feat: refactor, hyprland - greet with autologin

modules/base.nix

@@ -0,0 +1,53 @@
+{
+  pkgs,
+  lib,
+  username,
+  ...
+}: {
+  nix.settings = {
+    # enable flakes globally
+    experimental-features = ["nix-command" "flakes"];
+
+    # given the users in this list the right to specify additional substituters via:
+    #    1. `nixConfig.substituers` in `flake.nix`
+    #    2. command line args `--options substituers http://xxx`
+    trusted-users = [username];
+
+    substituters = [
+      # cache mirror located in China
+      # status: https://mirror.sjtu.edu.cn/
+      "https://mirror.sjtu.edu.cn/nix-channels/store"
+      # status: https://mirrors.ustc.edu.cn/status/
+      # "https://mirrors.ustc.edu.cn/nix-channels/store"
+
+      "https://cache.nixos.org"
+    ];
+
+    trusted-public-keys = [
+      "cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY="
+    ];
+    builders-use-substitutes = true;
+  };
+
+  # do garbage collection weekly to keep disk usage low
+  nix.gc =
+    {
+      automatic = lib.mkDefault true;
+      options = lib.mkDefault "--delete-older-than 7d";
+    }
+    // (
+      if pkgs.stdenv.isLinux
+      then {
+        dates = lib.mkDefault "weekly";
+      }
+      else {
+        # nix-darwin
+        interval = {
+          Hour = 24;
+        };
+      }
+    );
+
+  # Allow unfree packages
+  nixpkgs.config.allowUnfree = lib.mkDefault false;
+}