Candidates commonly report a scale-first round. Expect very large numbers from the opening sentence, and be ready to justify a data structure choice in more detail than many rounds ask for. Interviewers often go deep on one subproblem rather than broad across the system.
Numbers and Design weigh heaviest. Vague estimates cost you.
Closest interviewer archetype: The Scale Breaker — Multiplies your traffic, adds celebrity users and hot keys, kills a region.
Questions
Design search autocomplete
hardDesign the suggestions that appear as a user types into a search box. Assume global traffic and that suggestions come from what people have searched for before.
5 hints available · try it →Design a web crawler
hardDesign a system that crawls the web: fetches pages, extracts links, and keeps going. Assume you want to crawl billions of pages and keep them reasonably fresh.
5 hints available · try it →