Live coding interviews are an effective way to identify qualified engineering candidates for technical roles. While they provide a highly realistic job simulation experience compared to traditional interviews, live coding interviews can be stressful for candidates and time-consuming for hiring teams—so it’s best to conduct these interviews on a platform designed specifically for technical hiring to reduce friction for all parties. Interviewers can also make the most of these interviews by preparing ahead of time, using a structured interview format with questions that build on each other, and assessing candidates using a rubric.
Live coding interviews have elevated how companies do technical hiring, but they’re not without their own set of challenges and considerations. If you, as an engineering manager, tech lead, or interviewer, are grappling with how to conduct these interviews efficiently, you’re not alone. Most engineering teams recognize the importance of these interviews, but spend far too much time on preparing for, conducting, and debriefing them—and, even then, may struggle to identify qualified candidates. And the consequences can be steep: a wrong hiring decision isn’t just about a mismatch of skills—it’s about the time, resources, and opportunities lost.
This article serves as a comprehensive guide to demystifying the process and offering actionable insights to enhance how you conduct live coding interviews. By the end of this piece, you’ll have a clearer understanding and a roadmap to conduct live coding interviews that are rigorous, fair, and effective.
Leveraging insights from thousands of interviews conducted on CodeSignal, the leading technical interview and assessment platform, this article offers a blend of industry knowledge and practical advice. CodeSignal has been at the forefront of technical hiring since 2014, understanding the nuances of what makes an interview successful and the pitfalls to avoid. Drawing upon this wealth of knowledge, we’re here to guide you on the path to more effective, streamlined, and impactful live coding interviews.
Jump to a section:
- What is a live coding interview?
- Benefits and challenges of live coding interviews
- How to prepare to conduct a live coding interview
- How to conduct a live coding interview
- Assessing the candidate after a live coding interview
- Final thoughts
What is a live coding interview?
A live coding interview is a common method that companies employ to assess the technical skills and problem-solving abilities of software developers and engineers. During this type of interview, candidates are asked to write, debug, or enhance code in real-time, typically via an online coding environment, while interviewers watch and ask clarifying questions—and, in some platforms, even engage in pair programming. This hands-on approach allows interviewers to gauge not only a developer’s technical prowess but also their thought processes, problem-solving strategies, and ability to handle pressure, empowering them to identify developers and engineers who will be most impactful on their team.
For engineering managers and those who conduct technical interviews, it’s essential to understand the specific benefits and uses of a live coding interview. These interviews offer a more practical and accurate snapshot of a developer’s coding capabilities than a traditional question-and-answer format might. Moreover, they allow companies to better match developers with roles that fit their expertise and to ensure that potential hires can tackle the challenges they’ll face on the job.
Benefits and challenges of live coding interviews
Live coding interviews, while a significant shift from traditional interviewing methods, have today become a mainstay in the tech industry’s hiring process. These sessions aim to capture a developer’s coding skills and approach to creative problem-solving in real-time. However, like any interviewing method, live coding interviews come with their set of advantages and disadvantages.
- Assessing creativity and technical skill: Unlike the typical whiteboard exercises or theoretical questions that dominated technical interviews in the past, live coding sessions allow companies to observe a developer’s creativity in a realistic development environment. They offer a clearer insight into how a candidate thinks, codes, and problem-solves on the spot.
- Authentic work simulation: Traditional whiteboard problems often receive criticism for not accurately representing the work developers do daily. Live coding interviews are more in line with the actual challenges developers face, providing a genuine test of their technical and job-relevant skills. Interviewers can add a virtual whiteboarding component to live coding interviews to assess system design and similar skills.
- Dynamic and flexible environment: Interviewers can adapt the problems, introduce new constraints, and ask pointed follow-up questions as they observe the developer’s approach. This dynamic setting makes for a more comprehensive evaluation than static questions might.
- Stress-inducing situation: One of the most prominent criticisms of live coding interviews is the stress they impose on candidates. Coding under the watchful eyes of interviewers can be intimidating, potentially affecting performance and not truly reflecting a candidate’s capabilities in a relaxed environment.
- Risk of subjectivity and bias: An interviewer’s perception could be swayed by minor errors that a developer might commit under pressure, even if they’re well-qualified. Or, question wording may include culturally-specific references that hurt the performance of candidates with the requisite technical skills. This could lead to overlooking otherwise exceptional candidates.
- Logistical challenges: Setting up a smooth live coding environment requires a stable internet connection and sometimes a specific setup, which can be time-consuming or might face technical glitches.
Understanding these pros and cons allows interviewers and engineering managers to make informed decisions about how, when, and why to deploy live coding interviews in their hiring processes.
How to prepare to conduct a live coding interview
The best way to prepare to conduct a live coding interview is to be thoroughly familiar with the expectations of the role you’re hiring for and the challenges the potential candidate may face on the job. This means having a clear understanding of the core knowledge, skills, abilities, and other characteristics—or KSAOs, which IO Psychologists use to conduct a job analysis to align job descriptions and hiring practices to the requirements of a role. For software developers and engineers, this will include core computer science knowledge and skills and, for some roles, specific programming languages (Java, Ruby, etc.), tools, and frameworks.
Firstly, it’s crucial to make use of a technical hiring platform conducive to the interview. An integrated development environment (IDE) or an online code editor that you and the candidate are comfortable with can ensure the coding interview process allows interviewers to effectively assess candidates’ job-relevant skills. Familiarize yourself with the tools, and make sure there’s an easy way for the candidate to access and use them without any technical glitches.
