Add overlays.nix

Author: staticdev

flake.nix

@@ -30,6 +30,7 @@
           ./configuration.nix
           ./modules/sysconf.nix
           inputs.home-manager.nixosModules.default
+          (import "${self}/pkgs/overlays.nix" { inherit inputs; })
         ]
         ++ prop.modules;
       };

pkgs/overlays.nix

@@ -0,0 +1,16 @@
+{ inputs, ... }:
+let
+  pkgs-unstable = _: prev: {
+    pkgs-unstable = import (inputs.nixpkgs-unstable) {
+      inherit (prev.stdenv) system;
+    };
+  };
+in
+{
+  nix.nixPath = [ "nixpkgs=${inputs.nixpkgs}" ];
+  nixpkgs = {
+    overlays = [
+      pkgs-unstable
+    ];
+  };
+}