-record(flow_storage, {
    save :: fun((telega@flow@types:flow_instance()) -> {ok, nil} |
        {error, any()}),
    load :: fun((binary()) -> {ok,
            gleam@option:option(telega@flow@types:flow_instance())} |
        {error, any()}),
    delete :: fun((binary()) -> {ok, nil} | {error, any()}),
    list_by_user :: fun((integer(), integer()) -> {ok,
            list(telega@flow@types:flow_instance())} |
        {error, any()})
}).