Jane Street’s Interview Process & Questions

The info below is based on conversations with Jane Street engineers.

Jane Street's Interview Process for Software Engineers: 3 Steps

Mid to senior-level engineers interviewing at Jane Street can expect the following hiring process:

• Recruiter call (30 minutes)
• Technical phone screen (1 hour)
• Onsite (5 hours)

At Jane Street, the process is centralized, i.e., you interview with a central team and then get matched to a specific team after you pass the onsite loop.

General tips:

• Work on your coding stamina - the onsite is pretty intense.
• Practice coding something up from scratch – during the onsite, they’ll ask you to build something from nothing, e.g., a Tetris game
• Their interviewers want you to be collaborative, so ask lots of questions and communicate well throughout the process. They value collaboration as much as they do good code.
• Read Jane Street’s blog post about their interview process. Unlike most company pages, it’s detailed, useful, and good, and talks a lot about engineering interviews, specifically.
• Don’t try to impress them by coding in OCaml (their internal functional language of choice). Use the language you’re most comfortable in.

The entire process takes about 4 weeks.

Step 1: Recruiter Call

Jane Street’s recruiter call lasts 30 minutes, and it’s pretty standard fare – they’ll ask you about your previous experience, why you’re interested in Jane Street, your understanding of Jane Street’s value proposition, and what you’re looking for moving forward.

It’s really important, at this stage, to not reveal your salary expectations or where you are in the process with other companies. We’ve written a detailed post about salary negotiation that lays out exactly what to say if recruiters pressure you to name the first number.

Step 2: Technical Phone Screen

This is a pretty standard technical round, with one LeetCode medium-style question that will have two parts. Your interviewer will be more interested in how you think and how you arrive at the solution than an optimal solution. Communicate your assumptions and discuss alternate approaches as you work your way through the problem.

Step 3: Onsite

• 3 coding / system design hybrid rounds (75 mins each). These interviews will be conducted in CoderPad. For more detail about the kinds of questions to expect, see the Coding / System Design section below.
• Technical project deep dive (75 mins). For more info about what questions to expect, see the Technical project deep dive section below.

Types of Interview Questions to Expect at Jane Street

Coding / System Design

Whereas the technical screen before the onsite is LeetCode-style and more academic, the coding rounds during the onsite are a little bit more practical. They also blend coding and system design so you might have to whiteboard out some pieces initially before jumping into code.

You will get a problem statement that is underspecified. Your job is to ask the right questions before you dive in and while you are working. Get comfortable building things from scratch. You might be asked to:

• Design Tetris
• Design a video player API

You’ll have to design it, code it out, and go deep into the logic.

Below are the technical topics you’re likely to encounter in Jane Street interviews. To compile this list, we did two things. First, we spoke to some current and former Jane Street engineers. Then we cross-referenced all the anecdotes we heard with Glassdoor data AND our own data-set of mock interviews:

Technical Project Deep Dive

You will be asked to present an interesting, technically complex project that you’ve worked on, ideally something that you can talk about for an hour. They tell you not to over-prepare for this one, so you don’t necessarily need a robust presentation, but do prepare to answer a lot of questions about the project you’re presenting, the reasoning and logic behind it, and its impact.