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About LSEG

LSEG (London Stock Exchange Group) is a diversified global financial markets infrastructure and data business. It offers a comprehensive suite of trusted financial market infrastructure services and an open‑access model to provide flexibility, stability and trust for customers pursuing their ambitions.

About the Team

Reporting to the Director of Architecture within the Risk Intelligence team, this group develops critical services that support anti‑money laundering efforts in the financial markets.

Role Summary

We’re looking for a Principal Java Architect to lead the design, evolution, and governance of our Java‑based platforms. The role is hands‑on, high‑impact, shaping backend architecture, coaching senior engineers, and ensuring world‑class engineering practices and tooling.

Responsibilities

• Architectural Leadership: define and evolve the architecture of our Java platforms, ensuring alignment with business goals and long‑term maintainability.
• Code Quality & Reviews: perform technical reviews, enforce clean code principles (e.g., SOLID), and ensure adherence to architectural standards.
• Mentorship & Coaching: guide senior engineers and technical leads, fostering a culture of excellence, autonomy, and continuous learning.
• Event‑Driven & Domain‑Driven Design: champion modern architectural paradigms such as event‑driven systems, DDD and microservices.
• Tooling & Developer Experience: own and enhance the Java development ecosystem—including build tools (Maven/Gradle), CI/CD pipelines, static analysis, and testing frameworks.
• Framework & Codebase Contribution: contribute to and evolve shared libraries, frameworks, and platform components that power our services.
• Innovation & Research: stay ahead of the curve on Java ecosystem developments (e.g., Project Loom, GraalVM, Kotlin, Quarkus) and lead strategic adoption.
• Cross‑Functional Collaboration: work closely with product, architecture and platform teams to deliver cohesive, performant and secure solutions.

Qualifications

• Deep Java expertise: Spring/Spring Boot and the broader JVM ecosystem.
• Architectural mastery: strong grasp of software architecture patterns (hexagonal, layered, microservices), DDD, event‑driven systems (Kafka, Pulsar, etc.).
• Engineering excellence: mastery of SOLID principles, design patterns, dependency injection and ORMs (Hibernate, JPA).
• Tooling fluency: experience with Gradle/Maven, CI/CD (Jenkins, GitLab), static analysis tools (SonarQube), test automation.
• Optimisation mindset: knowledge of algorithms, runtime complexity, data structures and query optimisation for SQL and NoSQL with scalable indexes.
• Cloud‑native thinking: experience writing software for cloud platforms (AWS, GCP, Azure), containerisation (Docker, Kubernetes) and observability.
• Security & resilience: understanding of secure coding, fault tolerance and system resilience in distributed environments.
• Leadership & influence: ability to lead by example, influence without direct authority, and communicate complex ideas clearly.

Preferred Skills / Experience

• Reactive programming experience (Project Reactor, RxJava).
• Exposure to GraphQL, gRPC or API gateway patterns.
• Experience building agents or using agentic frameworks such as LangChain4j or equivalent.
• Contributions to open‑source projects or technical blogs.

Benefits & Culture

LSEG offers a range of tailored benefits and support, including healthcare, retirement planning, paid volunteering days and wellbeing initiatives. Working with us means being part of a dynamic organisation of 25,000 people across 65 countries and a culture that values diversity, sustainability and innovation.

Location

Greater London, England, United Kingdom

Equal Opportunity Statement

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’ religious practices and beliefs, as well as mental health or physical disability needs.

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