The 60-second answer
Define discovery goals beyond clicks: saves, long-term satisfaction, diversity, novelty, safety, and creator/ecosystem health. Generate candidates from graph/co-engagement, visual/text embeddings, boards/topics, followed creators, trending, and exploration sources.
Build the answer in this order
Define discovery goals beyond clicks: saves, long-term satisfaction, diversity, novelty, safety, and creator/ecosystem health.
Generate candidates from graph/co-engagement, visual/text embeddings, boards/topics, followed creators, trending, and exploration sources.
Rank with user/item/context features plus multimodal content representations, correcting for exposure/popularity feedback loops.
Evaluate retrieval recall, ranking quality, saves, session/long-term outcomes, diversity, tail coverage, latency, and negative feedback.
A useful interview mental model
This is the shape of a strong answer—not a script to memorize.
Senior-level signal
- Senior answers discuss visual/content cold start and exploration for new pins/creators.
- Include multi-objective slate construction so diversity and ecosystem constraints are not bolted on after ranking.
What the interviewer is really testing
Likely follow-up questions
Common weak-answer patterns
- Jumping to a model before defining the product contract.
- Listing components without bottlenecks, metrics, or failure handling.
- Ignoring data quality, serving latency, monitoring, and iteration.