System design interview question
"Design a distributed message queue like Kafka. Producers write messages to topics, consumers read them, messages are durable and replayable, and it must handle millions of messages per second. Tell me how you achieve that throughput and what delivery guarantees you offer."
the log abstraction and why it is fast, plus replication and consumer-group semantics. The distinguishing insight is that treating the queue as an append-only log rather than a mutable collection of messages is what enables sequential I/O, zero-copy transfer, and replay — three properties a traditional queue cannot offer simultaneously.
On Practick another engineer interviews you live for 60 minutes on a question from this bank. They have the full interviewer guide beside the call: the answers to your clarifying questions, the numbers to hand out, a ladder of follow-ups and a scoring rubric. You get the model solution once the session settles. It is free: interview someone for an hour and you have earned your own.
Book a free mock interviewAll 132 system design interview questions
System design mock interviews · DSA interview questions · Free mock interview practice · Browse interviewers · Sign in