Team file sharing
Design a simple file-sharing service for a team. A member uploads a file (up to ~100 MB), gets a shareable link, and other members can download it; some files are private to the uploader and some are shared with the whole team. Storage should be durable and the app server shouldn't be a bottleneck for large transfers. Cover where files live, the data model, and how downloads and access control work.
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.
Clarify4:00 left
Estimate4:00 planned
Design11:30 planned
Deep dive9:30 planned
Failure6:00 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.