Typo-tolerant autocomplete
Design typo-tolerant autocomplete that still returns good suggestions when the user mistypes the prefix — 'restaraunt', 'bluetooth', 'iphine' — within a 50ms p99 budget at 500k QPS. Exact-prefix trie matching returns nothing for a typo. You can't run full edit-distance against millions of terms per keystroke. How do you make fuzzy matching fast enough to stay on the autocomplete hot path?
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.
Clarify4:30 left
Estimate4:30 planned
Design13:30 planned
Deep dive10:30 planned
Failure7:00 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.