The 60-second answer
Define the objective and constraints first: useful connection formation, privacy/safety, latency, and avoiding spammy recommendations. Generate candidates from graph proximity, shared context, contacts/groups, and embedding retrieval; apply eligibility/privacy filters before ranking.
Build the answer in this order
Define the objective and constraints first: useful connection formation, privacy/safety, latency, and avoiding spammy recommendations.
Generate candidates from graph proximity, shared context, contacts/groups, and embedding retrieval; apply eligibility/privacy filters before ranking.
Rank with graph, profile, interaction, and freshness features while correcting for exposure bias and cold-start users.
Evaluate candidate recall plus ranking quality, connection acceptance/quality, hides/reports, diversity, and long-term network health.
A useful interview mental model
This is the shape of a strong answer—not a script to memorize.
Senior-level signal
- Senior answers discuss graph leakage, feedback loops, privacy boundaries, and exploration for sparse users.
- Separate candidate-generation recall from ranker quality and design safe fallbacks when online features are stale.
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.