Principal AI Engineer

ABOUT US

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 dedication 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. Through a comprehensive suite of trusted financial market infrastructure services – and our open‑access model – we provide the flexibility, stability and trust that enable our customers to pursue their ambitions with confidence and clarity.

People are at the heart of what we do and drive the success of our business. Our culture of connecting, creating opportunity and delivering excellence shape how we think, how we do things and how we help our people fulfil their potential. We embrace diversity and actively seek to attract individuals with unique backgrounds and perspectives. We break down barriers and encourage teamwork, enabling innovation and rapid development of solutions that make a difference.

Our workplace generates an enriching and rewarding experience for our people and customers alike. Our vision is to build an inclusive culture in which everyone feels encouraged to fulfil their potential. We know that real personal growth cannot be achieved by simply climbing a career ladder – which is why we encourage and enable a wealth of avenues and interesting opportunities for everyone to broaden and deepen their skills and expertise.

As a global organisation spanning 70 countries and one rooted in a culture of growth, opportunity, diversity and innovation, LSEG is a place where everyone can grow, develop and fulfil your potential with meaningful careers.

The Principal Engineer is a senior technical expert responsible for designing, developing, and delivering high‑quality software solutions. This role emphasizes deep technical proficiency, innovation, and hands‑on development, including advanced work in AI technologies such as prompt engineering and large language models (LLMs). The ideal candidate will serve as a technical authority, proving concepts with the latest AI technology or practices in the form of a spike or proof of concept.

This person will be responsible for pushing the boundaries of what is possible, turning vision or concept into a technical solution, driving best practices and ensuring scalability, performance, and security across systems.

• Software Development
  • Design and implement complex, scalable, and secure applications.
  • Write clean, efficient, and maintainable code in Java, Python, and other high‑level languages.
• Technical Expertise
  • Provide architectural guidance and ensure adherence to best practices.
  • Optimize system performance and troubleshoot critical issues.
• AI Development
  • Develop and refine prompt engineering strategies for LLM‑based applications.
  • Integrate and optimize Large Language Models (LLMs) into products and workflows.
  • Collaborate with AI teams to improve model performance and user experience.
• Innovation & Research
  • Stay current with emerging technologies, frameworks, and AI advancements.
  • Prototype and evaluate new tools and methodologies for adoption.
  • Work closely with product managers, QA, and other developers to deliver high‑quality solutions.
  • Participate in code reviews and contribute to technical documentation.
• Process & Quality
  • Advocate for automation, testing, and continuous integration practices.
  • Ensure compliance with security and regulatory standards.

• 12+ years in software development, with at least a year in AI Development.
• Extensive experience in software development and system architecture.
• Proven ability to deliver complex projects with high technical standards.
• Strong technical background in Java, Python, and/or other high‑level programming languages.
• Expertise in designing scalable and secure systems.
• Hands‑on experience with AI…