let's hope this doesn't break everything :3

modules/applications/firefox.nix

@@ -0,0 +1,17 @@
+{ lib, config, pkgs, ... }:
+let 
+	cfg = config.modules.apps.firefox;
+in
+{
+	options.modules.apps.firefox = {
+		enable = lib.mkEnableOption "enable firefox";
+	};
+
+	config = lib.mkIf cfg.enable {
+		programs.firefox = {
+			enable = true;
+			# TODO: add some default firefox settings
+		};
+	};
+
+}