Comment by JakaJancar

Assuming you're fine with keeping the queue in postgres, I've used Procrastinate and it's great:

https://procrastinate.readthedocs.io/en/stable/index.html

Core is not Django-specific, but it has an optional integration. Sync and async, retries/cancellation/etc., very extensible, and IMO super clean architecture and well tested.

IIRC think the codebase is like one-tenth that of Celery.