📍
London, UK

Tools & Compilers Research and Development Internship, Flexible

Internship
Finance
Software engineering
Posted:
December 29, 2025

Jane Street

Quantitative trading firm
87
Palpable Score
Apply >view company >

About the Position

We are excited to announce research internships in our Tools and Compilers group. We’re looking for PhD and masters students with outstanding research experience in programming languages, compilers, verification, and related areas.

Jane Street's Compilers team focuses on improving OCaml as a foundation for Jane Street's ever-growing technology stack, in collaboration with the greater OCaml community. We work on many different aspects of the compiler, aiming to make it easier for developers to express their ideas in OCaml, to improve the performance of the generated code, and to make the OCaml compiler itself faster and easier to use.

Over the years, we extended the type system with support for novel language features, re-engineered the optimizer ground-up, and added feedback-directed optimization. We also extend and enhance the surrounding toolchain, working on tools for profiling, debugging, documenting, and building automation. The vast majority of our work is open-source, and we upstream as much as we can to the mainstream OCaml compiler.

During the application process, we will work with you to identify a project that aligns with your research expertise and interests. Examples of areas we are interested in exploring include:

During the internship, you will work in collaboration with your mentors on one project for about 10-12 weeks. You’ll learn how we use OCaml in our day-to-day work, and gain exposure to the libraries and tools that are foundational to our internal systems. You’ll gain a better understanding of the wide range of problems we solve every day. You’ll try out new ideas and apply state-of-the art research to a large actively-developed production codebase.

You’ll also be able to access our physical and virtual educational resources, attend guest speakers and social events, and hopefully get a real sense of what it would be like to work here full time.

About You

We’re looking for PhD and masters students with outstanding research experience in programming languages, compilers, verification, and related areas. We don’t expect you to have a background in finance, OCaml, or functional programming. Fluency in English required. Please include the list of your peer-reviewed publications in your resume.

If you're a recruiting agency and want to partner with us, please reach out to agency-partnerships@janestreet.com.

About the company

Jane Street

Company overview
Jane Street is a quantitative trading firm and liquidity provider that makes markets across a broad range of asset classes. Jane Street builds much of the company’s technology in-house, with software engineering and research tightly linked to trading. Jane Street also runs a public engineering blog and open-source work that reflects a deep focus on programming languages, performance, and data systems. Jane Street serves institutional clients through trading and liquidity services alongside proprietary trading activity.

Locations and presence

Jane Street has major offices in New York, London, Hong Kong, Singapore, Amsterdam, and a presence in Chicago. Hiring is office-centered for most roles, with many processes culminating in in-person final rounds in a Jane Street office.

Palpable Score

87
/ 100
Jane Street offers unusually strong early-career access through recurring internships and multiple entry programs, backed by clear pay transparency and high compensation. The strongest signals are hands-on training, mentorship, and real project ownership for interns and new grads, plus benefits that reduce early-career financial stress. The main limiter is that Jane Street does not publish cohort outcomes like promotion rates or internship-to-full-time conversion rates, so outcomes scoring relies on indirect public signals.
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