System Design interview practice
Practice system design interview questions for designing scalable, distributed systems. Practice with an AI interviewer that scores clarity, depth, and answer structure — and tells you exactly what to fix.
System Design questions to practice saying out loud
Reading answers isn’t practice. Use these as your warm-up, then run a scored interview and hear yourself answer them.
How do you design a chat application like WhatsApp?
Components: WebSocket servers for real-time messaging, message queue (Kafka) for delivery, database for message persistence (Cassandra for writes, Redis for online status), push notification service, media storage (S3/CDN). Handle delivery receipts, offline queuing, and end-to-end encryption.
What is eventual consistency?
In distributed systems, eventual consistency means all replicas will converge to the same value given enough time without new updates. Trade-off between strong consistency (slower reads) and eventual consistency (faster reads but temporary inconsistency).