General Backend Developer interview prep
1 live role at PeopleboxAPIs, databases, concurrency and system design — the server-side engineering interview across product companies and fintech.
Typical Backend Developer interview rounds
- 1 DSA round. Coding problems plus complexity analysis.
- 2 Language & runtime. Deep dive on your primary language (Java/Node/Python/Go) and its concurrency model.
- 3 Database & API design. Schema design, indexing, transactions and REST/gRPC API design.
- 4 System design. Designing scalable, fault-tolerant backend services.
Commonly-asked Backend Developer questions
- Explain the difference between SQL and NoSQL, and when you'd choose each.
- What is database indexing and how does it speed up queries?
- Explain ACID properties in a database transaction.
- What is the difference between REST and GraphQL?
- How do you handle concurrency and race conditions in your backend?
- What is a deadlock and how do you prevent it?
- Explain caching strategies — write-through, write-back and cache invalidation.
- What is the difference between horizontal and vertical scaling?