51 software engineer interview questions

A software engineer with the right skills will expend little effort when designing and maintaining a software system. But, since the global developer population is expected to reach 28.7 million people by 2024, you have a challenging task ahead evaluating and choosing between your candidates.

Step one involves asking candidates to complete a skills assessment, but what should you do next?

You’ll need to have the right interview questions prepared in order to assess their soft and programming skills.

The great news is that this step has partially been done for you! Get some creative ideas from this article, in which we have listed 51 software engineer interview questions to help you hire top developers.

10 general software engineer interview questions

We’ve started this blog with general software engineer interview questions to help you better understand your candidates’ abilities. Select the questions that match your organization!

1. How would you outline what computer software is and describe it to someone in non-technical words?

2. Which technical skills are required to program efficiently?

3. Which non-technical (soft) skills are required to program efficiently?

4. Which programming language do you prefer when writing programming algorithms?

5. Can you name the essential stages of the software development process?

6. What are the main categories with which you can classify software?

7. What would be your definition of debugging in software development?

8. How are computer programs and computer software different?

9. How would you define software re-engineering?

10. What are the essentials of reviewing code?

5 of the most important general software engineer interview questions and their answers

Here are five of the most critical general software engineer interview questions taken from the above list and the answers you should be looking for as a recruiter.

1. How would you outline what computer software is and describe it to someone in non-technical words?

The best answers to this question will outline the main components of computer software in general terms, including user guides and documentation. They might provide a few examples of computer software that many organizations use and then explain clearly the specific computer software related to the job vacancy. 

Software engineers should also be able to confidently discuss the purpose of software — that it comprises many instructions that the hardware follows and enable the computer to perform tasks.

2. Which technical skills are required to program efficiently?

When answering this question, candidates should not only mention the programming skills required for an engineering position and knowledge of several frameworks, but they must also demonstrate that they have knowledge related to the business and how this affects the role of a software engineer. 

They should therefore be able to explain that they have the technical and business skills required. If they don’t have the right technical skills for your organization (for instance, they don’t know how to use the main programming languages used by your team), they must indicate their willingness to learn. 

3. Which non-technical (soft) skills are required to program efficiently?

A range of non-technical skills are essential for efficient programming and can make programming easier. Since working as part of a team is essential — particularly for code reviewing and mentoring new employees, candidates should mention their ability to collaborate, communicate, use time management approaches, and consistently use empathy when completing projects.

4. Which programming language do you prefer when writing programming algorithms?

Software engineer candidates should have knowledge of the high-level programming languages, including C skills or Pascal, since they will be using them frequently. But, again, your candidates might not mention the specific programming languages regularly used by your team. In this case, they must explain how they would learn to adapt to them.

5. Can you name the essential stages of the software development process?

This question is linked to the SDLC (or software development lifecycle), which consists of seven stages. Candidates should recognize all stages, as they’ll be working on projects that will go through each stage, including planning and analysis of the requirements, design, implementation, development, testing, code reviewing documentation, and the maintenance period.

22 software engineer interview questions related to technical definitions 

The next 22 software engineer interview questions are related to technical definitions and concepts frequently used in the industry. Take a look and choose the questions that suit your organization’s brand.

1. Explain some of the SDLC models.

2. Can you explain what verification is in software development?

3. Can you explain what validation is in software development?

4. Define the elements you should consider in the System Model Construction.

5. What are the main tools you use to monitor the software’s requirements?

6. How are stubs different from mocks?

7. Which SDLC model would you say is superior to others?

8. How would you describe what software scope means?

9. How would you find out how big a software product is?

10. How would you define function points?

11. Can you describe what is meant by the decomposition estimation technique?

12. Can you describe what is meant by the empirical estimation technique?

13. Can you outline and briefly mention configuration management?

14. Which approaches do you use for configuration management?

15. Can you outline what is meant by functional requirements?

16. Can you outline what is meant by non-functional requirements?

17. Describe modularization.

18. How is Pseudo Code different from structured English?

19. Outline structured design and what it means.

20. Can you describe functional programming?

21. Define what CASE means. 

22. Outline the key differences between threads and processes.

5 of the most vital software engineer interview questions related to technical definitions and their answers

This next list comprises the five vital technical software engineer interview questions from the above list and explains what to look for in the best responses.

1. Explain some of the SDLC models.

Knowledge of SDLC models is crucial in software development as they influence how the job is carried out. Some of the key SDLC or software development lifecycle models that your candidates must be familiar with include the Agile model as well as the Waterfall method. Others include Scrum, Kanban, Prototyping, and the Spiral model.

