I applied through a staffing agency. I interviewed at Citadel Securities in Apr 2020
Interview
The interviewer was very bad at defining the problem statement and couldn't give me good test cases. I didn't have a good understanding of the problem going into it. They was also not helpful when I asked clarifying questions. With all this, I made a mistake initially and instead of letting me figure out what's happening, they proceeded to dictate his solution to me. They seemed impatient in the sense that he wanted me to already "know" the answer before I had the time to think about it. They also jumped in several times in the middle of me debugging instead of letting me figure the bug out.
I think this has been the worst interview experience I've ever had. As someone who's been an interviewer, what I'm looking for in candidates is to see their line of thinking when approaching a problem. Candidates often make mistakes and seeing how they identify and fix their mistakes is also something that I would be looking at. To me, it seemed like the interviewer today was only interested in knowing whether I've already solved this problem on leetcode.
I applied through a recruiter. I interviewed at Citadel Securities (New York, NY)
Interview
The process was quite standard, but there was a big time gap between the OA and the interview. All rounds had both a background discussion and technicals. Technical rounds were with actual SWEs. They were pretty friendly, and more concerned with problem-solving than trivia or language depth.
Interview questions [1]
Question 1
OA was quite easy, 2 questions: first was lc medium, second was lc easy. First round was standard DSA question for an order book string problem. Second round was heavy C++ debugging.
I was reached by a recruiter, and I was later called for a personal interview which happened on zoom. This was for HK location. There was no online assessment test.
Interview questions [1]
Question 1
Implement queue using vector, no constraints were given. I did it but took some time - verdict - reject.
Also asked in depth about a project I've worked on and I am proud of. I spoke of the last project I had worked on, he seemed satisfied didn't ask a lot of cross questions.
Standard frontend exercise. Know your javascript and react. Be prepared to explain how you would optimize for performance.
Explain in depth how react renders and rerenders.
Handle real time data display.