{ config, lib, pkgs, ... }: let cfg = config.programs.foo; settingsFormat = pkgs.format.json { }; in { options.programs.foo = { enable = lib.mkEnableOption "foo, a sample program"; package = lib.mkPackageOption pkgs "foo" { }; settings = lib.mkOption { type = settingsFormat.type; default = { }; # TODO: Don't forget to set an example here. description = '' The settings of the program. ''; }; }; }