Cracking the xai Software Engineer Interview: Multi-threading Debugging Insights

Software Engineering
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xai | Software Engineer | Interview Experience

Interview Date: Not specified
Result: Not specified
Difficulty: Not specified

Interview Process

I applied for a network-related infrastructure position, and a coordinator contacted me. The company has a high workload, starting at 60 hours a week, with 80-100 hours not being uncommon.

Initially, the network team mentioned that the hiring manager was in Ireland. I inquired about interview times at 4 AM or 6 AM, which was a new experience for me. The day before the interview, I was informed that the hiring committee was canceled, but the coordinator quickly arranged a new time with the supercomputing team and provided a tip for the 15-minute video call:

For the 15-minute video call, you can expect to discuss your background, experience, relevant technical knowledge, as well as a coding question.

I thought 15 minutes was too short to cover my background and have time for coding, but the interview proceeded differently than expected.

The interviewer was a Chinese gentleman who provided little feedback throughout the process. After a brief self-introduction, he asked me to describe my background. I started to explain my current company, but he interrupted me to “focus on recent” experiences and asked about challenges in my projects. After a brief discussion, he moved on to the coding question.

Technical Questions

  1. Bank Account Multi-threading Debugging (Multithreading, Concurrency)
    The task involved debugging a multithreaded program for depositing money into a bank account. The provided code had the following issues:
    • Bug #1: Race condition in the deposit() method due to simultaneous access by multiple threads.
    • Bug #2: Lack of thread safety mechanisms, as there were no locks to prevent concurrent access, leading to potential data corruption.

Tips & Insights

The coding question tested my ability to identify race conditions and implement thread safety. Although the question was straightforward, it required proficiency to recognize issues and implement solutions quickly. After the coding part, I asked about the work hours and received a confirmation of 60-80 hours per week, which was concerning. The interviewer seemed reluctant to engage further, indicating a possible fatigue from the workload.