Implement Work Queue with Timeout, Retries, and Dead Letter Queue

Problem Overview

Implement a fault-tolerant work queue, WorkQueue. The reports describe the queue and then a dependency follow-up that has to be coded, so it is laid out here as two parts. One report gives 60 minutes for it in a phone screen and calls the delivery guarantee at-least-once. Another says no…

• 1 candidate-reported follow-up — the exact probes interviewers asked, with the trigger for each
• The rest of the problem statement — full requirements, constraints, and edge cases
• Approach and trade-offs — what passing candidates did, and the mistakes that sink people