The first interview was supposed to focus on DSA, but it shifted more toward system design. The interviewer joined about seven minutes late, and the problem statement he provided was unclear. It seemed like he mixed two different questions together. Based on the given statement, the correct solution was simply to maintain a map and return the latest value by topic—which even ChatGPT later confirmed. However, the interviewer was not willing to accept this approach and seemed to be expecting a pub/sub-style solution that didn’t align with the stated problem.
He also appeared unprepared and quite casual at the start of the interview. After some disagreement on the solution, he continued asking various scalability-related questions, an area in which I don’t yet have much experience. He seemed to be looking for immediate, hands-on expertise rather than a candidate who is capable and willing to learn, which was contrary to what HR had communicated.
For context, I come from a frontend background, have worked on backend on NodeJS in my early career, and applied for the full-stack role specifically because I am eager to learn and grow in that direction.