{ options, config, lib, pkgs, ... }: let inherit (lib.modules) mkIf; cfg = config.modules.desktop.browsers; in { options.modules.desktop.browsers = let inherit (lib.options) mkOption; inherit (lib.types) nullOr str; in { default = mkOption { type = nullOr str; default = null; description = "Default system browser"; example = "firefox"; }; }; config = mkIf (cfg.default != null) { home.sessionVariables.BROWSER = cfg.default; }; }