Questions by Role
Backend Developer Interview Questions and Answers (2026): APIs, Databases, Scaling and Scenarios
Backend developer and backend engineer interview questions with short answers: HTTP and REST API design, databases (indexes, transactions, isolation levels, SQL vs NoSQL), caching, scaling and system design, concurrency and idempotency, authentication and security (OWASP Top 10:2025), observability, language-specific questions for Node.js, Python and Java, scenario questions, and questions for experienced engineers.