Mid-level interview questionAsked at Mercor · interview write-up
Design and build a candidate search system that ranks people from noisy profiles and free-text queries while enforcing hard criteria.
Model answer
Separate hard filters from soft ranking. Parse profiles and the query into structured fields, like location, experience and skills, with an LLM extractor plus rules, and apply hard criteria as filters so no ranking can break them. Retrieve with hybrid search over profile text, then rank on skill match, seniority and recency. Show why each person matched. Evaluate on recruiter-labelled queries with NDCG, and count hard-criteria violations, which must be zero.
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