Full Stack Developer Interview Questions: What to Expect in 2024

Full-stack developers contribute to the entire development of websites, including both front-end and back-end development. Where front-end developers work exclusively on the user interface or visual portion of a website, back-end developers build the underlying structure of websites. Some companies hire both front-end and back-end developers, while others hire full-stack developers with the skills to handle all portions of the development process. 

Discover what it takes to start a career as a full-stack developer and gain insight into interview questions you may receive during your job hunting process. 

Industry outlook and skill requirements

According to data from Lightcast ™, web developers earn an average yearly salary of $77,304 [1]. According to Glassdoor, full-stack developers earn an average annual salary of $89,919 [2]. 

Skills, location, experience, and industry can impact your salary. The US Bureau of Labor Statistics anticipates significant growth in web development positions in the coming years. From 2022 to 2032, it projects over 19,000 openings yearly and a 17 percent increase in overall employment [3]. 

Full-stack developer jobs require you to possess the technical skills of both a front-end and back-end developer and workplace skills. Here are some critical skills employers look for when hiring a full-stack developer:

• Front-end languages, including HTML, CSS, and JavaScript 

• Back-end languages, such as Python and Java

• Structured query language (SQL)

• Web architecture

• Problem-solving 

• Collaboration and communication

Read more: Front-End vs. Back-End Developer: Understanding the Differences

8 full-stack developer interview questions

To prepare for your interview, look at some of the questions you may face and devise a plan for answering them. Practice these common full-stack interview questions to ace your next interview:

1. What programming languages are you familiar with?

What they’re really asking: What is your in-depth programming knowledge?

Full-stack development uses multiple applicable languages, each with different advantages. It is important to demonstrate that you understand and know the different programming languages and how to use them. 

You will want to display experience in popular programming languages that are standard throughout the industry. Common languages seen widely in full-stack development include Python, HTML, CSS, and JavaScript. Success in full-stack development requires skills in several key languages since the position manages the entire software life cycle from the beginning to the final product.

Other forms this question could take:

• What is your favorite programming language to use?

• What back-end or front-end programming languages do you have the most expertise in?

2. What is pair programming?

What they’re really asking: Can you collaborate on a team?

Pair programming is a collaborative system or technique where one person writes code while the other observes to ensure the code is written correctly. This allows you to identify bugs sooner, and developers can share knowledge to write better code. 

Pair programming can be especially useful for working with new hires. Your interviewer wants to know how you work on a team with other programmers and if you have experience collaborating while programming. You may want to give an example of when you have collaborated using pair programming and what you learned from collaborating on that team.

Other forms this question could take:

• Tell me about a time you collaborated with a team of programmers.

• Why is pair programming beneficial?

3. Explain callback hell.

What they’re really asking: Can you handle complex problems?

Callback hell happens when complex nested callbacks are stacked on one another in JavaScript. This results in complex code that is challenging to maintain and read.

Your interviewer wants to evaluate your knowledge and ability to handle errors in JavaScript. By learning the techniques to deal with callback hell, you can be better prepared to solve the problem and write clean code to prevent it.

In your interview, give examples of when you’ve dealt with callback hell or similarly complex programming situations.

Other forms this question could take: 

• How can you avoid callback hell?

• Describe a time you had to solve a complex coding problem.

4. What is continuous integration?

What they’re really asking: What’s the depth of your coding knowledge?

Continuous integration is the regular merging of code changes to the main branch of the source code to test changes, and it allows you to fix errors more easily and early in the development process. Organizations utilize continuous integration (CI) to minimize bugs and improve development efficiency.

Ultimately, having skills in continuous integration helps improve the quality of your software and the efficiency of releasing updates. In your interview, it’s important to highlight your coding experience with continuous integration and how you’ve worked to make your software error-free and functional. 

Other forms this question could take:

• What is continuous delivery (CD)?

• What are the benefits of utilizing CI and CD?

5. What is DevOps?

What they’re really asking: Do you know how to communicate between teams?

DevOps combines development and operations to improve former workflow strategies by opening communication and merging these processes, allowing for faster production speed. Continuous integration and delivery are both components of DevOps, and communication between development and operations teams benefits the production process.

