Laravel路由中使用defer触发PHP致命错误求助

我正在Laravel里折腾defer功能，写了下面这段路由代码：

Route::get('testing', function () {
    defer(function(){
        //          sleep(3);
        Log::info('sleeping');
    })
        ->always(); // Will always run defer once executed

    return 'Rtoufasdfa';
});

结果运行后，我的Sail终端里弹出了这个PHP致命错误：

PHP Fatal error:  Uncaught Swoole\Error: API must be called in the coroutine in /var/www/html/routes/web.php:94
  Stack trace:
2024-11-08 23:15:05,688 INFO reaped unknown pid 1093 (exit status 255)
 2024-11-08 23:15:05,688 INFO reaped unknown pid 1094 (exit status 255)
 #0 /var/www/html/routes/web.php(94): defer()

有没有熟悉defer用法的朋友碰到过这个问题呀？

备注：内容来源于stack exchange，提问作者gerl