37 Back-End Developer Interview Questions (With Answers)

By Ben Rand

Updated July 26, 2022 | Published September 10, 2020

Updated July 26, 2022

Published September 10, 2020

Ben Rand is a guest contributor specializing in technology topics.

Back-end software development powers the web by enabling connections between end users and the databases that make up the internet. Back-end developers skilled in programming languages, databases, caches, servers and APIs provide essential services to organizations that rely on computers to do business. Before your interview for a back-end developer position, you may want to review development basics and practice answering commonly asked interview questions. 

In this article, we share 37 back-end development interview questions and provide example answers in various categories to help you prepare for your job interview.

Related: Top 6 Common Interview Questions and Answers

Jenn, an Indeed Career Coach, breaks down the intentions behind employer's questions and shares strategies for crafting strong responses.

10 general questions

Here are general questions you may encounter in your back-end developer interview. The purpose of these questions is to help your potential employer get to know you:

  1. Why are you interested in this position?

  2. How did you hear about our company?

  3. What can you tell us about yourself?

  4. How would you describe your work or management style?

  5. Do you prefer to work individually or as a team member?

  6. How do you stay current with back-end development trends?

  7. In your last position, what were your primary job responsibilities?

  8. Where do you see yourself professionally in five years?

  9. What words would your coworkers use to describe you?

  10. What do you find most satisfying about this type of work?

Related: 31 Smart Questions To Ask in a Job Interview

11 questions about experience and background

In addition to general questions, a prospective employer looking for a software developer likely wants to know more about your experience and technical background. These questions assess your working styles and preferences to evaluate your previous experience:

  1. How did you get into coding?

  2. What's your greatest strength as a coder?

  3. If you were in charge of a tech company, how would you manage its developers?

  4. Tell me about a time when someone criticized your work and explain how you responded.

  5. How do you deliver negative feedback to members of your development team?

  6. Have you ever worked on a team project where you felt you were doing most of the work? How did you manage that?

  7. Tell me about the coding accomplishment you’re most proud of?

  8. What's the most challenging decision you've faced in your career?

  9. What’s your experience with object-oriented programming (OOP)?

  10. What’s your favorite programming language, and why?

  11. What’s your experience with GoTo, and do you prefer structured programming?

Related: How To Pass a Job Interview

10 in-depth questions

Your interviewers may also want to gain a sense of your specific aptitudes. Preparing for in-depth questions may allow you to communicate your knowledge and talk about your hard skills. Here are some in-depth questions your interviewer may ask:

  1. How would you explain the difference between design and architecture?

  2. Define the terms “stack” and “heap.” What’s a stack overflow?

  3. What's the difference between cohesion and coupling?

  4. When is refactoring useful?

  5. What do the terms “high cohesion” and “loose coupling” mean?

  6. What are the pros and cons of holding domain logic in stored procedures?

  7. What do you think makes object-oriented design the preferred approach?

  8. What do you find lacking in your favorite development language? How do you cope with those gaps?

  9. What do classes and closures have in common?

  10. When are anonymous functions useful?

Related: Hard Skills vs. Soft Skills: What's the Difference?

6 back-end developer interview questions with sample answers

You’re likely to encounter interview questions that can highlight the breadth of your knowledge. The success of your back-end developer interview can depend on how well you present yourself and your experience. Employers appreciate honesty and often want to see how you handle situations that require research and information gathering. 

Before your interview, be sure to review the basics of back-end development. It’s also helpful to practice answering interview questions and learn about interviewing best practices. Here are some example back-end development interview questions with sample answers:

1. What are the seven layers in the OSI system model?

Network-specific questions like this require direct factual answers. Interviewers use them to gauge your basic knowledge of network terms and processes. In your answer, try to exhibit both your theoretical and practical knowledge.

Example: "In the Open Systems Interconnection model, tracing how information moves from one application through a physical device to software in another computer requires moving through seven abstract layers with specific functions. These layers are physical, data link, network, transport, session, presentation and application.”

Related: Presentation Layer of the OSI Model: Definition and Function

2. What’s a reverse proxy?

Interviewers may ask questions like this to gain a better sense of your knowledge. This question can allow you to expand on related topics as well. For instance, after explaining a reverse proxy, you also can discuss its opposite, which is the forward proxy.

Example: "A reverse proxy acts as an intermediary, retrieving resources from a server and returning them to a client, so it appears that the information originates from the proxy server itself. The forward proxy, also an intermediary, is what the client puts between itself and another server.”

3. What's the difference between threads and processes?

Interviewers ask foundational knowledge questions like this to check your specific competence. You can use questions like these as an opportunity to show you have a practical understanding of key back-end terms.

Example: "A process is an active program being executed, while a thread is a lightweight process that a scheduler can manage independently. Threads also make up processes. Since threads are quicker at context switching, an OS can stop one thread and run another much faster than stopping and starting a process."

Related: The Difference Between Multithreading and Multiprocessing

4. What steps would you take to use mysqldump to restore MySQL?

Expect interviewers to include some language-specific questions to check your coding skills. Answer in simple terms, outlining your approach to the programming question. If interviewers want technical specifics, they usually ask for them.

Example: "First, I'd create a new database using MySQL and give it the same name as the lost database. I'd check to see if the database name was in the root directory, then determine whether I should include the server name as well.”

Related: Top 40 MySQL Interview Questions (With Example Answers)

5. If you have a limited amount of memory, how would you handle a large amount of data?

Open-ended questions like this usually have multiple right answers, and the interviewer wants to see your unique approach. Consider how you’d address the issue in a real-life setting and share your opinion, and explain why you chose your answer.

Example: "I would break up the large amount of data into small chunks. I’d do this by using an external sort or merge sort. I think this would be the fastest and simplest option.”

6. Define and explain these nine server response error codes: 200, 201, 204, 301, 400, 401, 404, 409 and 500.

Your interviewer typically asks this when they want to know the depth of your error knowledge. Address each part in order, explaining what the code means and what caused the error.

Example: “200 means “OK” and everything went well. A 201 “Created”' message means the system created a resource at the client's request. A 204 “No Content” code means the server didn't send back a status. A 301 “Moved Permanently” message means a client-triggered action changed the resource URI. A 400 “Bad Request” error refers to a client-side error. 

If the client doesn't provide the correct authentication, you see a 402 “Unauthorized” code. A 404 “Not Found” return means it didn’t find a mapped resource. An inconsistent or impossible state returns code 409, “Conflict.” Server-side errors generate code 500, described as, ‘“Internal Server Error."

Related: 20 Database Testing Interview Questions

10 jobs similar to back-end developers

If you're pursuing a job as a back-end developer, you may have many career options. Here are 10 jobs similar to back-end developer that might provide opportunities for development:

  1. Front-end developer

  2. Full-stack developer

  3. Software engineer

  4. Computer programmer

  5. Data analyst

  6. IT technician

  7. Web developer

  8. Cybersecurity specialist

  9. Data scientist

  10. Chief information officer

Please note that none of the companies mentioned in this article are affiliated with Indeed.

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