✨ Add tons of missing system, desktop and home modules

modules/nixos/system/nix/default.nix

@@ -0,0 +1,50 @@
+{
+  lib,
+  pkgs,
+  self,
+  config,
+  ...
+}: let
+  inherit (lib) mkEnableOption mkIf;
+  inherit (self) namespace;
+
+  cfg = config.${namespace}.system.nix;
+in {
+  options.${namespace}.system.nix = {
+    enable = mkEnableOption "Nix configuration overrides.";
+    use-lix = mkEnableOption "Lix as an alternative to CppNix.";
+    use-nixld = mkEnableOption "the use of dynamically linked executables on nix based systems.";
+  };
+
+  config = mkIf cfg.enable {
+    nix = {
+      settings = {
+        auto-optimise-store = true;
+        builders-use-substitutes = true;
+        experimental-features = ["nix-command" "flakes"];
+        keep-derivations = true;
+        keep-outputs = true;
+        max-jobs = "auto";
+        warn-dirty = false;
+      };
+
+      # Garbage collection configuration.
+      gc = {
+        automatic = true;
+        dates = "daily";
+        options = "--delete-older-than 3d";
+      };
+
+      package = mkIf cfg.use-lix pkgs.lix; # Enable LIX
+    };
+
+    # Dynamic libraries for unpackaged programs
+    programs.nix-ld = mkIf cfg.use-nixld {
+      enable = true;
+      libraries = with pkgs; [
+        glibc
+        libcxx
+      ];
+    };
+  };
+}