I like to ask candidates to design a basic video conferencing app. The prompt is: 'Design a video conferencing app that supports real-time video streaming, user authentication, and group calls. How would you structure it, and what considerations would you take into account for scalability, security, and handling real-time data?' This question is highly effective because it forces candidates to think about multiple layers of a real-world application-front-end, back-end, data handling, and security. It also helps me see how they approach challenges like real-time communication, user authentication, and scaling an app for multiple users. This type of question allows them to showcase both problem-solving and system design skills, which are crucial when building complex applications.
effective technical interview question I use to assess problem-solving skills in software developer candidates is: "Given a list of integers, write a function that returns the two numbers that add up to a specific target. If no such numbers exist, return an indication that there are none." This question encourages candidates to demonstrate their understanding of algorithms and data structures while allowing them to showcase their problem-solving approach. What makes this question particularly effective is its ability to reveal the candidate's thought process, coding style, and efficiency in problem-solving. Candidates often start by discussing their approach, which provides insight into their analytical skills and how they break down a problem. Additionally, it allows them to explain their reasoning and consider edge cases, such as negative numbers or duplicates. By observing how they optimize their solution-whether they choose a brute-force approach or implement a more efficient algorithm using a hash map-I can gauge their proficiency in coding as well as their ability to think critically and adapt. Overall, this question serves as a practical and revealing way to assess both technical skills and problem-solving capabilities.
Other than the technical skills, getting an idea of the analytical skills of the software developer is important. To understand that, a particular question that I had asked was: "Suppose you are working on improving our product, which was earlier built by another team of developers; now, the client is facing some issues. You do not have the resources to overhaul the product/service entirely. How would you approach this situation to both identify the root cause of the issue and devise a cost-effective solution?" This gave us an understanding of how critically and deeply the interviewee analyzes the problem, considering the restrictions around resources to come up with a solution.