Who is this Backend Developer interview plan for?

It is written for the interviewer, not the candidate: the hiring manager, engineer or panel member running the Technical Interview round for a Backend Developer role. It gives you a 60 min script to follow in the conversation — 11 questions with what each one is for and the signals to score against — so you are not writing the round from scratch the night before.

How is the 60 min split up?

Introduction (5 min), Backend Technologies (10 min), Databases (10 min), API Development (10 min), Security (10 min), Design Patterns (5 min), Closing (5 min). The timings are there so the round stays on schedule and every candidate gets the same shape of interview — which is what makes two candidates comparable afterwards.

What other rounds should I run for a Backend Developer?

A single round does not cover a whole role. The other rounds in this library for a Backend Developer are Behavioral Interview, Coding Test, Database Interaction Q&A and System Design Interview. Each is a separate plan you can use as it is.

Interview plan template

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Backend Developer interview questionsTechnical Interview round

A 60 min interview plan with a time-boxed script, what each question is for, and the signals to score against. Key skills: Backend Technologies, Databases, API Development, Security, Design Patterns.

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Introduction

5 min

•

Hi, I’m [YOUR_NAME], and I’m a [YOUR_TITLE] at [COMPANY_NAME]. I’m excited to learn more about your experience today.

•

Could you briefly introduce yourself and share what attracted you to apply for this position?

What this question is for, and what to listen for

Purpose

Assess communication skills, alignment with the role, and initial confidence.

Signals to score

Clear introduction provided
Relevant experience mentioned
Motivations for applying explained
Alignment with team values
Specific skills highlighted
Response is concise and organized
Understanding of role requirements

Follow-up questions

What excites you most about this position?
How does your background align with our team’s work?

•

Great, thank you for sharing! In the next 50 minutes, we’ll dive into some technical questions. Feel free to ask for clarification if needed.

Backend Technologies

10 min

•

Can you explain the differences between REST and GraphQL?

What this question is for, and what to listen for

Purpose

Evaluate knowledge of API development and understanding of different technologies.

Signals to score

REST and GraphQL differences explained
Use cases for each mentioned
Understanding of data fetching
Knowledge of flexibility in GraphQL
REST's statelessness understood
Mention of over-fetching/under-fetching
Awareness of tooling and libraries

Follow-up questions

How does REST handle data fetching?
What are some advantages of using GraphQL?

•

What are some common backend frameworks you have worked with?

What this question is for, and what to listen for

Purpose

Assess familiarity with backend frameworks and practical experience.

Signals to score

Frameworks like Node.js, Django, etc. mentioned
Experience with at least one framework
Understanding of framework strengths
Mention of community support
Knowledge of framework scalability
Awareness of framework limitations
Practical examples provided

Follow-up questions

Which framework do you prefer and why?
Can you give an example of a project using this framework?

Databases

10 min

•

How do you decide between using SQL and NoSQL databases?

What this question is for, and what to listen for

Purpose

Assess understanding of database types and decision-making skills.

Signals to score

SQL and NoSQL differences explained
Use cases for each type
Understanding of data structure
Mention of scalability
Knowledge of transaction support
Awareness of flexibility
Practical examples provided

Follow-up questions

What are the benefits of using SQL databases?
Can you describe a scenario where NoSQL is preferable?

•

What are some common database optimization techniques?

What this question is for, and what to listen for

Purpose

Assess knowledge of database performance improvement methods.

Signals to score

Indexing mentioned
Query optimization discussed
Use of caching
Database normalization
Partitioning/sharding
Understanding of load balancing
Practical examples provided

Follow-up questions

How does indexing improve performance?
Can you explain database normalization?

API Development

10 min

•

How do you ensure the security of an API?

What this question is for, and what to listen for

Purpose

Evaluate knowledge of API security practices.

Signals to score

Authentication methods explained
Use of HTTPS
Rate limiting discussed
Input validation
Mention of OAuth
Awareness of security testing
Practical examples provided

Follow-up questions

What is the role of authentication in API security?
How does HTTPS contribute to security?

•

Can you describe a challenging API you developed and how you overcame the challenges?

What this question is for, and what to listen for

Purpose

Assess problem-solving skills and practical experience.

Signals to score

Challenge clearly described
Solution process explained
Technologies used mentioned
Collaboration with team
Lessons learned
Outcome of the project
Reflection on improvement

Follow-up questions

What was the main challenge in this API?
How did you approach solving it?

Security

10 min

•

What are some common security vulnerabilities in backend systems?

What this question is for, and what to listen for

Purpose

Assess knowledge of security threats and prevention methods.

Signals to score

SQL injection mentioned
Cross-site scripting (XSS)
Cross-site request forgery (CSRF)
Data encryption
Secure coding practices
Awareness of security patches
Practical examples provided

Follow-up questions

How can SQL injection be prevented?
What is cross-site scripting?

•

How do you stay updated with the latest security practices?

What this question is for, and what to listen for

Purpose

Assess commitment to continuous learning and security awareness.

Signals to score

Following security blogs
Attending webinars/conferences
Participating in security forums
Reading security whitepapers
Engaging with security communities
Awareness of security certifications
Practical examples provided

Follow-up questions

What resources do you use to stay informed?
How often do you update your knowledge?

Design Patterns

5 min

•

Can you explain the Singleton design pattern and its use cases?

What this question is for, and what to listen for

Purpose

Evaluate knowledge of design patterns and practical application.

Signals to score

Singleton pattern explained
Use cases mentioned
Understanding of instance control
Mention of global access
Awareness of thread safety
Practical examples provided
Limitations discussed

Follow-up questions

What is the purpose of the Singleton pattern?
Can you give an example of its use?

Closing

5 min

•

Do you have any questions for me about the team or the company?

What this question is for, and what to listen for

Purpose

Gauge the candidate’s curiosity and interest in the role.

Signals to score

Thoughtful questions asked
Interest in company culture
Curiosity about growth expressed
Questions about role raised
Inquiries about team challenges
Engagement with responses shown
Desire to learn next steps
Focus on company values expressed

Follow-up questions

What interests you most about this team?
Are there any areas of the role you’d like to explore further?

•

Thank you for your time today. We’ll be in touch soon regarding the next steps.

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Interview Template

Position

Backend Developer

Round

Technical Interview for 60 min

Key skills

Backend Technologies, Databases, API Development, Security, Design Patterns

Backend Developer interviews — common questions

Who is this Backend Developer interview plan for?: It is written for the interviewer, not the candidate: the hiring manager, engineer or panel member running the Technical Interview round for a Backend Developer role. It gives you a 60 min script to follow in the conversation — 11 questions with what each one is for and the signals to score against — so you are not writing the round from scratch the night before.
What does the Technical Interview round assess?: This round is focused on: Backend Technologies, Databases, API Development, Security, Design Patterns. It works through Introduction, Backend Technologies, Databases, API Development, Security, Design Patterns and Closing, scoring against 72 observable signals, with follow-up prompts on all 11 questions for going deeper where an answer is thin.
How is the 60 min split up?: Introduction (5 min), Backend Technologies (10 min), Databases (10 min), API Development (10 min), Security (10 min), Design Patterns (5 min), Closing (5 min). The timings are there so the round stays on schedule and every candidate gets the same shape of interview — which is what makes two candidates comparable afterwards.
What other rounds should I run for a Backend Developer?: A single round does not cover a whole role. The other rounds in this library for a Backend Developer:
Behavioral Interview
Coding Test
Database Interaction Q&A
System Design Interview