Jane Street software engineering interview questions

The Process

Five stages, and not one of them is a system design round

01

20 to 30 minPhone call

Recruiter call

Lighter than most. There is no level to settle because the firm does not have levels, so this is mostly about which track you are on and how quickly you can interview.

Say which track you actually want.
Software, quantitative trading and research run different loops out of the same recruiting team, and moving between them later restarts the process.
Ask how many rounds you are being put through.
It varies by track and by office. Some candidates get two phone rounds before the final day, some get one, and nobody tells you unless you ask.
Do not negotiate a base number here.
Base sits in a narrow band and barely moves. The bonus is discretionary and decided at year end, so there is nothing to anchor on this early.

02

45 minVideo call

First technical screen

One problem, worked out loud with the interviewer. They will interrupt, offer hints and expect you to take them. Refusing help reads worse here than being stuck.

Ask for help on purpose, early.
Collaboration is scored directly. A candidate who reaches the answer alone in silence rates below one who talks through a wrong turn and takes a hint.
Think in values, not in variables.
The firm runs on OCaml. You will not be asked to write it, but you will be asked to reason about recursion, immutability and pattern matching.
Say the invariant before the code.
Stating what stays true at each step is the behaviour interviewers write up as strong. Jumping to an implementation is what stalls candidates.

03

45 minVideo callNo coding

Estimation and probability

Not a LeetCode round. Expected value, conditional probability and estimates you have to reason to rather than recall. Trading and research candidates also sit a timed mental arithmetic test and a market making game; software candidates usually do not.

Learn to be wrong out loud.
They want the structure of your estimate, not the number. Say your assumptions, give a range, then say which assumption you least trust.
The arithmetic test is speed, not maths.
Eight minutes of sequential addition, subtraction and percentages with no calculator. It is a trading track filter, and practice moves the score a lot.
Market making is about your spread.
You quote a two sided price on something silly, then get traded against and asked to requote. They are watching how you update, not whether you were right.

04

4 to 6 roundsOne dayIn person

The final day

Back to back technical rounds with no system design, no take home and no presentation. The same collaborative style as the screens, run by people you would sit next to.

Every round is a fresh start.
Interviewers write up independently and are not told how you did earlier. A bad round is survivable in a way it is not at most firms.
Bring your own language and know it cold.
You pick the language and they will push on its semantics. Mutable defaults, copy versus reference, how equality works. Fluency beats breadth.
Expect to be asked to change your answer.
Interviewers add a constraint late and watch what you keep. Candidates who defend the first design instead of reworking it lose the round.

05

2 to 5 daysNo committee

Decision and offer

Fast, because the people who interviewed you decide. No hiring committee, no calibration weeks later. The offer is a base plus a year end bonus nobody will put in writing.

The bonus is the offer.
Base is a narrow band. Everything that makes the number large is discretionary, decided at year end, and paid on firm and personal performance.
Ask what a typical first year paid.
They will not commit, but recruiters will describe ranges for people who joined at your stage. That is the only forward looking number you will get.
There is no counter offer ladder.
Levels do not exist, so you cannot be bumped a band to close the gap. Competing offers move the guaranteed first year component or nothing.

Levels and Pay

There are no levels here, and the bonus is the whole story

Pick a level to see how the package splits, what changes by city, and what the loop actually asks of you at that band.

New York

London

Hong Kong

Amsterdam

Level	Experience	Total comp
Software EngineerY1Yr 1	Out of college	~$375K
Software EngineerY3Yrs 2-5	2 to 5 yrs	~$525K
Software EngineerY6Yrs 6-8	6 to 8 yrs	~$775K
Software EngineerY9Yrs 9-12	9 to 12 yrs	~$1.05M
Software EngineerY13Yrs 13+	13+ yrs	~$1.5M

Hong Kong is shown in US dollars, which is how offers there are discussed.

Live Question Feed

What Jane Street is asking right now

26 questions · new ones added every 7 days

26 Verified

CODING

Build an evaluator for a small expression language with arithmetic, variables and let bindings, then add closures without mutating state.

The final day

45 min

Shared editor

Reported 7 times

Open

PROBABILITY

You roll a die until the first six. What is the expected sum of everything you rolled, including the six?

Locked

BEHAVIORAL

Tell me about a time you were stuck and had to decide between asking for help and pushing on alone.

Locked

CODING

Implement a persistent immutable list with constant time prepend, then explain what is shared between versions.

Locked

ESTIMATION

How many piano tuners are billing in New York this year, and which assumption would you check first?

Locked

MARKET MAKING

Make me a two sided market on the number of red cars you passed on the way in, then I will trade you.

Locked

CODING

Given trades with timestamps and prices, find the best profit from at most K non overlapping transactions.

Locked

PROBABILITY

Two players alternate flipping a fair coin. What is the probability the first player sees heads first?

Locked

BEHAVIORAL

Why Jane Street rather than a larger firm, and what would make you leave after two years?

Locked

25 more questions available

The exact questions Jane Street is asking this week, tagged by round and difficulty.

Unlock All 26 Questions

Each question stays in the bank for 14 days, so everything here was asked in the last 14 days. Candidates who see them first pass at 3.2 times the normal rate.

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The Unfair Advantage

Why this actually works

01

Real questions, not guesses

Collected from engineers who sat the loop, then cross validated against other intel sources.

02

Fresh every week

The database updates every 7 days, so you never study stale problems.

03

Covers every round

Functional reasoning, probability, estimation, market making games and the collaboration scored rounds.

04

120+ companies tracked

Also interviewing at Citadel, Two Sigma or Hudson River Trading? We have their questions too.

05

Difficulty and pattern data

Tagged by difficulty, round and category, so you know where prep time goes.

06

Candidate verified only

Reported by a candidate, then cross verified against multiple data points.

3.2×

Higher pass rate

120+

Companies tracked

3.2K+

Engineers using this

FAQ

Common questions

How are the questions sourced?

Directly from engineers who interviewed at Jane Street, then cross validated against other intel sources into a stack ranked list.

How often are questions updated?

We add new questions every 7 days and retire each one after 14 days, so the bank turns over twice in the window it covers. The firm hires a few hundred engineers a year, so the pool is small and each desk calibrates its own rounds.

Does Jane Street ask LeetCode questions?

Almost never. The rounds are probability, estimation and small functional programming problems, and the trading track adds mental arithmetic and market making games.

Can I use AI tools in the interview?

No. Every round is live with an interviewer watching, so there is nowhere to use one. The firm states it in the candidate instructions.

How is the offer decided?

By the people who interviewed you. There is no hiring committee and no calibration weeks later, which is why decisions land in days rather than weeks.

What does Jane Street pay a software engineer?

Around $525K in New York at two to five years, and about £331K in London. None of it is equity: a base in a narrow band plus a discretionary year end bonus that is most of the money.

How long does the process take?

Two to five weeks, and the decision itself lands in days. Scheduling the final day around a full office is what usually adds the delay.

Is this just for Jane Street?

No. GothamLoop covers 120+ companies including Citadel, Two Sigma, Hudson River Trading, Jump Trading and SIG.

The Jane Street interview cheat code nobody talks about

Five stages, and not one of them is a system design round

Recruiter call

First technical screen

Estimation and probability

The final day

Decision and offer

There are no levels here, and the bonus is the whole story

What Jane Street is asking right now

Why this actually works

Real questions, not guesses

Fresh every week

Covers every round

120+ companies tracked

Difficulty and pattern data

Candidate verified only

Common questions

Pricing plan

Company Interview Guides