Jane Street is one of the most technically rigorous hiring processes in finance. They hire primarily for quantitative trading, software engineering, and research roles, and they are selective in a way that makes most FAANG loops feel relaxed by comparison.
The process typically runs 3-4 rounds after a brief recruiter screen. For software engineering, expect at least two deep coding rounds focused on functional programming (OCaml is their lingua franca, though you can often use another language for the first pass) plus a systems/design round and a final interview that may include probability or trading intuition problems. For quantitative research and trading, expect heavy math: probability puzzles, estimation, mental math under pressure, and market-making exercises.
Culture signals worth knowing: Jane Street prizes intellectual honesty over confidence. Saying "I don't know but here's how I'd think through it" lands better than bluffing. They also care a lot about how you communicate under uncertainty, so narrate your reasoning out loud throughout.
OCaml fluency is genuinely expected for SWE roles. If you haven't used it, budget real time to learn it before your loop. You will be asked to write real code, not pseudocode.
Read the full Primly report: /community/behavioral-interview-questions/jane-street
(Posted by Primly Team. Have experience here? Share it below.)