Backend Developer Interview Questions for IT Hiring

Introduction

Hiring the right Backend Developer is critical for Information Technology teams that rely on stable, scalable server-side systems. A strong backend hire improves performance, reliability, and the team capacity to deliver features.

This guide includes practical Backend Developer interview questions across basic, intermediate, and advanced levels, plus pre-screening one-way video interview questions you can use on ScreeningHive to shorten time to hire and standardize assessments.

Backend Developer Interview Questions

Basic Backend Developer Interview Questions

• What is a RESTful API and what are its core principles?
• Explain the difference between SQL and NoSQL databases and when to use each.
• Describe the common HTTP methods and their typical uses.
• What does ACID mean in the context of relational databases?
• How does caching improve backend performance and what are common caching strategies?
• What is the difference between authentication and authorization?
• Explain the purpose of load balancing and a simple way to implement it.
• What is an ORM and what are the advantages and potential drawbacks of using one?

Intermediate Backend Developer Interview Questions

• Design an API endpoint to return paginated results. What parameters and response structure would you use and why?
• Your service reports high latency for a specific query. How would you diagnose and resolve the issue?
• Describe how you would implement transactions across multiple microservices to maintain data consistency.
• How would you design a schema migration process for a live production database to minimize downtime?
• Explain how you would implement rate limiting to protect an API from abuse.
• Describe a caching strategy for frequently updated but read-heavy data.
• How would you approach logging and monitoring to ensure observability of backend services?
• Walk through a CI/CD pipeline you would set up for a backend application. What checks and stages are essential?
• How do you secure sensitive data at rest and in transit in a backend system?
• Provide an approach to testing backend services, including unit, integration, and end-to-end tests.

Advanced Backend Developer Interview Questions

• Design a scalable backend system to handle millions of daily requests. Explain your choices for architecture, data storage, and scaling.
• When would you favor eventual consistency over strong consistency and how would you handle client expectations?
• Explain database sharding and partitioning strategies you have used or would recommend for large datasets.
• How would you optimize end-to-end latency in a distributed service environment?
• Describe approaches to achieve fault tolerance and graceful degradation in a critical backend service.
• Discuss best practices for authentication and authorization at scale, including token management and rotation.
• How do you perform capacity planning and cost optimization for cloud-hosted backend infrastructure?
• Explain when to use CQRS and event sourcing and the tradeoffs involved.
• How do you lead technical decisions, document architecture choices, and manage tradeoffs with stakeholders?
• Share strategies for conducting effective code reviews and mentoring junior backend engineers to raise team quality.

Pre-Screening Video Interview Questions for Backend Developer

These pre-screening interview questions are ideal for one-way video interviews on ScreeningHive. Use them to evaluate technical fit, communication, and problem-solving before scheduling live interviews.

1. Describe a recent backend project you led. What was the architecture and what technical tradeoffs did you make?

   This question evaluates practical experience, design reasoning, and the candidate's ability to explain technical decisions clearly.

2. Walk through how you would debug a slow API endpoint from first contact to resolution.

   This question assesses troubleshooting skills, use of metrics and logs, and familiarity with performance tools.

3. Explain your approach to designing a data model for a feature that must scale and support frequent reads.

   This checks data modeling skills, awareness of indexing, normalization, and performance considerations.

4. How do you ensure code quality and reliability in backend services? Provide examples of tests and processes you use.

   This evaluates testing practices, continuous integration habits, and commitment to maintainable code.

5. Describe your experience with deployment and rollback strategies for production releases.

   This reveals experience with CI/CD, blue green or canary deployments, and incident mitigation techniques.

Conclusion

This collection of Backend Developer interview questions helps hiring managers, recruiters, and candidates prepare for focused evaluations across basic, intermediate, and advanced topics. Using structured questions improves consistency and speeds decision making.

Use these Backend Developer interview questions and pre-screening interview questions to build a reliable, repeatable hiring process for your IT teams.