Your interviewer wants to know if you have experience and knowledge of how development and operations teams unite to create more efficient delivery and planning of applications and software. You may want to give an example of when you worked on a DevOps team or collaborated between teams.

Other forms this question could take: 

• How does DevOps improve efficiency?

• What are the advantages of DevOps?

6. How would you optimize a website for faster load times?

What they’re really asking: What is your process for improving software?

A website's usability is largely dependent on its loading speed. Strategies you can use to optimize load times include using image files that aren’t larger than necessary, compressing JavaScript, CSS, and HTML files, using a content distribution network, and avoiding redirects. Ensuring fast load times is critical for high conversion rates and revenue generation through your website.

Your interviewer wants to know if you know how to improve their systems and what your process would be to implement those changes. To showcase your experience, give examples of times you’ve optimized software or websites.

Other forms this question could take:

• What are the possible causes of slow website load times?

• How would you optimize an existing website?

7. What skills are most important for a full-stack developer?

What they’re really asking: How well do you understand the role and responsibilities of a full-stack developer?

Full-stack developers must have a diverse skill set covering back-end and front-end development skills. HTML, CSS, and JavaScript are all crucial full-stack developer languages and skills to know since they are key building blocks of websites. Python, Java, and Ruby are also critical to back-end development, so having a skill set capable of working on both sides of a website is crucial. 

To set yourself apart in an interview, it may be helpful to build a portfolio of your skills to demonstrate your experience in different programming languages and tools to employers.

Other forms this question could take:

• What front-end and back-end skills are most important in full-stack development?

• What are some full-stack developer skills that set you apart from other candidates?

8. What interests you about full-stack development?

What they’re really asking: Who are you, and how well do you align with the role?

The interviewer wants to gauge your understanding and overall interest in the position. You can share your career goals with the interviewer to demonstrate your enthusiasm for the position. It’s helpful to research the company and have reasoning behind why you would be a good fit when preparing for this question. 

You can also use this opportunity to explain how your skills and strengths make you a strong candidate.

Other forms this question could take:

• What interests you about working here?

• What are your long-term career goals?

Questions to ask the interviewer

At the end of an interview, asking the interviewer questions is a good idea to determine if their company is a good fit for you and show the interviewer your interest in learning more about the position and their company. 

Some questions you can prepare to ask in your next interview include:

• What skills are most important to succeed in this position?

• What does a typical day week look like for a full-stack developer at your company?

• What does your onboarding process look like?

• Can you tell me more about the company culture?

• Who would I report to?

• How many team members would I be working on projects with?

Tips for preparing for your interview

Below are additional tips to ensure you’re fully prepared for your next interview.

Prepare to answer introductory questions.

Before answering more specific full-stack development-related questions, the interviewer will likely begin by asking you some introductory questions about yourself, such as:

• What keeps you motivated?

• What are your career goals over the next five years?

• What are you hoping to achieve in this role?

• What do you know about our company?

Use the STAR method.

The STAR method of answering behavioral interview questions stands for situation, task, action, and result. When answering a behavioral question, you can first describe your situation, followed by the task or your responsibility, then the actions you took to solve the problem and the results of your work. This method allows you to articulate your answer to the interviewer clearly.

Research the company.

Before your interview, it's helpful to learn more about the company you are interviewing with to familiarize yourself with its culture and position. You can do this by exploring the company website, reviewing the job description, checking its social media pages, and researching competitors to get a feel for the industry.

Know your salary expectations.

The interviewer may ask you a question to gauge your salary expectations. Before your interview, research industry standards online. When answering this question, you can suggest a range based on the industry standards you identified or express your flexibility.

Getting started with Coursera

When interviewing for a full-stack developer role, you must be ready to answer wide-ranging questions about your background, interests, and skills. On Coursera, you can find highly-rated courses to help you prepare for your career as a web developer. Johns Hopkins University’s HTML, CSS, and JavaScript for Web Developers course can help you learn the basics of web development in prominent coding languages. You can also earn a Meta Front-End Developer Professional Certificate, where you can build job-ready skills to build interactive web pages.