Senior Java Developer

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

Job summary

London Stock Exchange is seeking a Senior Lead Scala Engineer to drive the engineering and delivery of a cloud-native market infrastructure service within the Equities platform. You will design, implement and maintain high-performance backend services in Scala, focusing on resilience, scalability, and observability.

You will collaborate with cross-functional teams, shape technical direction, and own the delivery of critical capabilities.

Qualifications

• Extensive Scala production experience, delivering enterprise-grade applications.
• Strong cloud and DevOps experience, AWS preferred.
• Practical knowledge of distributed systems, messaging and event-driven design.
• Experience with PaaS/SaaS and scalable backend services.
• Familiarity with Agile methodologies and cross-functional collaboration.

Responsibilities

• Design, implement, and maintain scalable backend services in Scala.
• Shape technical direction and engineering standards.
• Lead and support the growth and evolution of the platform.
• Contribute across solutioning, design, coding and testing life cycle.
• Promote open collaboration and accountability within the team.

Skills

Scala expertise

AWS cloud

DevOps

Microservices design

DDD & event-driven

Event-driven patterns

Shift-left testing

Agile (Scrum/Kanban)

ReactJS experience

Cross-functional collaboration

Tools

Play Framework

Akka

Cats/Scalaz

Docker

Kubernetes

Kafka

MSK

S3

Aurora

PostgreSQL

Flyway

Liquibase

GitLab

Job description

• The Senior lead Scala Engineer will play a key role in the engineering and delivery of a critical market‑infrastructure service within the Equities platform, with a strong focus on AWS cloud‑native development
• Reporting directly to the Senior Technical Delivery Engineer, Post Trade, the successful candidate will be responsible for designing, implementing, and maintaining performant, resilient, and scalable backend services built predominantly in Scala
• As a senior member of the engineering team, this individual will help shape technical direction, contribute to best-in-class engineering standards, and actively support the continued growth and evolution of the business
• This exciting opportunity requires a candidate to take Pride in their work and Ownership of their work. Have excellent engineering skills, communication skills, can-do behaviour and highly collaborative. Always positively encouraging the team
• A strong focus on engineering excellence and coding, adopting an open and hands‑on approach to problem‑solving and delivery. Engage deeply in technical design and implementation to ensure solutions are robust, scalable, and aligned with industry best practices
• Actively contribute to all stages of the product engineering life cycle—solutioning, design, coding, and testing—while promoting collaboration and transparency within the team to drive high‑quality outcomes
• Demonstrate ownership and pride in work, proactively taking on new responsibilities aligned with product engineering needs. Embrace and apply LSEG engineering principles, diving deep technically to build with purpose and foster excellence within the team through open collaboration
• Create an environment of engagement, challenge, and constructive questioning, ensuring trust and respect are maintained and a strong one‑team mentality is upheld

Expertise in building and maintaining DevOps pipelines, ideally with GitLabStrong understanding of microservices design, including pitfalls and best practicesWorking knowledge of event/message brokers such as Kafka and MQKnowledge of Domain-Driven Design (DDD) and event-driven architecture principlesSkilled in event-driven patterns for efficient and robust communicationProficient in shift-left testing using tools like JUnit, Cucumber, Gherkin, PACT, and Test ContainersExperience with containerization and orchestration using Docker and KubernetesStrong proficiency in both functional and object‑oriented programming paradigms, with the ability to apply the right approach to deliver robust, maintainable solutionsPlay Framework – for developing scalable, high-performance web applicationsAkka – for building concurrent, distributed, and resilient message‑driven systemsDeep practical expertise with Scala, including key frameworks and libraries such as:Cats / Scalaz – for implementing advanced functional programming abstractions and patternsProven experience delivering enterprise-grade Scala applications in production environments, with a focus on quality, resilience, performance, and observabilityStrong understanding of data structures, algorithms, concurrency, and multi-threading, with the ability to design efficient and scalable solutions for high-throughput systemsBasic understanding of cloud networking conceptsExperience working with major public cloud platforms, preferably AWSCloud ArchitectureHands-on use of cloud-based services such as AWS Aurora, MSK, S3, and IAMStrong SQL knowledge with experience in relational databases such as PostgresFamiliarity with database version control tools like Flyway and LiquibaseWorking knowledge of object storage solutions, e.g., AWS S3You have some experience of writing applications using JavaExperience working within Scrum and Kanban frameworksProven collaboration with cross-functional teams in scaled agile environmentsActive participation in sprint ceremonies, including Product Backlog RefinementStrong understanding and commitment to the ethos of agile workingYou have developed Web applications using ReactJS