Flake-enable the project

shell.nix

@@ -1,28 +1,9 @@
-let
-  nixpkgs = builtins.fetchTarball {
-    url    = "https://github.com/NixOS/nixpkgs/archive/87d9c84817d7be81850c07e8f6a362b1dfc30feb.tar.gz";
-    sha256 = "0pcasnmdbs2lrsp4m8ww06xd7b318agfygi61qjsizb328nxhcqa";
-  };
-
-  overlay = pkgsNew: pkgsOld: {
-    haskellPackages = pkgsOld.haskellPackages.override (old: {
-      overrides =
-        pkgsNew.lib.composeExtensions
-          (old.overrides or (_: _: { }))
-          (haskellPackagesNew: haskellPackagesOld: {
-            nix-serve-ng =
-              pkgsNew.haskell.lib.overrideCabal
-                (haskellPackagesNew.callPackage ./nix/nix-serve-ng.nix { })
-                (old: {
-                  executableSystemDepends = (old.executableSystemDepends or []) ++ [
-                    pkgsNew.boost.dev
-                  ];
-                });
-          });
-    });
-  };
-
-  pkgs = import nixpkgs { config = { }; overlays = [ overlay ]; };
-
-in
-  pkgs.haskellPackages.nix-serve-ng.env
+(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