I applied through a recruiter. The process took 1 week.
I got an interview invitation directly without an OA. They allow you to use any language you want in the interview, and it wasn't LeetCode-style, it was more of a simulation problem.
The following metrics were computed from 28 interview experiences for the Jane Street Software Engineer Intern role.
Jane Street's interview process for their Software Engineer Intern roles is extremely selective, failing the vast majority of engineers.
Candidates reported having very good feelings for Jane Street's Software Engineer Intern interview process.