Is there a service for scheduling tasks, schedules with an open API?

Question

JavaScript

Is there a service for scheduling tasks, scheduling and all that?
Yes, I know that it exists, but it needs an open API so that I myself can write my own rules, types of tasks, etc. for it.
The scheduler is a complicated thing and some standard functions are often missing.

You don't want to write everything from scratch.

spoiler

Или может есть хороший проект планировщика с открытым кодом с уже реализованными базовыми функциями?

Answer 1

Google Calendar API