Justworks Software Engineer Interview Questions + Guide in 2025

Justworks provides a supportive and casual work environment where employees can thrive while solving essential HR issues for businesses. They are data-driven and consistently iterating on their innovative solutions, focused on enabling businesses to grow without being bogged down by administrative tasks.

As a Software Engineer at Justworks, you will be an integral part of the Marketing Website team, responsible for designing, building, and maintaining customer-facing applications that enhance the Justworks platform. Key responsibilities include collaborating with cross-functional teams, building and iterating on high-quality designs and features, and ensuring the performance and security of the applications. A strong foundation in frontend technologies, particularly JavaScript/TypeScript, is essential, along with experience in frameworks like React and familiarity with service-oriented architecture.

In this role, Justworks values qualities such as good judgment, resourcefulness, teamwork, and a commitment to continuous learning. A successful candidate should demonstrate a proactive attitude toward problem-solving and possess the ability to thrive in a collaborative environment. They should also be comfortable communicating complex technical concepts to both technical and non-technical stakeholders.

This guide will help you prepare for your interview by providing insights into the key competencies Justworks seeks, as well as the types of questions and challenges you may encounter, allowing you to present your best self during the interview process.

The interview process for a Software Engineer at Justworks is structured to assess both technical skills and cultural fit within the company. It typically consists of several stages, each designed to evaluate different aspects of a candidate's qualifications and alignment with Justworks' values.

1. Initial Recruiter Call

The process begins with a 30-minute phone call with a recruiter. This conversation serves as an introduction to the company and the role, where the recruiter will discuss the job responsibilities, company culture, and benefits. Candidates can expect to answer questions about their background, technical skills, and motivations for applying. This is also an opportunity for candidates to ask questions about the company and the team they would be joining.

2. Technical Screening

Following the initial call, candidates will undergo a technical screening, which is typically conducted via video conferencing. This session focuses on assessing coding skills through a live coding exercise. Candidates may be asked to solve algorithmic problems or debug existing code, often using platforms like LeetCode or similar. The technical interviewer will evaluate the candidate's problem-solving approach, coding proficiency, and ability to articulate their thought process.

3. Onsite Interviews

Candidates who successfully pass the technical screening will be invited for onsite interviews, which may also be conducted virtually. This stage usually consists of multiple rounds, including: - Technical Interviews: These sessions delve deeper into specific technical skills relevant to the role, such as system design, architecture, and coding challenges. Candidates may be asked to design a system or solve complex problems on a whiteboard or shared document. - Behavioral Interviews: These interviews assess cultural fit and alignment with Justworks' core values. Candidates can expect questions that explore their teamwork, communication skills, and past experiences in collaborative environments. - Cross-Functional Interviews: Candidates may also meet with product managers or designers to evaluate their ability to work collaboratively across teams and understand the broader context of their work.

4. Final Interview

In some cases, there may be a final interview with senior leadership or team members. This round is often more conversational and focuses on the candidate's long-term goals, their vision for contributing to the team, and how they align with Justworks' mission and values.

Throughout the process, candidates should be prepared for potential ghosting after interviews, as some candidates have reported a lack of follow-up communication. It's advisable to send a thank-you email after interviews to express appreciation and reiterate interest in the position.

As you prepare for your interview, consider the types of questions that may arise in each of these stages.

Here are some tips to help you excel in your interview.

Understand the Interview Process

The interview process at Justworks typically involves multiple rounds, including a recruiter chat, technical screening, and onsite interviews. Be prepared for a mix of behavioral and technical questions, including coding challenges and system design discussions. Familiarize yourself with the structure of the interviews and the types of questions you might encounter, as this will help you feel more at ease during the process.

Prepare for Technical Challenges

Expect to face coding challenges that may include LeetCode-style questions, system design tasks, and debugging poorly written code. Brush up on your JavaScript/TypeScript skills, as these are crucial for the role. Practice coding problems that require you to think critically and solve complex issues efficiently. Additionally, be ready to discuss your previous projects and how you approached technical challenges in those scenarios.

