Jane Street Interview Experiences

11 results

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  Exchange Arbitrage and Quote ThroughputJane Street · Software Engineer · Intern · Technical Screen · Aug 2026

  It was a low-level-design problem. Core problem: An Exchange Arbitrage System for stocks. Assume there are multiple exchanges, each with a market feed continuously publishing bid and ask prices for different instruments or stocks. Design and implement an arbitrage strategy. The example gave AAPL on exchange A a bid of \$1.00 and an ask of \$1.10, while exchange B had a bid of \$0.90 and an ask of…

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  Recursive Arithmetic with Invalid Intermediate ResultsJane Street · Software Engineer · Intern · Technical Screen · Aug 2026

  An algorithms/LeetCode-oriented question. Problem description: Given a string expression, evaluate it and output the arithmetic result. Restrictions and constraints: Only positive integers are supported. Intermediate-state validation: At any stage of the calculation, if a negative number appears (for example, an intermediate result below 0) or a non-integer appears (for example, division that pro…

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  Jane Street Quantitative Analyst interview: probability games before superdayJane Street · Quantitative Analyst · Technical Screen · Jul 2026

  Rejected

  I had several Zoom interviews, with three technical rounds before a superday. The questions were built around games presented by the interviewers and relied heavily on probability and game thinking. The early games were more straightforward and closer to deterministic setups. Later rounds brought more randomness and more game theory. In the more open-ended game rounds, I needed to optimize outcom…

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  Jane Street Quantitative Analyst interview: probability rounds and nervesJane Street · Quantitative Analyst · Technical Screen · Jul 2026

  After applying online, I had a resume screen and a first technical round. It was my first quant interview, and I was nervous enough that I did not answer as smoothly as I wanted. I did not move past that round. I later entered through a program that sent me directly to interviews. There were two 45-minute Zoom technical rounds. The first was clearly easier than the second, and the interviewers we…

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  Jane Street Software Engineer interview: final onsite mattered mostJane Street · Software Engineer · Onsite · Jul 2026

  I started with a virtual round and then moved to an onsite. The questions blended coding with system-design-style work, but they emphasized real-world systems more than academic exercises. By the onsite, it was clear that this was the most important stage and that the bar was highest there. I did not perform well enough in that final stage to move forward. The process was intense, and my main tak…

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  Jane Street Quantitative Analyst interview experience: probability progressionJane Street · Quantitative Analyst · Jun 2026

  I went through math-focused interviews that started with easier questions and became harder. The rounds centered on probability. Early questions established the fundamentals, then the difficulty increased. Each round also began with a behavioral check-in, which set expectations before the technical work. In a similar run, I had three phone interviews along the same probability track. The first co…

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  A Stream-Transformer Coding Question from the Phone ScreenJane Street · Software Engineer · New Grad · Technical Screen · Feb 2026

  This is an old one — sharing a question from my campus recruiting interview back in the day. Given a set of M codes and N timestamps, the ideal shape for the data is an N x M matrix, where the rows are sorted by time and the columns are sorted by the code's lexicographic order. But not every code has data at every timestamp. You're given a stream of std::vector >,…

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  Onsite System Design on Orderbooks, Rejected Before the Coding RoundJane Street · Software Engineer · Onsite · Dec 2025

  Rejected

  Real-time report from the London office. The OA and first-round phone interview are already covered elsewhere on the forum, so this is just filling in the details on R2 and the onsite. R2: a coding interview (sort trade) — this one's also up on Glassdoor. Compared to a typical algorithm question, the setup was closer to "how would you implement this feature in a trading system," testing your logi…

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  Three Phone Rounds, All Game TheoryJane Street · Quantitative Trading · Intern · Technical Screen · Dec 2025

  I'll share my experience with the three phone-interview rounds for a quant trading internship at Jane Street's NYC office. Jane Street likes to test with games — no math brainteasers, no algorithms, none of that standard stuff. You don't need to answer fast either; taking a minute or two to think or calculate before giving an answer is completely fine. Round 1: two questions, both original questi…

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  Maximizing Reward as Pixels Reveal One Row at a TimeJane Street · Software Engineer · Technical Screen · Sep 2025

  The interview was about solving an actual problem. The setup was an image classification problem using the FashionMNIST dataset. The model (a plain CNN) and the training code were already written, and the task was to modify it question by question from there; the environment they gave me was a Jupyter notebook (.ipynb). There were mainly two parts. After understanding the code (there wasn't much…

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  OA Then a Phone Screen With Palindrome and Dice-Game Brain TeasersJane Street · Software Engineer · Technical Screen · Sep 2025

  I submitted my resume and got the OA email the next day. The problem was one that's already floating around the forum: using Excel to calculate a haircut, plus general Excel formula usage. Same numbers as the version posted on the forum, nothing changed. My suggestion if you're filling in the spreadsheet and need to use data from the problem's own table: use a reference, not copy-paste. The probl…