Senior ML Engineer

London Stock Exchange Group; Greater London; On-site; GBP 90,000 - 130,000; Full time

Job summary

London Stock Exchange Group (LSEG) is seeking a Manager-level ML Engineer for the Corporate Engineering AI program in London. You will design and build MCP servers, implement agentic Skills, and collaborate with product teams to deliver secure, scalable AI capabilities across the enterprise.

You will contribute to LSEG AI Assist and the Internal MCP Gateway, focusing on governance, reliability, and repeatable patterns. Strong Python, FastAPI, and Kubernetes experience are essential.

Qualifications

• Proficient in Python development for scalable AI platforms.
• Hands-on experience with LLMs, agents, and agentic reasoning patterns.
• Solid understanding of MCP architecture, servers, and tool patterns.
• Experience designing and implementing APIs with FastAPI and REST.
• Knowledge of prompt engineering and RAG-based architectures.
• Experience containerising and deploying on Kubernetes.
• Ability to collaborate across platform, product, and governance teams in a large enterprise.

Responsibilities

• Design and build MCP servers and tools exposing enterprise systems to AI agents.
• Develop Skills to orchestrate tools, data and reasoning into repeatable workflows.
• Contribute to the LSEG AI Assist harness, including planning and orchestration logic.
• Create secure API wrappers where authentication/entitlement is missing.
• Collaborate with product teams in a build-for capacity to transfer knowledge.
• Shape developer experience for MCP and Skills with templates and guidelines.
• Coordinate with Quality Engineers and SREs to meet governance and reliability standards.

Skills

Python development

LLM & agent frameworks

MCP understanding

FastAPI & REST

Prompt engineering

Kubernetes deployment

Enterprise cross-functional work

Tools

Kubernetes

Job description

Corporate Engineering AI (CE AI) Team

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.

LSEG AI Assist / Internal MCP Programme of Work

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.

ML Engineers – Responsibilities & Skills

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.

Career Stage: Manager

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.

LSEG (London Stock Exchange Group) 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 culture of connecting, creating opportunity and delivering excellence shapes how we think, how we do things and how we help our people fulfil their potential. Our Data & Analytics, Capital Markets and Post Trade divisions have a combined power that provides a comprehensive, integrated suite of trusted financial market infrastructure services to help our customers pursue their ambitions. Explore our divisions LSEG is headquartered in the United Kingdom, with significant operations in 70 countries across Europe, the Middle East, Africa, North America, Latin America and Asia Pacific. Find out more Get to know some of our people who are pushing the boundaries of technology, finance and more around the world.