Emphasize Teamwork and Communication

Justworks values teamwork and effective communication. During your interviews, highlight your ability to collaborate with cross-functional teams, including product managers and designers. Share examples of how you have successfully worked with others to achieve common goals, and demonstrate your openness to feedback and new ideas. This will show that you align with the company’s culture and values.

Showcase Your Problem-Solving Skills

The company looks for candidates who can apply good judgment and resourcefulness in their work. Be prepared to discuss how you approach problem-solving, especially in complex situations. Use the STAR method (Situation, Task, Action, Result) to structure your responses, and provide specific examples of how you have navigated challenges in your previous roles.

Align with Company Values

Familiarize yourself with Justworks' core values, known as COGIS: Camaraderie, Openness, Grit, Integrity, and Simplicity. Reflect on how these values resonate with your own work ethic and experiences. Be ready to discuss how you embody these values in your professional life, as this will demonstrate your fit within the company culture.

Be Prepared for Ghosting

Some candidates have reported experiences of being ghosted after interviews. While this can be frustrating, it’s important to remain professional and proactive. If you don’t hear back within a reasonable timeframe, consider sending a polite follow-up email to inquire about your application status. This shows your continued interest in the position and keeps the lines of communication open.

Ask Insightful Questions

At the end of your interviews, you will likely have the opportunity to ask questions. Use this time to inquire about the team dynamics, the company’s approach to professional development, and how success is measured in the role. This not only demonstrates your interest in the position but also helps you assess if Justworks is the right fit for you.

By following these tips and preparing thoroughly, you can approach your interview with confidence and increase your chances of success at Justworks. Good luck!

In this section, we’ll review the various interview questions that might be asked during a Software Engineer interview at Justworks. The interview process will likely assess your technical skills, problem-solving abilities, and cultural fit within the company. Be prepared to discuss your experience with frontend development, system design, and collaboration with cross-functional teams.

Technical Skills

1. Can you explain the difference between JavaScript and TypeScript?

Understanding the nuances between these two languages is crucial for a role focused on frontend development.

How to Answer

Discuss the key differences, such as TypeScript being a superset of JavaScript that adds static typing, which can help catch errors at compile time.

Example

"JavaScript is a dynamic, interpreted language, while TypeScript is a statically typed superset of JavaScript. TypeScript allows for type annotations, which can help catch errors during development rather than at runtime, making it easier to maintain large codebases."

2. Describe a challenging bug you encountered in a project and how you resolved it.

This question assesses your debugging skills and problem-solving approach.

How to Answer

Provide a specific example, detailing the steps you took to identify and fix the bug, and what you learned from the experience.

Example

"I once faced a bug where a component was not rendering correctly due to a state management issue. I used console logging to trace the state changes and discovered that the state was being mutated directly. I refactored the code to use immutable state updates, which resolved the issue and improved the component's performance."

3. How do you ensure the performance and scalability of a web application?

This question evaluates your understanding of best practices in web development.

How to Answer

Discuss techniques such as code splitting, lazy loading, and optimizing API calls to enhance performance and scalability.

Example

"I ensure performance by implementing code splitting and lazy loading to reduce initial load times. Additionally, I optimize API calls by batching requests and using caching strategies to minimize server load and improve response times."

4. Can you walk us through your process for designing a new feature?

This question gauges your design thinking and project management skills.

How to Answer

Outline your approach, from gathering requirements to prototyping and testing.

Example

"When designing a new feature, I start by gathering requirements from stakeholders and users. I then create wireframes and prototypes to visualize the feature. After that, I collaborate with the team to implement the feature, followed by thorough testing to ensure it meets the requirements before deployment."

5. What is your experience with version control systems, particularly Git?

This question assesses your familiarity with essential tools for collaboration.

