A common point of confusion clears a lot up: a large multi-strategy platform often contains both a hedge fund and a separate market-making business, each with its own hiring process. Citadel and Citadel Securities are the best-known example of exactly this split. Both sides typically run an early online assessment followed by technical rounds, and both prize precise quantitative reasoning - but you should tailor your prep to the specific entity and role.
What the interviews test
Across both, expect probability and statistics worked rigorously, brainteasers that reward structured reasoning, and - for technical tracks - programming and data structures. The emphasis differs by track:
| Track | Leans on |
|---|---|
| Trading | Probability, expected value, mental math, brainteasers |
| Quant research | Deeper statistics and probability, modelling |
| Engineering / quant dev | Coding, data structures, systems |
Key insight. What unites every track is a high bar for clear, precise reasoning rather than memorised tricks. These interviewers would rather watch you derive a result cleanly than hear a formula you can't justify.
How to prepare
- Build broad probability and statistics fluency - the common core across tracks.
- Drill brainteasers and practise explaining your reasoning aloud.
- For technical tracks, keep your programming and DSA sharp.
- Simulate the timed screen with the Probability OA.
When you are ready, work the question set for this format. For a neighbouring research-and-coding format, see the data-driven research guide.