I started with the broker and worked outward, which felt right at the time but I think I should've anchored on the use case first.
Start by clarifying functional and non-functional requirements, then sketch a high-level architecture with core components like producers, brokers, and consumers. Dive into key design decisions such as delivery guarantees, scalability, and fault tolerance, and discuss trade-offs between different approaches.
Pro tip: Explicitly state your assumptions and prioritize requirements early; this shows you can navigate ambiguity and focus on what matters most for the system's success.
Ask questions to understand the scale, latency, durability, and ordering requirements, as well as the expected number of topics and subscribers.
Outline the main components: producers, brokers, consumers, and a coordination service (e.g., ZooKeeper). Describe how messages flow from producers to consumers via topics.
Detail the broker's role in message storage, replication, and delivery. Discuss partitioning for scalability and consumer groups for parallel processing.
Explain how to handle message ordering, delivery guarantees (at-least-once, at-most-once, exactly-once), and fault tolerance (replication, leader election).
Compare design choices (e.g., pull vs. push, storage options) and explain how the system scales horizontally and handles failures.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.