Lead ML Engineer

Lead ML Engineer

Full-Time 70000 - 90000 £ / year (est.) No working from home possible
London Stock Exchange Group

At a Glance

  • Tasks: Design and build AI tools that transform enterprise systems into smart workflows.
  • Company: Join a leading global financial markets infrastructure provider with a focus on innovation.
  • Benefits: Enjoy tailored benefits, healthcare, retirement planning, and paid volunteering days.
  • Other info: Be part of a diverse team committed to sustainability and community support.
  • Why this job: Make a real impact in AI while working in a dynamic and creative environment.
  • Qualifications: Strong Python skills and experience with AI frameworks are essential.

The predicted salary is between 70000 - 90000 £ per year.

The Corporate Engineering AI team is the central enablement and platform delivery function for LSEG’s internal agentic AI ecosystem. The team’s mission is to scale safe, high‐quality AI capabilities across the enterprise by providing shared platforms, patterns, governance, and delivery support.

CE AI owns and operates core AI platforms including LSEG AI Assist, the Question Answering Service (QAS), and the Internal MCP Gateway. Rather than delivering individual business use cases end‐to‐end, the team enables product engineering groups across LSEG to expose knowledge, data, and actions to AI agents in a consistent, governed, and repeatable way.

The team operates a Central MCP Delivery model: building critical MCP tools and services “for” product teams where required, while simultaneously defining standards, patterns, and platform capabilities that allow teams to progressively move towards self‐service contribution.

This programme delivers an LSEG‐owned, production‐grade agentic AI platform with MCP as its extensibility layer. The scope of work includes:

  • Building and operating LSEG AI Assist, an in‐house agentic experience capable of reasoning, planning, and tool‐calling.
  • Operating QAS, the enterprise RAG and search layer used to ground agent responses in approved data sources.
  • Delivering a production Internal MCP Gateway providing discovery, security, policy enforcement, observability, and lifecycle management for MCP tools and Skills.
  • Designing and building MCP servers and Skills that expose internal and vendor systems safely to agents.
  • Establishing evaluation, quality control, and governance mechanisms so MCP tools and Skills can be promoted through PTB/PTO and operated with confidence at scale.

The programme follows a “build for” model today, with a strong emphasis on defining the future product and platform experience, patterns, and contribution pathways that will enable federated scale over time.

Responsibilities

  • Design and build MCP servers and tools that expose enterprise systems and workflows to AI agents.
  • Implement Skills that orchestrate tools, data, and reasoning into repeatable, governed workflows.
  • Contribute to the LSEG AI Assist agentic harness, including planning, tool‐calling, and orchestration logic.
  • Build secure API wrappers where backend systems lack suitable authentication or entitlement models.
  • Work closely with product teams in a “build for” capacity, transferring knowledge and establishing reusable patterns.
  • Shape the developer experience for MCP and Skills, including templates, contribution guidance, and standards.
  • Collaborate with Quality Engineers and SREs to ensure solutions meet quality, governance, and operational readiness expectations.

Skills

  • Strong Python development experience.
  • Hands‐on experience with LLM and agent frameworks and agentic reasoning patterns.
  • Practical understanding of Model Context Protocol (MCP), including server and tool patterns.
  • FastAPI and REST API design and implementation experience.
  • Experience with prompt engineering and RAG‐based architectures.
  • Containerisation and Kubernetes‐based deployment experience.
  • Ability to work across platform, product, and governance boundaries in an enterprise environment.

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.

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.

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

Lead ML Engineer employer: London Stock Exchange Group

At London Stock Exchange Group, we pride ourselves on being an exceptional employer that champions innovation and sustainability. Our collaborative work culture fosters professional growth, offering employees ample opportunities to develop their skills in a dynamic environment focused on sustainable investment. Located in the heart of London, we provide a vibrant workplace with access to industry-leading resources and a commitment to making a positive impact in the financial sector.

London Stock Exchange Group

Contact Details:

London Stock Exchange Group Recruitment Team

We think you need these skills to ace Lead ML Engineer

Python Development
LLM and Agent Frameworks
Agentic Reasoning Patterns
Model Context Protocol (MCP)
FastAPI
REST API Design
Prompt Engineering