You should consider candidates who can outline some information on these, but the most important thing is that they can adapt to the SDLC model that your organization uses even if they haven’t used it in the past.

2. Which SDLC model would you say is superior to others?

Agile is being used more frequently as a software development lifecycle model, but answers to this question might not necessarily stipulate that one model is better than the others. SDLC models are typically chosen to match the development project. Therefore, candidates should be able to describe the advantages of each SDLC model when used for particular projects. 

3. Define what CASE means. 

These four letters (CASE) refer to “computer-aided software engineering.” This is typically a group of programs classed as automated applications that engineers use to achieve goals efficiently in the software development lifecycle.

The best answers to this question will outline a few advantages of these tools, including the ability to keep the cost of the software development process low and boost the quality and chances of accomplishing the user’s requirements.

4. How would you find out how big a software product is?

There are a couple of approaches that software engineers can use to determine the size of a product. One of these might involve counting the code’s lines, while another might add up the function points.

Function points also help engineers to assess new development projects or program enhancements. 

5. Describe what modularization is.

This question will help you understand your candidates’ technical knowledge, and the best answers will demonstrate whether they’re knowledgeable of the various ways that modularization can increase the code’s quality for every separate section. 

Modularization refers to the action of breaking down code and, therefore, a program’s functionality into distinct modules. These modules enable engineers to easily add separate and smaller modules while avoiding the negative and complex influence of the program’s other functions and keeping development time low.

16 behavioral software engineer interview questions

Now we’ll move on to 16 behavioral software engineer interview questions from which you can choose. Use them to help you evaluate your candidates’ approaches to challenging circumstances.

1. Have you ever made a mistake when programming? 

2. Have you ever encountered a problem when programming? 

3. Name a side project you’ve been passionate about.

4. What do you understand about “Agile” development? Why is it crucial?

5. Have you ever had to explain software programming to non-technical stakeholders? What was your approach?

6. Can you talk me through a time when you used a design pattern in a project? 

7. Can you talk about a time when team collaboration was required to solve a challenging problem?

8. Can you talk about a time when you didn’t see eye-to-eye with a team member? How did you resolve the problem?

9. Describe the critical principles that you follow as a software developer. 

10. Have you ever had to adapt to a new situation as a software engineer?

11. Can you talk about a time when you suggested and implemented an approach to enhance a project?

12. Can you give some insight into your creativity with software engineering and explain a situation in which you used a unique solution for a complicated problem?

13. Can you describe a time when you were just on time for a deadline but struggled to meet it? How would you carry out the project differently now?

14. Has there been a circumstance in which you missed a deadline? What strategy would you use to complete the task now?

15. Describe some methods you use to stay organized.

16. Can you talk about a time when you had to plan for a software engineering project? 

Recommended reading: More behavioral questions for software engineers.

5 of the most vital behavioral software engineer interview questions and their answers

We’ve provided five critical behavioral software engineer interview questions in this section with answers indicating your candidates’ proficiency.

1. Have you ever made a mistake when programming or learning how to code? 

Your candidates might select from a broad range of mistakes, including writing messy code and ignoring code quality, forgetting or deciding not to plan, or failing to practice. Whichever mistake they might have made, look for answers that indicate that they could learn to avoid these errors.

For instance, if your candidate wrote messy code as a beginner, which steps did they take to tidy up their coding quality? Did they learn about well-structured code, and how did they achieve this?

If they initially failed to plan before starting a project, did they actively seek to understand why planning is critical? And how have their current projects increased in quality thanks to the implementation of their new planning approach?

2. Name some side projects you’ve been passionate about

Since passionate software engineers should be interested in building their coding, creative, and technical skills, candidates should be able to mention a side project that they have worked on in the past or are working on now.

Do some digging during the interview process to find out why your candidates opted to pursue the projects they are working on and what skills they have learned so far. It’s vital to ask follow-up questions about such side projects as they’ll give you a better understanding of your candidates’ strengths and passions.

3. Describe the critical principles that you follow as a software developer. 

This question is crucial because the answers you receive will inform you how dedicated and passionate your candidates are. They may mention that they avoid repetition in code and value the “don’t repeat yourself” principle. They may mention that keeping things simple is vital or show that they know the SOLID principle.

The principles they outline are important, but it’s also vital that your candidates can explain how these principles help them write better code. 

4. Have you ever had to adapt to a new situation as a software engineer?

Your candidates will need to adapt to new circumstances in your organization, which is why this question is important. Perhaps they outline a situation where they had to learn a new programming language or framework. Perhaps they had to grow accustomed to a new software development lifecycle model. 

