- Difficulty
- Intermediate → advanced
- Time
- 75–100 min
Make work executable
Describe the worker-loop change you would implement, define its state transitions, and explain how you would test success, failure, and completion.
What to demonstrate: Can you make implicit state transitions explicit?
Handle transient failure
Add bounded retries and backoff without blocking unrelated work.
What to demonstrate: Can you separate retryable from terminal failure?
Make delivery safe
Protect downstream systems when jobs are delivered more than once.
What to demonstrate: Can you reason honestly about at-least-once execution?
Recover after restart
Replace volatile assumptions with a durable state and lease model.
What to demonstrate: Can you preserve correctness across process boundaries?