How to Answer

Discuss your experience with Git commands, branching strategies, and collaboration workflows.

Example

"I have extensive experience using Git for version control. I regularly use branching strategies like Git Flow to manage features and releases. I also conduct code reviews through pull requests to ensure code quality and facilitate team collaboration."

System Design

1. How would you design a scalable web application?

This question tests your system design skills and understanding of architecture.

How to Answer

Discuss key components such as load balancing, microservices, and database design.

Example

"I would design a scalable web application by using a microservices architecture to separate concerns and allow for independent scaling. I would implement load balancers to distribute traffic evenly and use a cloud-based database solution that can scale horizontally as needed."

2. Describe how you would implement authentication and authorization in a web application.

This question evaluates your knowledge of security practices.

How to Answer

Explain the concepts of authentication and authorization, and discuss methods like OAuth or JWT.

Example

"I would implement authentication using OAuth for third-party logins and JWT for session management. For authorization, I would define roles and permissions within the application to control access to different resources based on user roles."

3. What strategies would you use to handle API rate limiting?

This question assesses your understanding of API management and user experience.

How to Answer

Discuss techniques such as exponential backoff, caching, and user notifications.

Example

"I would implement rate limiting on the server side to control the number of requests a user can make. Additionally, I would use exponential backoff for retries and cache responses to reduce the load on the API. Users would be notified when they approach their limits to improve their experience."

4. How do you approach testing in your development process?

This question evaluates your commitment to quality assurance.

How to Answer

Discuss your experience with unit testing, integration testing, and automated testing frameworks.

Example

"I prioritize testing by writing unit tests for individual components and integration tests for interactions between components. I also use automated testing frameworks like Jest and Cypress to ensure that my code is reliable and to catch regressions early in the development process."

5. Can you explain the concept of RESTful APIs and how you would design one?

This question tests your understanding of API design principles.

How to Answer

Discuss the principles of REST and how you would structure endpoints and resources.

Example

"RESTful APIs are based on stateless communication and use standard HTTP methods. I would design an API by defining resources and their relationships, using appropriate HTTP methods for CRUD operations, and ensuring that the API is well-documented for ease of use."

Behavioral Questions

1. Describe a time when you had to work with a difficult team member. How did you handle it?

This question assesses your interpersonal skills and conflict resolution abilities.

How to Answer

Provide a specific example, focusing on your approach to communication and collaboration.

Example

"I once worked with a team member who was resistant to feedback. I scheduled a one-on-one meeting to discuss our project and actively listened to their concerns. By fostering open communication, we were able to find common ground and improve our collaboration."

2. How do you prioritize tasks when working on multiple projects?

This question evaluates your time management and organizational skills.

How to Answer

Discuss your approach to prioritization, such as using tools or frameworks to manage tasks.

Example

"I prioritize tasks by assessing their impact and urgency. I use tools like Trello to organize my workload and regularly review my priorities with my team to ensure alignment with project goals."

3. What motivates you to perform well in your job?

This question gauges your intrinsic motivation and alignment with company values.

How to Answer

Discuss what drives you, such as personal growth, team success, or the impact of your work.

Example

"I am motivated by the opportunity to solve complex problems and contribute to a team's success. I find fulfillment in seeing my work positively impact users and the business."

4. How do you handle tight deadlines and pressure?

This question assesses your ability to work under stress.

How to Answer

Discuss your strategies for managing stress and maintaining productivity.

Example

"When faced with tight deadlines, I break down tasks into manageable chunks and focus on delivering the most critical features first. I also communicate with my team to ensure we are aligned and can support each other during high-pressure situations."

5. Can you give an example of how you have contributed to a positive team culture?

This question evaluates your teamwork and leadership skills.

How to Answer

Provide a specific example of how you fostered collaboration and support within your team.

Example

"I initiated regular team-building activities and encouraged open feedback sessions to create a supportive environment. This helped build trust among team members and improved our overall collaboration and productivity."