compilers/elm/update.sh b/pkgs/development/compilers/elm/update.sh
new file mode 100755
index 00000000000..02e5bdc9b58
--- /dev/null
+++ b/pkgs/development/compilers/elm/update.sh
@@ -0,0 +1,3 @@
+cabal2nix https://github.com/elm/compiler --revision  32059a289d27e303fa1665e9ada0a52eb688f302 > packages/elm.nix
+cabal2nix --no-check cabal://indents-0.3.3 > packages/indents.nix
+cabal2nix --no-haddock --no-check --jailbreak --revision refs/tags/0.8.0 http://github.com/avh4/elm-format > packages/elm-format.nix