Machine Learning Research Engineer

Trading Interview; Greater London; Hybrid; GBP 120,000 - 170,000; Full time

Job summary

Jane Street is seeking a Research Engineer in London to advance machine learning platforms and research workflows. You’ll bridge research and engineering, building scalable training and inference infrastructure, and contributing to API design and system improvements.

The role emphasizes solid mathematical foundations, experimentation with neural networks and ensembles, and staying current with the ML literature.

Qualifications

• Strong background in machine learning research and model development.
• Ability to design and optimize training and inference pipelines.
• Excellent mathematical grounding in optimization, linear algebra, and statistics.

Responsibilities

• Develop and maintain training and inference infrastructure for ML models.
• Bridge research ideas to production, ensuring robust, reproducible results.
• Collaborate with software engineers to build scalable ML APIs and workflows.

Skills

ML research

Training/inference infra

Mathematics

PyTorch

JAX/TensorFlow

Tools

PyTorch

JAX

TensorFlow

Job description

We are looking for a Research Engineer with robust experience in machine learning and strong mathematical foundations to join our growing ML team and to help drive the direction of our ML platform.

Machine learning is a critical pillar of Jane Street's global business. Our ever-evolving trading environment serves as a unique, rapid-feedback platform for ML experimentation, allowing us to incorporate new ideas with relatively little friction. Our ML team is full of people with a shared love for the craft of software engineering, and for designing APIs and systems that are delightful to use.

We’ll rely on your in-depth knowledge of the ML ecosystem and understanding of varying approaches - whether it’s neural networks, random forests, gradient-boosted trees or sophisticated ensemble methods - to aid decision-making so we apply the right tool for the problem at hand. Your work will also focus on enhancing research workflows to tighten our feedback cycles. Successful ML Research Engineers will be able to understand the mechanics behind various modelling techniques, while also being able to break down the mathematics behind them. We’re looking for people who can be a true bridge between research and engineering, and can help us push forward the frontier of our model capabilities at all points of the stack. This could involve enabling a new scale in our technology stack, sitting on a team of Researchers to rapidly prototype a new research idea, or building workflow APIs that support a wide range of use cases.

If you’ve never thought about a career in finance, you’re in good company. Many of us were in the same position before working here. While there isn’t a fixed list of qualifications we’re looking for, if you have a curious mind and a passion for solving interesting problems, we have a feeling you’ll fit right in.

We're looking for someone with:

• Experience building and maintaining training and inference infrastructure, with an understanding of what it takes to move from concept to production
• A strong mathematical background; Good candidates will be excited about things like optimisation theory, regularisation techniques, linear algebra and the like
• A passion for keeping up with the state of the art, whether that means diving into academic papers, experimenting with the latest hardware or reading the source of a new machine learning package
• A proven ability to create and maintain an organised research codebase that produces robust, reproducible results while maintaining ease of use
• Expertise wrangling an ML framework – we're fans of PyTorch, but we'd also love to learn what you know about Jax, TensorFlow or others
• An inventive approach and the willingness to ask hard questions about whether we're taking the right approaches and using the right tools
• Fluency in English required

We were founded by a small group of traders and technologists in a tiny New York office. Today, we have more than 2,000 employees across five global offices. We trade…