Mid-level interview questionAsked at Figma · interview write-up
Design a personalized feed ranker and a natural-language-to-HTML generation system. Cover objectives, cold start, exploration and evaluation for each.
Model answer
Feed: optimize meaningful engagement, like opens and remixes, checked against retention. Retrieve, then rank; cold-start users get content embeddings and popular-by-segment items, plus a small exploration slot run as a bandit. Evaluate offline with NDCG, then A/B.
HTML: an LLM with design-system components in context and constrained output. Check that the output parses and renders, then compare rendered screenshots against references with a calibrated judge. Online, track how often users keep the result.
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