Backend Engineer Interview Prep
Backend engineers build server-side logic, APIs, and data pipelines. Interviews cover system design, databases, scalability, and coding proficiency.
Practice This Interview with AI — FreeKey Skills to Highlight
Common Behavioral Questions
Tell me about a time you designed a system that needed to scale significantly.
Describe a production incident you resolved. What was your debugging process?
How do you approach API design for maintainability?
Tell me about a time you improved the reliability of a backend system.
How do you balance building new features with maintaining existing systems?
Role-Specific Questions
Design a rate-limiting system for an API.
How would you handle database migrations with zero downtime?
Explain the CAP theorem and its implications for distributed systems.
How do you approach caching? When would you use Redis vs. CDN?
Design an event-driven architecture for an e-commerce order processing system.
Interview Tips
Draw diagrams during system design — show data flow clearly
Discuss trade-offs explicitly (consistency vs. availability, latency vs. throughput)
Be ready to estimate system capacity (QPS, storage, bandwidth)
Know your databases well — indexing, query optimization, sharding
Prepare examples of systems you've built and the decisions you made
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