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Opportunity

Tools & Compilers Research and Development Internship, Flexible

Research programming languages and compilers on Jane Street’s OCaml stack, including type systems, verification, systems-language features, testing, optimisation, and tooling.

London, United Kingdom
Internship
Software Engineering
The role

About the opportunity

This is a research internship in Jane Street’s Tools & Compilers group for master’s and PhD students working in programming languages, compilers, verification, or closely related areas. It is significantly more research-oriented than a standard software-engineering internship.

What the team works on

Jane Street’s compiler engineers improve OCaml as a foundation for the firm’s technology stack and work closely with the wider OCaml community. Their work spans the language, compiler, optimiser, and surrounding developer tooling. Past work includes extending the type system with new language features, rebuilding parts of the optimiser, adding feedback-directed optimisation, and improving profiling, debugging, documentation, and build automation.

A large portion of the team’s work is open source, and Jane Street upstreams changes to the mainstream OCaml compiler where possible.

What the internship looks like

You spend roughly 10–12 weeks on one research project chosen to connect your background with active work on the OCaml compiler or core libraries. Example areas include type systems that track locality and uniqueness, formal verification of OCaml programs, language features for systems programming, and compiler testing and validation. The goal is to apply research ideas to a large, actively developed production codebase.

What Jane Street looks for

This role is specifically for master’s and PhD students with strong research experience in programming languages, compilers, verification, or a related field. Finance, OCaml, and functional-programming experience are not required. Applicants are explicitly asked to include their peer-reviewed publications on their CV.