Secondly, get clear on the role-relevant concepts and skills in computer science that you intend to evaluate. Topics like algorithms and data structures, including arrays, linked lists, and graph traversal, are common areas of focus. Create a structured interview made up of coding challenges that are relevant to the role and that allow candidates to showcase their understanding and application of these concepts. Problems like finding anagrams or designing a specific algorithm can be insightful.
To make the interview more realistic, use a series of coding questions that build on each other, increasing in complexity as the interview progresses; these are also known as progressive questions. Progressive questions effectively simulate real development work in the interview environment, allowing interviewers to gain a strong signal of candidates’ job-relevant skills.
Remember, the goal of a live coding interview or technical interview is not just to test the candidate’s knowledge but also to see how they approach and solve problems in real-time. Thus, having a balance of fundamental and challenging problems will give you a comprehensive view of the candidate’s skills and potential.
Choosing a live coding interview platform
When selecting a platform for live coding interviews, it’s essential to consider the needs of software engineers and the specific requirements of the interviewing process. An ideal coding interview platform should offer real-time collaboration features, allowing both the interviewer and the candidate to simultaneously view, write, and edit code. This real-time interaction is crucial in understanding a candidate’s thought process and digging deeper into their problem-solving abilities. Other features that enhance the coding experience include syntax highlighting and autocomplete, which mimic the environment software engineers are accustomed to and allow them to focus on more complex skills during the interview.
Among the plethora of assessment tools available, CodeSignal stands out as a tech recruiting platform tailored for enterprise needs. It not only encompasses all the aforementioned features but also offers a comprehensive environment that facilitates the engineering interview process. With its live interviewing solution that includes full terminal access, live front-end and mobile application preview, syntax highlighting, autocomplete, and more, CodeSignal provides a seamless experience for both interviewers and candidates.
How to conduct a live coding interview
Conducting a live coding interview requires a blend of preparation, knowledge of the skills required for the role, and the right interviewing tools. While many organizations initially leaned towards familiar platforms like Zoom or Microsoft Teams for live interviews, it’s essential to recognize that these tools were not designed with technical hiring in mind. Conducting a technical interview on such platforms can lead to a subpar experience, both for the interviewer and the candidate. Instead, hiring teams will see significantly better results by using platforms built specifically for technical interviews. These platforms typically offer features that allow both the candidate and the interviewer to edit and run code in real-time, streamlining the interview process and ensuring smooth collaboration.
Before the interview, ensure that all technical settings are in place, and both you and the candidate have access to the platform. Begin the interview with a brief introduction and set clear expectations about what the technical interview will entail. This helps put the candidate at ease and provides clarity on how the session will proceed. Then, present the coding problem and let the candidate walk you through their thought process and approach. If you’re using progressive questions, you’ll start first with simpler challenges to help the candidate “warm up,” then build toward more complex requirements and problems.
During the interview, focus on understanding the candidate’s approach rather than just the final solution. This will give you insights into their problem-solving skills, adaptability, and depth of knowledge. A successful live coding interview is one where the candidate has had the opportunity to showcase their skills in an environment that mimics real-world scenarios, and where the hiring team can confidently assess a candidate’s fit for the role.
Assessing the candidate after a live coding interview
One of the primary goals of a live coding interview is to assess a candidate’s coding skills and problem-solving abilities in real-time. To achieve this, interviewers should not just focus on whether the final code works, but also on the journey the candidate takes to arrive at the solution. How does the candidate approach the problem? Do they break it down logically, or do they rush into coding without a clear strategy? Evaluating their problem-solving methods offers valuable insights into how they might tackle challenges on the job. Additionally, the quality of the code they produce—its readability, efficiency, and structure—speaks volumes about their expertise and attention to detail.
Given the subjective nature of such assessments, it’s crucial to have a standardized approach to evaluating candidate performance to ensure fairness and consistency. Using a rubric can be instrumental in this regard. A well-defined rubric allows interviewers to evaluate a candidate’s skills objectively, reducing biases and providing a clearer picture of the candidate’s strengths and areas for improvement. By focusing on quantifiable abilities, like code quality, efficiency, and problem-solving strategies, interviewers can make more informed decisions and ensure that evaluation criteria are consistent across multiple candidates.
Live coding interviews have carved a unique space in the tech hiring landscape, offering a hands-on approach to evaluate developers’ and engineers’ technical skills and problem-solving strategies. This method has clear advantages, such as presenting an authentic picture of a developer’s job-relevant knowledge and skills. However, hiring teams should take steps to help candidates know what to expect for these interviews to reduce candidates’ stress.
To conduct these interviews efficiently, interviewers must be well-prepared and familiar with the job-relevant skills required of the role they’re interviewing for. Choosing the right platform is equally vital; teams should use tech hiring tools designed specifically for technical interviews and assessments. Lastly, an objective assessment of the candidate after the interview, assisted by a structured rubric, ensures fairer and more consistent evaluations, providing a holistic understanding of the candidate’s abilities.
CodeSignal Interview is an advanced integrated development environment (IDE) with live collaboration, including video and audio calling. It provides candidates the coding tools they actually use on the job with a terminal, filesystem, and live frontend preview—all in one window, and allows interviewers to work alongside candidates.
Ready to learn more about leveling up your live coding interviews? Schedule a call with one of CodeSignal’s tech hiring experts today.