Coroutines
Coroutines are fairly similar to crons. However, cron as meant to be run in the background, while coroutines are meant to be run in the foreground. This means it's important to not run blocking code in coroutines.
In case you're not sure whether to use coroutines or crons, it's recommended to use a cron.
Coroutines are implemented by implementing the Swift\Coroutine\CoroutineInterface
interface.