Lead Developer

London Stock Exchange; Greater London; On-site; GBP 120,000 - 160,000; Full time

Job summary

London Stock Exchange is seeking a highly skilled Lead Java Engineer with AI proficiency to design, build, and operate next-generation index platforms. You will architect scalable services, embed AI capabilities, and drive engineering excellence across global teams.

The role requires hands-on leadership, expertise in Core Java and Python, and a track record of delivering high-performance, data-intensive systems in complex environments.

Qualifications

• 10+ years of backend software engineering experience.
• Proven experience designing and delivering large-scale data-intensive systems.
• Hands-on leadership of engineering teams in Agile environments.
• Experience in financial services or financial market data is a plus.

Responsibilities

• Design, build, and maintain complex Java and Python applications.
• Integrate AI-powered capabilities into mission critical systems.
• Architect services to support large-scale index computations.
• Lead projects end-to-end from requirements to production operations.
• Build automated test suites for performance, scalability, and security.
• Diagnose production issues and provide Level 3 support and fixes.
• Mentor junior engineers and perform peer reviews.

Skills

Core Java

Python

CI/CD

DevOps automation

JVM profiling

Microservices

REST APIs

Algorithms

Data structures

LLMs

LangChain/LangGraph

Agentic AI frameworks

RDBMS

Docker

Kubernetes

Spring Boot

Redis

Kafka

BDD frameworks

Tools

Jenkins

GitLab

Docker

Kubernetes

Job description

• 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
• 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
• Expertise in:Core Java, PythonCI/CD tools (Jenkins/GitLab), DevOps automationEstablish engineering best practices for safe, scalable, traceable and production ready AI deployments across internal platforms and external product suitesJVM profiling & performance optimisationGood command of coding standards and Strong understanding of both high level and low level software designMicroservices, REST APIsStrong algorithms, data structures, problem solving skills, and ability to translate business problems into scalable solutionsSupport the organisation’s AI adoption journey. Develop and enhance intelligent solutions using LLMs, LangChain/LangGraph, and agentic AI frameworksRDBMS (Oracle/SQL Server/Postgres)Docker, KubernetesBuilding highly distributed, data intensive systems12+ years of hands-on backend software engineering experiencePrior exposure to Level 3 production supportA 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 youExperience within financial services or with financial market dataExperience with BDD frameworks such as Cucumber, JBehave, or KarateExperience leading or mentoring a team of engineersExperience running Agile teamsFamiliarity with in-memory caching, Spring Boot, Redis, Kafka