Kuo delivered a well-structured presentation with impressive breadth, systematically addressing all requirements while exploring technical implications in depth. He excelled at articulating trade-offs, thoughtfully weighing competing factors like performance versus complexity and short-term costs against long-term maintainability, demonstrating mature engineering judgment.

Areas of Strength

• Enumerated all functional and non-functional requirements clearly
• Proactively identified challenges of double booking
• Proactively identified challenges of matching logics and status change
• Proactively addressed fault tolerance mechanisms and retry policy design
• Proactively drove deep-dive technical discussions

Areas for Improvement

• Clearly justify each major design decision, Don’t just say “I’ll use Kafka for message delivery.” — explain why.

“I chose Kafka because it supports high-throughput event streaming, ensures durability through replication, and enables independent scaling between producers and consumers. Alternatives like RabbitMQ or SQS would simplify setup but trade off on ordering guarantees and throughput.”
Show that each design choice reflects trade-off awareness and alignment with system goals (e.g., latency, cost, fault tolerance).

• Keep the interviewer engaged
  Treat the interview as a collaborative discussion, not a monologue.
  For example:

• “Would you like me to go deeper into the storage design or focus on how the scheduler handles retries?”
• “Is it okay if I add some diagrams to clarify the control flow?”
• Frequent check-ins like this signal strong communication and adaptability—key traits at the senior/staff level.

• Dive deeper into technical details when explaining technologies. Instead of saying “We’ll use Redis for caching,” go deeper:

“We’ll use Redis with TTL-based eviction for frequently accessed metadata. The cache hit rate should reach 90%+, reducing DB load significantly. ”
Discuss internals, limitations, and scaling implications—this shows depth and practical experience, not just surface-level familiarity.

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