diff --git a/.envrc b/.envrc
deleted file mode 100644
index 21282b0..0000000
--- a/.envrc
+++ /dev/null
@@ -1,3 +0,0 @@
-#!/usr/bin/env bash
-
-use flake
\ No newline at end of file
diff --git a/.gitignore b/.gitignore
index 73b0670..cce9137 100644
--- a/.gitignore
+++ b/.gitignore
@@ -26,6 +26,5 @@ cabal.project.local~
 # ignore vscodium's local config
 .vscode/
 
-# ignore nix build system
-result*
-.direnv
\ No newline at end of file
+# ignore nix result symlinks
+result*
\ No newline at end of file
diff --git a/Graphics/Engine.hs b/Graphics/Engine.hs
index 3ddab38..5416a90 100644
--- a/Graphics/Engine.hs
+++ b/Graphics/Engine.hs
@@ -44,15 +44,15 @@ processEvent = event noEvent $ \case
   EventMotion {} -> noEvent
   EventResize size -> Event $ Resize size
 
-run :: DisplayableSpace f => (Int, Int) -> f Bool -> SF InputEvent Picture
-run size st =
+run :: forall f. DisplayableSpace f => f Bool -> SF InputEvent Picture
+run st =
   let initSpace = gol' standardRule st
    in proc inp -> do
         let cmdev = processEvent inp
 
         playing <- accumHoldBy (const . not) True -< filterE isPlayPause cmdev
         time <- accum 0.2 -< mapFilterE getChangeSpeed cmdev
-        windowSize <- hold size -< mapFilterE getResize cmdev
+        windowSize <- hold (100, 100) -< mapFilterE getResize cmdev
 
         tick <- tickSignal -< time
         space <- engine initSpace -< gate tick playing
diff --git a/Main.hs b/Main.hs
index 5c166dc..b13cd4c 100644
--- a/Main.hs
+++ b/Main.hs
@@ -6,7 +6,6 @@ import Graphics.Engine (initialSpace, run)
 import Graphics.Gloss
 import Graphics.GlossUtils (playYampa)
 
--- random space just to test things
 space :: ToroidalSpace Bool
 space = tabulate (\(x, y) -> (x + y `mod` 5) * 10 + x - y > 30)
 
@@ -16,4 +15,4 @@ main =
     (InWindow "Conway's Game of Life" (200, 200) (10, 10))
     black
     30
-    (run (200, 200) space)
+    (run space)
\ No newline at end of file
diff --git a/flake.lock b/flake.lock
index b1039cb..e15f5a8 100644
--- a/flake.lock
+++ b/flake.lock
@@ -1,5 +1,21 @@
 {
   "nodes": {
+    "flake-compat": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1627913399,
+        "narHash": "sha256-hY8g6H2KFL8ownSiFeMOjwPC8P0ueXpCVEbxgda3pko=",
+        "owner": "edolstra",
+        "repo": "flake-compat",
+        "rev": "12c64ca55c1014cdc1b16ed5a804aa8576601ff2",
+        "type": "github"
+      },
+      "original": {
+        "owner": "edolstra",
+        "repo": "flake-compat",
+        "type": "github"
+      }
+    },
     "flake-utils": {
       "locked": {
         "lastModified": 1638122382,
@@ -32,6 +48,7 @@
     },
     "root": {
       "inputs": {
+        "flake-compat": "flake-compat",
         "flake-utils": "flake-utils",
         "nixpkgs": "nixpkgs"
       }
diff --git a/flake.nix b/flake.nix
index d57e1bb..9b0d69c 100644
--- a/flake.nix
+++ b/flake.nix
@@ -1,54 +1,59 @@
+# SPDX-FileCopyrightText: 2021 Serokell <https://serokell.io/>
+#
+# SPDX-License-Identifier: CC0-1.0
+
 {
-  description = "Conway's Game of Life in Haskell";
+  description = "My haskell application";
 
   inputs = {
     nixpkgs.url = "github:NixOS/nixpkgs";
     flake-utils.url = "github:numtide/flake-utils";
+
+    flake-compat.url = "github:edolstra/flake-compat";
+    flake-compat.flake = false;
   };
 
   outputs = { self, nixpkgs, flake-utils, ... }:
     flake-utils.lib.eachDefaultSystem (system:
       let
-        overlays = [ ];
         pkgs = nixpkgs.legacyPackages.${system};
+
+        haskellPackages = pkgs.haskellPackages;
+
+        jailbreakUnbreak = pkg:
+          pkgs.haskell.lib.doJailbreak (pkg.overrideAttrs (_: { meta = { }; }));
+
+        packageName = "conways-game-of-life";
+
         execName = "gol";
-        hp = pkgs.haskellPackages; # pkgs.haskell.packages.ghc921;
-        project = returnShellEnv:
-          hp.developPackage {
-            inherit returnShellEnv;
-            name = "conways-game-of-life";
-            root = ./.;
-            withHoogle = false;
-            overrides = self: super: with pkgs.haskell.lib; {
-              # Use callCabal2nix to override Haskell dependencies here
-              # cf. https://tek.brick.do/K3VXJd8mEKO7
-              # Example: 
-              # > NanoID = self.callCabal2nix "NanoID" inputs.NanoID { };
-              # Assumes that you have the 'NanoID' flake input defined.
-            };
-            modifier = drv:
-              pkgs.haskell.lib.addBuildTools drv (with hp; [
-                # Specify your build/dev dependencies here. 
-                hlint
-                haskell-language-server
-                ormolu
-
-                pkgs.mesa
-                pkgs.mesa_glu
-                pkgs.freeglut
-              ]);
+      in {
+        packages.${packageName} =
+          haskellPackages.callCabal2nix packageName self rec {
+            # Dependency overrides go here
           };
-      in
-      {
-        # Used by `nix build` & `nix run` (prod exe)
-        defaultPackage = project false;
 
-        defaultApp = {
+        defaultPackage = self.packages.${system}.${packageName};
+
+        apps.${execName} = {
           type = "app";
-          program = "${self.defaultPackage.${system}}/bin/${execName}";
+          program = "${self.packages.${system}.${packageName}}/bin/${execName}";
         };
 
-        # Used by `nix develop` (dev shell)
-        devShell = project true;
+        defaultApp = self.apps.${system}.${execName};
+
+        devShell = pkgs.mkShell {
+          buildInputs = with haskellPackages; [
+            ghcid
+            cabal-install
+            hlint
+            pkgs.haskell-language-server
+            pkgs.ormolu
+
+            pkgs.mesa
+            pkgs.mesa_glu
+            pkgs.freeglut
+          ];
+          inputsFrom = builtins.attrValues self.packages.${system};
+        };
       });
-}
+}
\ No newline at end of file
diff --git a/shell.nix b/shell.nix
new file mode 100644
index 0000000..81e3286
--- /dev/null
+++ b/shell.nix
@@ -0,0 +1,8 @@
+(import (
+  let lock = builtins.fromJSON (builtins.readFile ./flake.lock);
+  in
+  fetchTarball {
+    url = "https://github.com/edolstra/flake-compat/archive/${lock.nodes.flake-compat.locked.rev}.tar.gz";
+    sha256 = lock.nodes.flake-compat.locked.narHash;
+  }
+) { src = ./.; }).shellNix
\ No newline at end of file