What should I say in a design interview?

5. Discuss Trade-Offs

• Show you understand the implications of your choices.
• Example: "Using strong consistency ensures accuracy but might increase latency. However, for this application, eventual consistency might be acceptable."

6. Address Non-Functional Requirements

• Cover aspects like:
  • Scalability: "We can add servers behind the load balancer to handle traffic spikes."
  • Fault Tolerance: "Replica databases ensure data availability even if one fails."
  • Security: "Encrypt sensitive data in transit and at rest."
  • Performance: "Caching and CDN integration reduce response time for global users."

7. Handle Edge Cases

• Show you’ve thought of potential failures or unusual scenarios.
• Example: "What happens if the database goes down? We’ll have a fallback to serve cached data temporarily."

8. Iterate and Optimize

• Once the basic design is complete, discuss improvements.
• Example:
  • "We could implement rate limiting to prevent abuse."
  • "Using a CDN for static content can further reduce latency."

9. Engage in Discussion

• Treat the interview like a collaborative problem-solving session.
• Example: "Do you think a graph database might be more effective for this use case?"

10. Summarize Your Design

• End by recapping your design choices, why they were made, and how they meet the requirements.
• Example: "This design ensures scalability with sharding, reliability through database replication, and performance with caching."

Additional Tips

• Stay calm and organized, even if faced with challenging questions.
• Communicate your thought process clearly at every step.
• Use diagrams or sketches if possible to make your explanation visual.

By focusing on these elements, you’ll effectively convey your design skills, technical knowledge, and problem-solving abilities in the interview.