Senior Java Engineer

London Stock Exchange Group; Greater London; On-site; GBP 120,000 - 170,000; Full time

Benefits offered by this job

Healthcare benefits

Retirement planning

Wellbeing initiatives

Job summary

London Stock Exchange Group (LSEG) seeks a Senior Java Engineer with hands-on expertise in Java and Python to help build and operate the next generation FTSE Russell Index Platform. You will design, implement, and optimize AI-enabled features and large-scale index computations in a high-performance data environment.

The role requires deep software engineering experience, strong problem-solving abilities, and collaboration with global teams to deliver reliable, scalable products across internal

Qualifications

• 10+ years of backend software engineering experience.
• Experience building large-scale, data-intensive systems.
• Strong Java and Python development skills.
• Experience with AI-enabled features and production deployments.

Responsibilities

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

Skills

Java

Python

AI proficiency

Distributed systems

REST APIs

CI/CD

Unix/Linux

Problem solving

Software design

Tools

Docker

Kubernetes

Jenkins

GitLab

Oracle

PostgreSQL

Job description

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

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. LSEG is headquartered in the United Kingdom, with significant operations in 70 countries across EMEA, North America, Latin America and Asia Pacific. We employ 25,000 people globally, more than half located in Asia Pacific. LSEG’s ticker symbol is LSEG.

Our People

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.

About the Role

We are seeking a highly skilled and hands‑on Senior 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

• 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 largescale, 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.

Required Experience & Skills

• 10+ 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.
• Background as a Scrum Master or experience running Agile teams.

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.

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.

Values and Purpose

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.

Equal Opportunities

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.

Sustainability and Charity

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.

Benefits

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

Additional Company Information

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. Working with us means that you will be part of a dynamic organisation of 25,000 people across 70 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. Find out more Get to know some of our people who are pushing the boundaries of technology, finance and more around the world.