Sponsored search ranking
Design the ranking system for sponsored-product results in an e-commerce search results page. The system must blend organic relevance with paid ads, run a real-time auction (advertisers bid per click), maximize a mix of revenue and user relevance, and stay under 80ms of added latency. Sellers can run thousands of campaigns; budgets must not overspend.
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.
Clarify6:00 left
Estimate6:00 planned
Design18:30 planned
Deep dive14:30 planned
Failure10:00 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.