Multi-region read scaling
Design read-scaling for a multi-tenant SaaS app (project management) where the primary DB is in us-east but 40% of users are in Europe and complain about slow page loads. You want to serve European reads locally from replicas while keeping correctness: a user who just saved a task must see it on the next page load, and dashboards can tolerate a few seconds of staleness. How do you architect the replica topology and routing?
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.