// quant-finance
Probability, brainteasers, mental math, and low-latency systems — how trading firms actually interview.
6 min read A breakdown of Tower Research Capital’s engineering loop, the C++ and systems questions it leans on, and what the multi-desk Super Day means for candidates. Read article
7 min read A breakdown of XTX Markets’ online assessment, technical call, and London onsite, and what the firm expects from quant researchers and developers. Read article
7 min read DRW’s interview runs from a quantitative take-home through a probability call to an in-person Superday with a live trading simulation. Read article
7 min read The IMC Trading interview splits into a trader track built on mental math and market-making games and an engineer track built on low-level C++ and a matching-engine build. Read article
6 min read The reroll game, HH versus HT waiting times, the coupon collector, Bayes, and making a market, with the reasoning trading firms actually grade. Read article
6 min read Jane Street’s software engineer loop is a remote coding screen and a full day of collaborative rounds, with no brainteasers, no separate system-design round, and no OCaml requirement. Read article
8 min read The lock-free single-producer queue is the anchor of the quant developer onsite, and what it really tests is the C++ memory model and cache behavior, not data structures. Read article
6 min read A walk through the mock-market rounds, expected-value bets, and mental-math screens that firms like Optiver, SIG, and Jane Street use to hire traders. Read article
6 min read The probability facts and reasoning patterns that come up most in trading interviews, and the setups that trip people up. Read article
6 min read A look at D. E. Shaw’s quant and developer interview loops, the probability and coding questions they ask, and how they grade your reasoning. Read article
5 min read Optiver’s trader interview runs from a timed math test to a market-making game, and each round is measuring something specific about how you handle pressure and incomplete information. Read article
6 min read Two Sigma runs separate engineering and quant-research loops, and each one fails candidates for a different reason. Read article
6 min read Citadel the hedge fund and Citadel Securities the market maker are separate companies with separate loops, and prepping for one won’t carry you through the other. Read article
6 min read How Jane Street builds quant and trader pay in 2026, why the bonus dwarfs the base, and what first-year and senior totals really look like. Read article
5 min read The order-book question is simple to state and brutal in the follow-ups. Here’s what trading firms actually look for. Read article
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