overlays: Import the simple overlay

lib/mkSystem.nix

@@ -41,6 +41,7 @@ in inputs.nixpkgs.lib.nixosSystem {
         nur.overlay
         emacs.overlay
         (import ../packages)
+        (import ../overlays/simple.nix)
       ];
     }
 

overlays/default.nix

@@ -1,16 +1,6 @@
-{
+{ pkgs }:
-  pkgs
-, lib
-}:
 
 {
-  emacs = import (builtins.fetchGit {
-    url = "https://github.com/nix-community/emacs-overlay.git";
-    ref = "master";
-    rev = "ce0e9482d53d69bedc8416d8a984d00e17607826";
-  });
-  nur = import ./nur.nix pkgs;
-  custom = import ../packages;
   simple = import ./simple.nix;
   surface = import ./surface.nix pkgs;
 }

overlays/nur.nix

@@ -1,10 +0,0 @@
-pkgs: final: prev:
-
-{
-  nur = import (builtins.fetchTarball {
-    url = "https://github.com/nix-community/NUR/archive/master.tar.gz";
-    sha256 = "0fz7zdfvjfjzg46w7khvwr5jhpd9w8yx0cdd9gnmbkzxhbspbmwq";
-  }) {
-    inherit pkgs;
-  };
-}

overlays/surface.nix

@@ -1,8 +1,8 @@
-pkgs: final: prev:
+final: prev:
 
 let
   libwacomPatchesCommit = "f811946d7d8bacb3b9ee75f08c150c435ad59331";
-  mkPatch = name: sha256: pkgs.fetchpatch {
+  mkPatch = name: sha256: prev.fetchpatch {
     name = "${name}.patch";
     url = "https://raw.githubusercontent.com/linux-surface/libwacom-surface/${libwacomPatchesCommit}/${name}.patch";
     sha256 = sha256;