move things out of default.nix

modules/nix.nix

@@ -0,0 +1,55 @@
+{ lib, pkgs, inputs, config, ... }:
+{
+  environment.variables = {
+    NIXPKGS_ALLOW_UNFREE = "1";
+  };
+
+  nixpkgs.flake.setNixPath = true;
+  nixpkgs.flake.setFlakeRegistry = true;
+
+  nix = {
+    package = pkgs.nixVersions.latest;
+
+
+    settings = {
+      experimental-features = [ "nix-command" "flakes" ];
+
+      auto-optimise-store = true;
+
+      keep-outputs = true;
+      keep-derivations = true;
+
+      substituters = [
+        "https://nix-community.cachix.org"
+        "https://nixpkgs-wayland.cachix.org"
+        "https://wezterm.cachix.org"
+        "https://niri.cachix.org"
+        "https://cache.soopy.moe"
+      ];
+      trusted-public-keys = [
+        "nix-community.cachix.org-1:mB9FSh9qf2dCimDSUo8Zy7bkq5CX+/rkCWyvRCYg3Fs="
+        "nixpkgs-wayland.cachix.org-1:3lwxaILxMRkVhehr5StQprHdEo4IrE8sRho9R9HOLYA="
+        "wezterm.cachix.org-1:kAbhjYUC9qvblTE+s7S+kl5XM1zVa4skO+E/1IDWdH0="
+        "niri.cachix.org-1:Wv0OmO7PsuocRKzfDoJ3mulSl7Z6oezYhGhR+3W2964="
+        "cache.soopy.moe-1:0RZVsQeR+GOh0VQI9rvnHz55nVXkFardDqfm4+afjPo="
+      ];
+    };
+  };
+
+  nix.optimise.automatic = true;
+  nix.gc = {
+    automatic = true;
+    dates = "weekly";
+    options = "--delete-older-than 14d";
+  };
+
+  programs.command-not-found.enable = false;
+  programs.nix-index.enable = true;
+
+  # compat w/ non-nix programs
+  programs.nix-ld.enable = true;
+  programs.appimage = {
+    enable = true;
+    binfmt = true;
+  };
+}

modules/xdg.nix

@@ -1,4 +1,4 @@
-{ ... }:
+{ pkgs, ... }:
 {
   config = {
     hm.xdg.enable = true;
@@ -19,5 +19,9 @@
         screenshots = "${pictures}/screenshots";
       };
     };
+
+    environment.systemPackages = with pkgs; [
+      xdg-utils
+    ];
   };
 }