Citadel Securities Software Engineer Interview Questions
& Process
Real candidates share what happened, how many rounds they had,
and how the experience turned out.
Based on 93 interview experiences · FREE TO READ
Candidate interview experiences
First-hand accounts from people who interviewed at Citadel Securities.
Citadel Securities
Software Engineer
Entry Difficult Positive experience No offer 1 round
Interview process
Technical screen
Interview formats
Coding
The interview process overall was good. I've successfully completed the initial round, which involved a problem-solving question on HackerRank. The task was to optimize given code from O(n^2) to O(n) complexity. The specific problem was related to the 'Best Time to Buy or Sell Stock', a problem I've encountered on LeetCode before. I'm awaiting feedback from the hiring team within a week after submitting my solution.
Confirmed questions1 question
- The overall interview was good. I've just cleared the first round of the interview, which was a problem-solving question on HackerRank to optimize the given code from o(n^2) to o(n). The problem is based on: "Best Time to Buy or Sell Stock" which I already solved in LeetCode. Once I submit it, I will get the feedback from the hiring team in a week.
Citadel Securities
Software Engineer
Intern Difficult Neutral experience No offer 5 rounds
Interview process
Technical screen Group
Interview formats
Technical Coding Behavioral
There are about 4-5 technical interviews with engineers, then a team matching process. For internships, the team matching is for either Citadel or Securities. The technical interviews are similar to LeetCode problems. Team matching interviews can differ; some include technical questions, while others focus on assessing culture fit.
Confirmed questions3 questions
- Questions about string formatting
- Questions on recursive backtracking
- Questions about data structures
Citadel Securities
Software Engineer
Mid Average Positive experience No offer 4 rounds
Interview process
Technical screen Technical screen Technical screen Panel Background check
Interview formats
Technical Behavioral
They asked C++ technical questions about system programming and multithreading. The first interview was like "what do you know about C++14-17? what else do you know? and what else?" with explanations of how it all works. Then there was a block of 4 interviews, 3 were technical and the last one was behavioural. I am waiting for feedback for 2 weeks, they need time.
Confirmed questions2 questions
- Can you explain the inner workings of std::unordered_map?
- Could you give an example of how to use std::unordered_map?
Citadel Securities Software Engineer Interview Questions
Quoted word for word from Citadel Securities interview reports.
“What is the difference between concurrent systems and multi-core systems?”
Read reports →“Can you determine if a triangle formed by three given coordinates lies within those coordinates?”
Read reports →“Can you identify unique words in an array, given that you can rearrange the letters within those words?”
Read reports →“Could you design a random generator that takes a list of probabilities as input?”
Read reports →“Could you give an example of how to use std::unordered_map?”
Read report →“Can you explain how atomic types behave in C++?”
Read report →“Could you explain pre-order and post-order traversals for a tree?”
Read report →“How would you rotate a matrix to transform an input matrix into a target matrix?”
Read report →“Can you tell me about std::any and how it's implemented internally?”
Read report →Formats, difficulty and experience
Across all 93 Citadel Securities interview reports.