18 Interview Questions for Full-Stack Engineers [2023 Career Guide]

Are you on the hunt for a full-stack engineering job? Look no further! In this article, we’ll cover the role of a full-stack engineer, the skills and qualifications needed to excel in this position, and the most common interview questions you can expect to be asked along with a brief overview of why it is important.

Featured photo

What is a Full-Stack Engineer?

sketch of a mobile app designed by a full stack engineer

A full-stack engineer is a software developer who has a diverse set of skills, including the ability to work on both the front-end and back-end of a web application. They have a solid understanding of everything from HTML and CSS to databases and server-side languages. 

They’re comfortable working with a wide variety of technologies and can quickly learn new ones as needed.

To be a successful full-stack engineer, you should have experience with:

  • Front-end technologies such as HTML, CSS, and JavaScript
  • JavaScript frameworks such as React or Angular
  • Back-end languages such as Python, Ruby, or Java
  • Database management
  • Understanding of web architecture and HTTP protocol

If this all sounds familiar, you might just be qualified! But to fully prepare for a full-stack engineering job interview, here are some common questions you should be prepared to answer.

18 Interview Questions for Full-Stack Engineers

When you’re interviewing for a full-stack engineering position, you can expect to be asked a combination of technical, behavioral, and situational questions.

Technical Questions

lines of code on a black screen

All of these questions are geared toward testing your technical knowledge and proficiency.

1. Explain the difference between server-side rendering and client-side rendering.

This question tests your understanding of web architecture. Server-side rendering is when the application code is executed on the server and generates HTML which is then sent to the client. Client-side rendering occurs when the application code is executed in the browser, allowing for more dynamic interaction with the page.

2. Can you explain the difference between WebSockets and long polling?

Web sockets and long polling are two different methods of maintaining a constant connection between the client and server. Understanding the differences between them is necessary for developing efficient and responsive web applications.

3. How would you optimize a slow database query?

This question tests your knowledge of database optimization techniques. You should be prepared to explain techniques such as indexing, caching, and query optimization.

4. What is your experience with version control systems such as Git?

Version control systems are essential for collaborating on code, and you should be able to explain how they work and describe your experience with them.

5. Explain how you would set up a development environment on a new machine.

This question tests your ability to explain the steps necessary for setting up a development environment on a new machine, such as installing necessary software and configuring the environment.

6. Can you describe the request-response cycle in a web application?

To do well in your interview, you’ll need to demonstrate a solid understanding of the fundamentals of web architecture. Can you verbally explain how HTTP requests are sent from and processed by the server? Additionally, can you articulate how servers transmit responses back to clients?

7. How do you handle security issues such as SQL injection and cross-site scripting (XSS)?

Security is an important aspect of any web application and employers will be looking to see if you have the knowledge and experience needed to handle these types of issues. To answer this question, you should be prepared to discuss the various tools and techniques available for preventing these types of attacks. Additionally, it’s beneficial to provide an example of how you have implemented such security measures in the past.

8. Have you ever used a front-end framework like React or Angular? How do you feel about them?

Employers will be looking to see if you have any experience with popular front-end frameworks, and this is a great opportunity to show off your familiarity with them. Explain your experience, the pros and cons of each framework, and how you think they can be used in web development projects.

9. Have you ever deployed an application to a cloud platform like AWS or Azure?

The ability to deploy applications to cloud platforms is an increasingly important skill for full-stack engineers, so be prepared to answer questions about your experience with doing so. Be sure to talk about the different processes and tools you’ve used in doing so, as well as any challenges that you have faced.

Behavioral Questions

two web designers working together at a dry erase board

Behavioral questions are designed to get at how you approach problem-solving and collaboration with others.

10. Give an example of a project you’ve worked on that required you to work with a team.

When answering this question, you should provide an example of a project where you were part of a team and explain the role that you played in the project. Additionally, you should discuss the challenges that you faced and how you overcame them.

11. Can you tell me about a time when you had to troubleshoot a difficult problem?

To answer this question, you should provide an example of a difficult problem that you faced and explain how you went about troubleshooting it. Demonstrate how you were able to narrow down the issue and come up with a solution.

12. How do you stay current with the latest developments in web technologies?

This question is intended to assess your commitment to staying up-to-date with the latest trends and advancements in web development. Talk about any conferences or workshops you attend, industry blogs that you follow, and/or any other methods you use to stay abreast of the latest technologies.

13. Tell me about a time when you had to work on a rushed deadline and how you handled it.

When it comes to this question, give an illustration of a tight timeline you had to work with and explain how you managed it. Describe any tactics utilized to prioritize jobs and handle the time pressure while still meeting the deadline. And be sure to share any obstacles experienced and what steps were taken in order to overcome them.

14. Can you tell me about a time when you had to make a difficult decision related to your work?

When answering this question, you should provide an example of a difficult decision related to your work and explain how you went about making the decision. Talk about how you weighed the pros and cons of each option, consulted with colleagues or mentors, and ultimately decided on what course of action to take. Then explain the outcome of your decision and how it affected the project in question.

15. How do you handle criticism or feedback on your work?

For this one, explain how you take feedback from colleagues or clients on your work and use it to improve. Discuss any specific strategies that you employ to ensure that feedback is taken into account and used constructively. Furthermore, discuss how accepting and learning from criticism can lead to tremendous growth as a developer and enable your projects to reach their fullest potential.

Situational Questions

two businessmen talking around a laptop

Situational questions are designed to get at how you handle various scenarios.

16. What would you do if a team member was consistently underperforming?

If you’re asked this question, explain how you would approach the situation in a way that is supportive and constructive. Talk about strategies such as providing additional training, offering guidance on individual tasks, or talking through any issues that may be causing the team member to struggle.

17. How would you handle a situation where a client is unhappy with the work you’ve delivered?

For this one, talk about how you would handle the situation in a professional and diplomatic manner. Discuss how you would take responsibility for any mistakes and work with the client to identify a solution.

18. You’re working on a feature that’s taking longer to build than you anticipated. The deadline is approaching, and you’re not sure if you’ll finish on time. What would you do?

In this scenario, explain how you would prioritize tasks in order to ensure that the most important elements of the project get done on time. Talk about how you would communicate with the client to let them know the timeline, and discuss any creative solutions that may help you finish the project faster.

Preparing for Your Interview as a Full-Stack Engineer

As a full-stack engineer, you will be expected to have a diverse set of skills, including the ability to work on both the front-end and back-end of a web application. Being prepared for these types of interview questions will help you showcase your skills and experience, and ultimately increase your chances of landing the job.

Remember to practice explaining your past experiences and be able to provide concrete examples of your qualifications. And don’t forget to be confident and enthusiastic about your passion in full-stack engineering. Good luck with your interview!