Software Engineering
Mock Interview

Interviews are an important part of Jane Street’s hiring process. We also recognize that they can be stressful, especially if you don’t know what to expect. We’d like to help alleviate some of that stress by sharing a recording of a mock interview.

In the video, two Jane Street software engineers—Grace and Nolen—take us through a typical Jane Street software engineering interview. (They use a now retired interview question that Grace hadn’t heard before.) At the end, they offer some high-level advice on approaching our interviews: how to communicate with your interviewer, how we think about code quality, and how to practice.

00:00 - Introductions from Grace and Nolen

01:20 - Interview begins

02:35 - Nolen describes the shape of the interview, and what to expect

04:58 - Nolen introduces the interview question

06:40 - Grace talks through her ideas

14:29 - Grace starts writing code

46:21 - Interview ends

46:45 - Nolen and Grace summarize what we look for in an interview

47:40 - Advice 1: Communication

48:44 - Advice 2: Clear and correct code

49:45 - Advice 3: Practice

The most important piece of advice is to practice. When you practice, make it as much like a real interview as you can: start a timer, talk through your ideas out loud, write out all parts of the problem (yes, even the parts that seem “easy”). That way, when the real thing comes, you’ll be more familiar with the environment.

To find practice problems you can try sites like Leetcode and Hackerrank. While the questions there aren’t exactly what you’ll answer in a Jane Street interview, they’re good sources of algorithmic practice.

(We’ve also written some blog posts about Jane Street interviews, including what an engineering interview is like and what we’re looking for in new hires.)