GumGum Software Engineer Interview Questions
& Process

The interview process started with a 45-minute Zoom call with a recruiter named Jeff to discuss my background and the role. This was followed by a one-hour Zoom interview with the Hiring Manager, focusing on behavioral questions and requiring a strict understanding of the ad tech domain. After positive feedback from the HM, I proceeded to a coding round. In this round, I was given a coding problem on Hackerrank that involved strings and math, with many test cases for large inputs that were not shared. The task seemed to involve low-level character to integer conversions for handling large values, which I found unusual for a senior developer role. I used Java and the Streams API, and while my concise code passed some test cases, larger ones failed due to my approach not involving the expected conversions. This entire process took about 3 hours. Subsequently, the recruiter became unresponsive.

I first chatted with the hiring manager for a phone screen, which went pretty well. Before I went onsite, he told me I'd get a Hackerrank challenge. It had 2 coding problems and some multiple-choice questions, but he said to ignore the MCQs. The first coding problem was easy, mostly about OO concepts. The second problem wasn't super hard, but you'd only pass a few test cases if you just did the obvious stuff. They expect you to figure out 7 edge cases in under 50 minutes, and you can't even see the sample input. I thought that was unrealistic. I don't know if they could actually find someone for this startup in Santa Monica who could come up with those 7 test cases.

It was a pretty standard process. First, I chatted with a Product Manager about my resume, my interests, and some projects. Then, I had a phone interview where I had to code two LeetCode medium-level problems in a Google Doc. After that, I was invited for an onsite interview, which included four rounds. The company covered my travel and accommodation since I was coming from New York. The first onsite round was a presentation about a project I was heavily involved in, followed by questions about it. The next round was a pair programming session with a simple Java question, but the main focus was on writing JUnit tests. Then came a system design round, covering both high-level and low-level aspects. The final round was a casual chat with two engineers from the team. Overall, it was a good experience. My advice is to be confident and brush up on the basics. I wouldn't say it was tough, just stay calm.