Add unstable overlay

flake.nix

@@ -4,33 +4,43 @@
   inputs = {
     # nixpkgs.url = "github:nixos/nixpkgs?ref=nixos-unstable";
     nixpkgs.url = "github:nixos/nixpkgs?ref=nixos-23.11";
+    nixpkgs-unstable.url = "github:nixos/nixpkgs?ref=nixos-unstable";
     home-manager = {
       url = "github:nix-community/home-manager?ref=release-23.11";
       inputs.nixpkgs.follows = "nixpkgs";
     };
   };
 
-  outputs = { self, nixpkgs, ... }@inputs:
+  outputs = { self, nixpkgs, nixpkgs-unstable, ... }@inputs:
     let
       system = "x86_64-linux";
       user = "torjus";
+      overlay-unstable = final: prev: {
+        unstable = import nixpkgs-unstable {
+          inherit system;
+          config.allowUnfree = true;
+        };
+      };
     in
     {
       nixosConfigurations = {
         prismo = nixpkgs.lib.nixosSystem {
-          system = "x86_64-linux";
+          inherit system;
           specialArgs = { inherit inputs self user; };
           modules = [ ./hosts/prismo ];
         };
         magicman = nixpkgs.lib.nixosSystem {
-          system = "x86_64-linux";
+          inherit system;
           specialArgs = { inherit inputs self user; };
           modules = [ ./hosts/magicman ];
         };
         gunter = nixpkgs.lib.nixosSystem {
-          system = "x86_64-linux";
+          inherit system;
           specialArgs = { inherit inputs self user; };
-          modules = [ ./hosts/gunter ];
+          modules = [
+            ({ config, pkgs, ... }: { nixpkgs.overlays = [ overlay-unstable ]; })
+            ./hosts/gunter
+          ];
         };
       };
     };