I applied through a staffing agency. The process took 1 week. I interviewed at Citadel Securities in Jan 2020
Interview
I was put in touch with the company via a headhunter. The interview was over coderpad and the phone. The interviewer asked questions about bash, networking, and C++. We did not get around to discussing math/stats.
Interview questions [1]
Question 1
Given a struct A containing only a single integer data member, how would you write a hash function for an std::unordered_set<A> in C++?
I applied through a recruiter. I interviewed at Citadel Securities (London, England)
Interview
5 rounds in total, starting with hr, hiring manager, potential team. Fairly technical: manager round was a theory quiz covering computer fundamentals, the rest of the rounds were coding rounds
Interview questions [1]
Question 1
Write a matching engine, write ring buffer, lock free queue
I applied through a recruiter. I interviewed at Citadel Securities in Mar 2026
Interview
I had a intro phone call and then a technical. The technical was a leetcode style question. They wanted to know more about what team I would be best fit for.
I applied online. The process took 1 week. I interviewed at Citadel Securities (Gurgaon, Haryana) in Oct 2025
Interview
I applied online for the junion C++ quantitative developer role. After one week, I got intital OA which was a C++ hackerrank. The problem required to optimize an already given function.
Interview questions [1]
Question 1
The problem required to optimize an already given function.