Webhook delivery queue isolation
Design the ingress queueing and shaping for a webhook-delivery system that must deliver events to thousands of customer endpoints with wildly different processing speeds — some endpoints respond in 50ms, others in 10s, and some are down for hours. A naive shared queue lets slow/dead endpoints clog delivery for fast ones (head-of-line blocking across customers). Design the queueing model, per-endpoint shaping and backoff, how you isolate slow consumers, and how you bound memory/queue growth when an endpoint is down for a long time.
What a strong answer looks like
Clarify scale and constraints first. Propose a clean component breakdown, then go deep on the hard parts (data model, bottlenecks, consistency, failure modes) and name the trade-offs you are making.
Clarify5:00 left
Estimate5:00 planned
Design15:00 planned
Deep dive12:00 planned
Failure8:00 planned
Which questions mattered is sealed until you submit. Telling you now would just be handing over the edge cases.
Run or narrate your approach, then ask the coach.