Software engineer

You write the software that runs a trading firm, from the tools its trading desks use to the systems its accounting team relies on. Software engineers work in all parts of Jane Street, so the seat is defined by the problem you are handed rather than by a product line. Some engineers build tools for traders, some build systems for the accounting team, and some build the shared foundations everyone else depends on, such as network monitoring or risk models.

This is a graduate seat. You join as a full-time permanent employee at the point of finishing university, and you are not expected to know the firm's tools before you arrive. Most of the engineers already there joined with little or no experience of the firm's main language and learned it on the job.