Add binary cache support

system/default.nix

@@ -4,8 +4,8 @@ _: {
     ./boot
     ./services
     ./programs
+    ./nix
     ./system.nix
-    ./nix.nix
     ./network.nix
     ./localisation.nix
   ];

system/nix/cachix.nix

@@ -0,0 +1,25 @@
+_: {
+  nix.settings = {
+    # Set up various binary cache providers, compiling everything is too slow and annoying
+    # these will be used on all machines, but there's really no reason not to include all
+    # providers, even if we won't pull some of the packages these cache
+    substituters = [
+      "https://cache.nixos.org"
+      "https://nix-community.cachix.org" # nix-community flake
+      "https://nixpkgs-unfree.cachix.org" # unfree-package cache
+      "https://numtide.cachix.org" # another unfree package cache
+      "https://nixpkgs-wayland.cachix.org" # automated builds of *some* wayland packages
+      "https://hyprland.cachix.org" # hyprland
+      "https://ags.cachix.org" # ags
+    ];
+    trusted-public-keys = [
+      "cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY="
+      "nix-community.cachix.org-1:mB9FSh9qf2dCimDSUo8Zy7bkq5CX+/rkCWyvRCYg3Fs="
+      "nixpkgs-unfree.cachix.org-1:hqvoInulhbV4nJ9yJOEr+4wxhDV4xq2d1DK7S6Nj6rs="
+      "numtide.cachix.org-1:2ps1kLBUWjxIneOy1Ik6cQjb41X0iXVXeHigGmycPPE="
+      "nixpkgs-wayland.cachix.org-1:3lwxaILxMRkVhehr5StQprHdEo4IrE8sRho9R9HOLYA="
+      "hyprland.cachix.org-1:a7pgxzMz7+chwVL3/pzj6jIBMioiJM7ypFP8PwtkuGc="
+      "ags.cachix.org-1:naAvMrz0CuYqeyGNyLgE010iUiuf/qx6kYrUv3NwAJ8="
+    ];
+  };
+}

system/nix/default.nix

@@ -1,5 +1,10 @@
 { pkgs, ... }:
 {
+
+  imports = [
+    ./cachix.nix
+  ];
+
   system.autoUpgrade.enable = false;
 
   nix = {
@@ -39,3 +44,4 @@
   # Git is needed for flakes
   environment.systemPackages = [ pkgs.git ];
 }
+