add wallpapers, using git-lfs to manage it

home/david/modules/wallpaper/default.nix

@@ -0,0 +1,22 @@
+{ lib, config, ... }:
+let
+  cfg = config.david.wallpaper;
+in
+{
+  options = {
+    david.wallpaper = {
+      enable = lib.mkOption {
+        type = lib.types.bool;
+        default = true;
+        example = false;
+      };
+    };
+  };
+  config = lib.mkIf cfg.enable {
+    home.file."wallpaper" = {
+      force = true;
+      recursive = true;
+      source = ./pic;
+    };
+  };
+}