System Design
Consistency & CAP
6 practice questions. Free questions open a full answer guide; the rest unlock with Pro.
- Design the backend for a real-time collaborative document editor (like Google Docs). Focus on conflict resolution and consistency.
- You're designing a globally-distributed shopping cart and an order-ledger service. For each, would you favor strong consistency or availability, and why?Go Pro
- How do you decide where a system should sit on the consistency spectrum, and why do you think CAP is the wrong frame for that decision in practice?Go Pro
- Through the lens of CAP, how do you decide whether a service should favor consistency or availability during a network partition? Make it concrete with two services that should land on opposite sides.Go Pro
- You inherit an eventually consistent multi-master store where two regions can accept writes to the same key. How do you handle the resulting write conflicts, and what would push you toward CRDTs versus last-writer-wins?Go Pro
- A teammate proposes serving user reads from an eventually-consistent replica to cut latency, but users keep reporting they can't see edits they just made. How would you diagnose and fix this?Go Pro
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