Queues & Background Workers

Queues, publish/subscribe, and the log as a primitive. Delivery semantics, idempotency and ordering, then the architectures they make possible — and the debugging they cost you.

This module is 04.1 of the 5 in Messaging & Event Streams. It runs about 4 hours across 5 lessons, and closes with Backlog — A queue is two hours behind and growing. Drain it without dropping work or melting the database.