Candidates should easily demonstrate that they have the transferable skills required and outline a circumstance where their efforts to adapt helped them accomplish a goal or milestone.

5. Can you give some insight into your creativity with software engineering and explain a situation in which you used a unique solution to a complicated problem?

Sometimes creative solutions are required, which means your candidates should be able to think creatively. Candidates who can demonstrate critical thinking skills and creativity are worth following up with. 

For instance, they might mention that a project requires a feature flag or a cloud license development project requires the team to acknowledge the end user’s thoughts. If so, what was the outcome of these creative solutions? Ask the right questions to determine the benefits of your candidates’ creativity.

3 software engineer interview questions related to time and project management

The final three software engineer interview questions are related to time and project management. Which questions will you choose to ask your candidates?

1. Can you outline some useful software metrics?

2. Are you aware of any software engineering project management tools? 

3. Describe a time when you had to provide an estimate for a client. 

3 answers to the critical software engineer interview questions related to time and project management

Below, we’ve outlined the things you should look out for in candidates’ answers to the critical software engineer time and project management interview questions.

1. Can you outline some useful software metrics?

Since software metrics are critical for understanding the progress made on a project, ask candidates this question to learn whether they are aware of the most important ones. Proficient candidates might mention the length metrics related to requirement, the number of lines of code, or testing metrics related to the product. 

2. Are you aware of any software engineering project management tools? 

A few software engineering project management tools your candidates might mention include status reports, Gantt charts, and Kanban tools. If they haven’t used the project management tools used in your organization, ask them whether they can learn how to use them. Explore this a little further by asking how they’d adapt to your tools.

3. Describe a time when you had to provide an estimate for a client. 

It’s not only clients who require estimates; stakeholders and engineering managers will need an estimate to evaluate progress and set the scope of work for certain milestones. Can your candidates recognize the many factors that may affect the estimate, including bug fixing and testing? 

Since an accurate estimation is crucial, assess whether your candidates have a realistic understanding of how long a particular project will take by asking what steps they will take to arrive at a reasonable estimation.

5 pieces of advice for asking your candidates these software engineer interview questions

Before we close this article, here are five pieces of advice that you should bear in mind when asking your candidates these software engineer interview questions.

1. Make sure that skills assessments are the initial approach you use to evaluate your candidates’ skills. The reason skills assessments are especially ideal for your software engineer hiring process is that technical skills tests make it easy to omit unskilled candidates from the hiring process. This immediately shortens your time-to-hire.

2. Think about the qualities you expect from your candidates. Your candidates should have some of the following qualities to perform well within your team and complete projects easily:

• Exceptional technical abilities

• Good active listening skills and communication abilities

• Critical thinking skills

• Adaptability and the will to learn new techniques

3. Try asking candidates questions that are unique to your organization and reflect your brand. Generic interview questions do nothing for the interview and candidate experience.

Generic questions even force candidates to lie (according to Inc), so select questions that enhance the candidate experience and reflect the pressing issues your company is facing at this very moment. This might be related to a cloud license issue or a problem with communication within teams — but ensure that it’s brand-related.

4. Allow your candidates to ask questions about your organization. Since proficient candidates will strive to learn continuously, allow them to learn more about your organization by switching roles during the interview. Answer their questions as best as you can to provide them with a clear view of your organization. 

For instance, if your candidates ask about remote working, inform them about remote working in your company. Perhaps technical issues are discussed asynchronously from time to time.

5. Observe your candidates’ body language. This communication skill can help you understand how confident your candidates are during the interview. Non-verbal cues can give you an insight into how your candidates will perform on the job. 

For instance, do your candidates maintain eye contact? If they don’t, perhaps they might struggle to work within a team that frequently communicates in Scrums.

Tailor your software engineer interview questions to your brand

So, we’ve reached the end of the article. If you were wondering how to hire an expert developer or software engineer, don’t forget that interview questions are important. For more ideas, check out our selection of the best site reliability engineering interview questions or Jenkins interview questions to identify top talent.

Here are the takeaways from this article that you should keep in mind:

• Use skills assessments at the very start of the hiring process. They’ll help you minimize the time it takes to hire a candidate.

• Remember, you should avoid generic interview questions. Try to tailor your software engineer interview questions to your brand to enhance the candidate experience.

• Switch roles with the candidate towards the end of the interview — let them ask you questions and answer them as well as you can.

Develop your software engineer interview questions and tailor them to your brand. With the right questions, you’ll learn whether your candidates are the right fit and you’ll hire a top software engineer with little difficulty! Try TestGorilla for free.

If you still need more pointers in hiring software engineers, read our detailed guide on how to hire a software engineer.