Why "just do it in the request" stops working, and what the alternative looks like.
Background Jobs and Schedules
Work that outlives the request that started it: queues, workers, and cron.
Some work cannot happen while a user waits. This course covers how apps hand work to themselves, why scheduled jobs are harder than they look, and the retry bug that charges a customer twice.
Start the first lesson0/4 lessons read
By the end you can
- Recognise which work must be moved out of the request
- Explain queues and workers without hand-waving
- Reason about cron jobs, including the ways they silently fail
- Understand idempotency and why retries need it
Lessons
A list of things to do, and processes that pull from it. That is genuinely all it is.
Work that happens because of the clock, and the four ways it quietly fails.
The bug where a customer is billed twice, and the one idea that prevents it.