Junior Quantitative Developer

LSEG (London Stock Exchange Group) is more than a diversified global financial markets infrastructure and data business. We are dedicated, open-access partners with a commitment to excellence in delivering the services our customers expect from us. With extensive experience, deep knowledge and worldwide presence across financial markets, we enable businesses and economies around the world to fund innovation, manage risk and create jobs. It's how we've contributed to supporting the financial stability and growth of communities and economies globally for more than 300 years.

The Optimisation Services Engineering Team focuses on designing, building, maintaining and supporting optimisation services that help financial institutions reduce risk, improve capital efficiency, and operate more resiliently. Our work has a direct impact on the stability and efficiency of global financial markets.

The Role

We are looking for a mid-level quantitative developer / financial engineer to join our optimisation services team. In this role, you will contribute to building and enhancing systems that power large-scale optimisation runs used by global financial institutions. You'll collaborate with colleagues in Software Engineering and Product Development to deliver reliable, high-quality solutions, while continuing to develop your expertise in quantitative methods and software engineering.

This is a product and client-focused role, where successful candidates will develop one or more of our services and will support live client optimisations. This is a collaborative role with opportunities to contribute both to strategic projects and continuous improvements, where your work will have visible and meaningful impact.

Examples of recent projects include:

• Implement improvements to our Interest Rates LCH Compression algorithm.
• Enhance our Counterparty Risk optimisation with new constraints and features
• Work on adding support for Hedge Funds and Clearing Brokers in Initial Margin optimisations
• Improve runtime performance of our core algorithms
• Streamlining workflows and improving system architecture to reduce manual steps

Key Responsibilities

• Contribute to the development and improvement of optimisation and analytics libraries
• Work with teammates to understand and improve how data flows through our systems
• Support optimisation runs alongside our Production team, helping ensure reliable execution
• Explore ways to tune models and solutions to better meet client needs
• Take part in both longer-term projects and shorter, iterative improvements
• Collaborate with colleagues across teams to share knowledge and improve our products

What We're Looking For

We are interested in people with a strong foundation in quantitative development and a curiosity for solving complex problems. You might bring:

• 3-5 years of experience using Python in a data-intensive or numerical environment
• Familiarity with software development practices such as testing, version control, and clean code design
• Experience working with libraries such as pandas and numpy
• Strong problem-solving skills and an interest in understanding how systems behave
• Ability to communicate technical ideas clearly to a range of audiences

Desirable

Experience in any of these areas would be a plus:

• Optimisation techniques (e.g., linear programming, mixed-integer programming, convex optimisation)
• Experience with optimisation libraries or modelling tools
• Understanding of financial products, derivatives, or risk concepts
• Exposure to UNIX/Linux or cloud environments such as AWS
• A background in mathematics, statistics, or related fields

Working With Us

• You'll work in a collaborative, supportive team where knowledge sharing is encouraged
• You'll have opportunities to learn and deepen your expertise in both quantitative methods and software engineering
• You'll be involved in solving real-world problems with tangible impact on financial markets
• We value continuous improvement—both in our systems and in how we work together

If you're excited about this role and feel that you could grow into it, we encourage you to apply. We welcome applicants from a wide range of backgrounds and experiences, and we are committed to building an inclusive environment where everyone can contribute and succeed.

Career Stage:
Senior Associate

London Stock Exchange Group (LSEG) Information:

Join us and be part of a team that values innovation, quality, and continuous improvement. If you're ready to take your career to the next level and make a significant impact, we'd love to hear from you.

LSEG is a leading global financial markets infrastructure and data provider. Our purpose is driving financial stability, empowering economies and enabling customers to create sustainable growth.

Our purpose is the foundation on which our culture is built. Our values of Integrity, Partnership, Excellence and Change underpin our purpose and set the standard for everything we do, every day. They go to the heart of who we are and guide our decision making and everyday actions.

Working with us means that you will be part of a dynamic organisation of 25,000 people across 65 countries. However, we will value your individuality and enable you to bring your true self to work so you can help enrich our diverse workforce.

We are proud to be an equal opportunities employer. This means that we do not discriminate on the basis of anyone's race, religion, colour, national origin, gender, sexual orientation, gender identity, gender expression, age, marital status, veteran status, pregnancy or disability, or any other basis protected under applicable law. Conforming with applicable law, we can reasonably accommodate applicants' and employees' religious practices and beliefs, as well as mental health or physical disability needs.

You will be part of a collaborative and creative culture where we encourage new ideas. We are committed to sustainability across our global business and we are proud to partner with our customers to help them meet their sustainability objectives. Our charity, the LSEG Foundation provides charitable grants to community groups that help people access economic opportunities and build a secure future with financial independence. Colleagues can get involved through fundraising and volunteering.

LSEG offers a range of tailored benefits and support, including healthcare, retirement planning, paid volunteering days and wellbeing initiatives.

Please take a moment to read this privacy notice carefully, as it describes what personal information London Stock Exchange Group (LSEG) (we) may hold about you, what it's used for, and how it's obtained, your rights and how to contact us as a data subject.

If you are submitting as a Recruitment Agency Partner, it is essential and your responsibility to ensure that candidates applying to LSEG are aware of this privacy notice.