diff --git a/pins/haskell-nix-src.json b/pins/haskell-nix-src.json
new file mode 100644
index 0000000..b6387fa
--- /dev/null
+++ b/pins/haskell-nix-src.json
@@ -0,0 +1,7 @@
+{
+  "url": "https://github.com/input-output-hk/haskell.nix",
+  "rev": "b54de7b002026d70666ec7d0bee8f20cc53ceb23",
+  "date": "2019-06-11T10:59:50+12:00",
+  "sha256": "0k9psmmds5bqwwa3bn3qm0mwpq2grjrvcz0665df8xxl6n11salp",
+  "fetchSubmodules": false
+}
diff --git a/pins/iohk-nix-src.json b/pins/iohk-nix-src.json
index 7ce8f3e..8b09a73 100644
--- a/pins/iohk-nix-src.json
+++ b/pins/iohk-nix-src.json
@@ -1,7 +1,7 @@
 {
   "url": "https://github.com/input-output-hk/iohk-nix",
-  "rev": "4608304d2e02f0f8384d3aa7b7d89ffd2929dab7",
-  "date": "2019-05-15T17:20:14+08:00",
-  "sha256": "0kcaw0dan3gq7gigymgi96sgn46ibw6mgq5phz24jczn5ghsiai0",
+  "rev": "215ab49ae751301f8d8713c7259da11a5c75458e",
+  "date": "2019-06-12T15:07:48+00:00",
+  "sha256": "0lp8hc86zs4xv2hvwnywxkklc2s4iaqgriqz3vqfd6bcds2shp1m",
   "fetchSubmodules": false
 }
diff --git a/pins/nixpkgs-src.json b/pins/nixpkgs-src.json
index a542a1e..efe7642 100644
--- a/pins/nixpkgs-src.json
+++ b/pins/nixpkgs-src.json
@@ -1,7 +1,7 @@
 {
-  "url": "https://github.com/input-output-hk/nixpkgs",
-  "rev": "c96f5924811f5a8576c9f03d3a630c491fbaf7a3",
-  "date": "2019-05-10T15:32:41+08:00",
-  "sha256": "0iagdz0q37ffkpzyh2f21wjb7x4gx257adlranchzc43460x65c1",
+  "url": "https://github.com/NixOS/nixpkgs",
+  "rev": "61f0936d1cd73760312712615233cd80195a9b47",
+  "date": "2019-05-28T23:19:24-04:00",
+  "sha256": "1fkmp99lxd827km8mk3cqqsfmgzpj0rvaz5hgdmgzzyji70fa2f8",
   "fetchSubmodules": false
 }
diff --git a/release.nix b/release.nix
index 3cb554f..e52090a 100644
--- a/release.nix
+++ b/release.nix
@@ -8,20 +8,14 @@ let
   # cross system settings
   mingwW64 = pkgs.lib.systems.examples.mingwW64;
 
-  # import iohk-nix with the same pin as the nixpkgs above.
-  config = { allowUnfree = false; inHydra = true; allowUnsupportedSystem = true; };
+  leksah-src = pkgs.fetchgit {
+      url = "https://github.com/leksah/leksah";
+      rev = "c179b31ecfa305044a2fd233aace0d48e7aa3a77";
+      sha256 = "19fqr00rg2mx9dpy20brkviz2gfnvamccaln99svbjxmdfyjfklx";
+      fetchSubmodules = true;
+    };
 
-  # linux packages
-  x86_64-linux = importPinned "iohk-nix"
-    { inherit config; nixpkgsJsonOverride = ./pins/nixpkgs-src.json; system = "x86_64-linux"; };
-
-  # macos packages
-  x86_64-macos = importPinned "iohk-nix"
-    { inherit config; nixpkgsJsonOverride = ./pins/nixpkgs-src.json; system = "x86_64-darwin"; };
-
-  # windows cross compiled on linux
-  x86_64-mingw32 = importPinned "iohk-nix"
-    { inherit config; nixpkgsJsonOverride = ./pins/nixpkgs-src.json; system = "x86_64-linux"; crossSystem = mingwW64; };
+  leksah-mingw32 = import leksah-src { system = "x86_64-linux"; crossSystem = mingwW64; };
 
   # jobs contain a key -> value mapping that tells hydra which
   # derivations to build.  There are some predefined helpers in
@@ -30,23 +24,19 @@ let
   #
   # It is however not necessary to use those.
   #
-  jobs = rec {
-    # a very simple job. All it does is call a shell script that print Hello World.
-    hello-world = import ./jobs/trivial-hello-world { inherit pkgs; };
-
-    # this should give us our patched compiler. (e.g. the one
-    # from the pinned nixpkgs set with all the iohk-nix
-    # patches applied.
-
-    # linux
-    ghc864.x86_64-linux = x86_64-linux.pkgs.haskell.compiler.ghc864;
-
-    # macOS
-    ghc864.x86_64-macos = x86_64-macos.pkgs.haskell.compiler.ghc864;
-
-    # linux -> win32
-    # Note: we want to build the cross-compiler. As such we want something from the buildPackages!
-    "${mingwW64.config}-ghc864".x86_64-linux = x86_64-mingw32.pkgs.buildPackages.haskell.compiler.ghc864;
-  };
+  jobs = builtins.mapAttrs (_: args:
+    let leksah = import leksah-src args;
+    in builtins.mapAttrs (_: pkgs.recurseIntoAttrs) {
+      leksah-plan-nix = leksah.pkgs.haskell-nix.withInputs leksah.plan-nix;
+    
+      wrapped-leksah = leksah.wrapped-leksah;
+      leksah-shells = leksah.shells;
+      leksah-haskell-nix-roots = leksah.pkgs.haskell-nix.haskellNixRoots;
+    }) {
+      linux-ghc865 = { system = "x86_64-linux"; haskellCompiler = "ghc865"; };
+      linux-ghc883 = { system = "x86_64-linux"; haskellCompiler = "ghc883"; };
+      macos-ghc865 = { system = "x86_64-darwin"; haskellCompiler = "ghc865"; };
+      macos-ghc883 = { system = "x86_64-darwin"; haskellCompiler = "ghc883"; };
+    };
 in
   jobs