Quant trader, researcher or developer: how the interviews differ
Updated 1 October 2026 · 2 min read
The three roles share a vocabulary and often a building, but their interviews test different things. Preparing for the wrong one is the most common waste of preparation time – a researcher candidate drilling 80 in 8, or a trader candidate revising gradient boosting.
Quant trader
Traders make decisions in real time with money at stake, so the interviews test speed, probability intuition and judgement under risk.
- Online tests: mental arithmetic, sequences, quick probability – see the screening tests.
- Interviews: probability and expected value aloud, games and decision theory, betting and sizing (Kelly and risk of ruin).
- Trading games: making markets and managing a position – see make me a market.
- At options desks, also options and the Greeks.
Coding is usually light or absent for pure trading roles. Depth in statistics matters less than speed and clean reasoning.
Quant researcher
Researchers find and validate signals, so the interviews test statistical depth and research judgement – whether you can tell a real effect from noise.
- Probability and statistics in depth: estimation, testing, multiple testing.
- Regression: assumptions, what breaks, and the questions firms actually ask.
- Machine learning, with a focus on validation – especially why k-fold fails on financial data.
- An open-ended research case: see a method for research cases.
- Coding in Python for data work, sometimes a take-home exercise.
Mental arithmetic speed matters little here; being able to derive, question assumptions and explain trade-offs matters a great deal.
Quant developer
Developers build the trading systems, so the interviews look like strong software engineering interviews with a performance slant.
- Online coding tests on algorithms and data structures.
- Interviews on complexity, C++ or Python, and systems: caches, concurrency, networking and latency.
- For low-latency roles, how an order book is engineered.
- Some probability, particularly at firms that blur the line with algorithm development.
Side by side
- Speed of arithmetic: essential for traders, minor for researchers and developers.
- Probability: essential for traders, essential for researchers, useful for developers.
- Statistics and regression: useful for traders, essential for researchers, minor for developers.
- Coding: minor for most trader roles, important for researchers, essential for developers.
- Market intuition and risk: essential for traders, useful for researchers, minor for developers.
Tip
If you are unsure which role you want, start with probability – it is the one subject all three test – and let your results in the screening tests and the question bank tell you where you are strongest.
Study paths
QuantMax groups the curriculum into a path for each role: trading and market making, quantitative research, quantitative development and derivatives and options. Each orders its topics the way the interviews test them.
Read next
Where a firm is named, this describes what candidates publicly report, not information from the firm. Processes change by year, role and office. QuantMax is not affiliated with any firm named here.