Backend Developer Interview Guide: APIs, Databases, and Architecture
Complete guide to backend developer interviews covering API design, database optimization, microservices architecture, and server-side performance.
Backend developer interviews evaluate your ability to design and build server-side systems that are scalable, secure, and performant. Whether you work with Node.js, Python, Java, or Go, the core concepts tested are remarkably consistent across technology stacks.
API design is a central topic in backend interviews. Understand RESTful principles including resource naming, HTTP methods, status codes, and versioning. Be familiar with GraphQL as an alternative and know when each approach is appropriate. Practice designing APIs that are intuitive, consistent, and well-documented.
Database knowledge is critical. Be prepared to discuss relational database design including normalization, indexing strategies, and query optimization. Understand NoSQL databases and when they are appropriate. Know how to handle database migrations, replication, and sharding for scalability.
Authentication and authorization are commonly tested topics. Understand OAuth 2.0, JWT tokens, session management, and role-based access control. Be ready to discuss how you secure APIs against common vulnerabilities including SQL injection, cross-site scripting, and cross-site request forgery.
Microservices architecture questions are increasingly common for senior roles. Understand the trade-offs between monolithic and microservice architectures, service communication patterns like REST and message queues, service discovery, and distributed transaction management.
Use HireFlow to practice explaining your backend architecture decisions and trade-offs. The ability to clearly communicate why you chose a particular database, caching strategy, or service architecture is what distinguishes senior backend developers in the interview process.