Lead Java Developer

Business Unit: FTSE Russell – Index Platform Company: London Stock Exchange Group (LSEG)

About the Role

We are seeking a highly skilled and hands-on Lead Java Engineer with AI proficiency to help build the next generation FTSE Russell Index Platform. This platform underpins the calculation and distribution of FTSE Russell’s global family of indexes and requires advanced engineering, high precision data processing, and deep collaboration across global teams.

This is a deeply technical role focused on designing, building, integrating, and operationalising modern software and AI driven capabilities across internal platforms and client facing products. You will work with innovative technologies, contribute to complex algorithmic design, and drive engineering excellence in a high performance, data intensive environment.

Key Responsibilities

Core Engineering & Platform Delivery

  • Design, develop, and maintain complex Java and Python applications using modern engineering practices. Build / embed AI powered features into mission critical systems.
  • Architect and enhance services that support large scale, performance critical index computations.
  • Collaborate with Product Managers, UX, and engineering teams globally to deliver high quality products.
  • Lead projects end-to-end through requirements, design, development, testing, deployment, and operations.
  • Build and maintain automated test suites to ensure performance, scalability, and security.
  • Diagnose production issues, identify root causes, and deliver Level 3 support and fixes.
  • Conduct peer reviews, provide technical leadership, and mentor junior engineers.

What We’re Looking For

A proactive, creative engineering leader who enjoys solving complex problems, working hands-on with modern technologies, and driving AI enabled innovation. If you’re passionate about building resilient, intelligent, data intensive systems that power global financial markets, we’d love to hear from you.

We enhance each employee’s potential through personal development through a wide range of learning tools both formal and informal.

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. You will be part of a collaborative and creative culture where we encourage new ideas and are committed to sustainability across our global business. You will experience the critical role we have in helping to re-engineer the financial ecosystem to support and drive sustainable economic growth. Together, we are aiming to achieve this growth by accelerating the just transition to net zero, enabling growth of the green economy and creating inclusive economic opportunity.

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

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

Required Experience & Skills

  • 12+ years of hands-on backend software engineering experience.
  • Support the organisation’s AI adoption journey. Develop and enhance intelligent solutions using LLMs, LangChain/LangGraph, and agentic AI frameworks.
  • Establish engineering best practices for safe, scalable, traceable and production ready AI deployments across internal platforms and external product suites.
  • Strong algorithms, data structures, problem solving skills, and ability to translate business problems into scalable solutions.
  • Good command of coding standards and Strong understanding of both high level and low level software design
  • Expertise in:
  • Core Java, Python
  • Building highly distributed, data intensive systems
  • Microservices, REST APIs
  • RDBMS (Oracle/SQL Server/Postgres)
  • CI/CD tools (Jenkins/GitLab), DevOps automation
  • Docker, Kubernetes
  • JVM profiling & performance optimisation
  • Prior exposure to Level 3 production support.

Preferred / Nice-to-Have Skills

  • Experience leading or mentoring a team of engineers.
  • Experience within financial services or with financial market data.
  • Familiarity with in-memory caching, Spring Boot, Redis, Kafka.
  • Experience with BDD frameworks such as Cucumber, JBehave, or Karate.
  • Experience running Agile teams.