Top Java Developer Jobs in London

Senior individual-contributor responsible for hands-on implementation, performance, scalability, resilience, and operational excellence of a Java/AWS-based Risk Screening platform. Partners with architects and SREs, leads complex changes, optimises large databases, and mentors engineering teams to ensure reliable, high-performance production systems.

Lead Java Developer responsible for delivering Real-Time and On-Demand Risk enhancements, managing the full development lifecycle, collaborating with global teams, and driving operational improvements.

Senior Software Engineer responsible for designing scalable Java and Spring backend systems, developing secure REST APIs, and contributing to Vue/TypeScript applications. The role includes architectural leadership, technical decision-making, automated testing, CI/CD, cloud development, mentoring engineers, client collaboration, and delivery across multiple initiatives. The engineer will also evaluate emerging technologies, promote automation, and help adopt responsible AI practices to improve engineering effectiveness.

Build, maintain, and scale a multi-venue collateral management platform and related reference data and accounting systems. Design resilient, real-time event-driven distributed systems, integrate trading venue data, contribute to architecture, and own production delivery and support.

Develop complex distributed systems using Java, Kafka, and Kubernetes. Mentor team members and contribute to all phases of the product lifecycle.

Design, build, test, and maintain Java 17+ microservices for a banking modernization program. Develop REST APIs and messaging integrations, containerize and deploy services through CI/CD, integrate relational and NoSQL databases, and address performance, resilience, security, and observability. Participate in Agile delivery, solution design, code reviews, testing, and production releases while collaborating with architects, analysts, testers, and product owners.

The Java Developer will design, code, and implement features for insurance policy and claims handling systems, ensuring compliance with regulatory changes. Responsibilities include testing, debugging, and collaborating with stakeholders while using a test-driven approach to software development.

The Principal Java Engineer will design and optimize low-latency payment systems, develop APIs, deploy applications on AWS, and mentor peers.

As a Senior Software Engineer, you'll solve financial problems through coding, develop distributed systems, and work collaboratively in a fast-paced environment.

Software Engineers at Zopa focus on building scalable microservices and solving financial problems, working collaboratively with various teams.

Build, test, and operate cloud-native back-end services using Java (and Python), following secure coding and accessibility (WCAG) standards. Design and deploy RESTful microservices on Azure, work with SQL Server, CI/CD (GitHub Actions), write unit/integration tests, mentor junior developers, participate in agile practices and code reviews, and support service monitoring and incident fixes.

The Staff Software Engineer will design and manage end-to-end data pipelines, ensuring data quality and governance while collaborating across Java and Python systems, including event schema design and AI tooling.

Design and maintain scalable Java backend systems, REST APIs, microservices, and distributed architectures. Lead technical and architectural decisions, promote testing and automation, mentor engineers, collaborate with clients and cross-functional teams, and evaluate emerging technologies including AI to improve engineering delivery.

The role involves diagnosing and resolving production incidents, developing fixes in Java, collaborating with teams, and improving system reliability while managing documentation and monitoring performance.

Design, build, and optimize low-latency, high-throughput Java microservices and REST APIs for payments. Deploy and scale services on OpenShift/Kubernetes and AWS, integrate with MongoDB/other datastores, improve performance and observability, mentor engineers, and drive architectural best practices.

Design, develop and maintain Java server-side applications and libraries for high-performance, distributed trading systems. Contribute to protocol and library design, write clean test-driven code, benchmark and profile components, troubleshoot production issues, participate in code reviews, and pair with teammates to deliver reliable, high-performance messaging infrastructure.

Contract Java Developer to build a brand-new digital bank. Work on core Java development within banking/finance projects in a fast-paced, innovative environment. Rolling contract with growth opportunities.

Backend-focused Java full‑stack developer to build banking and payments systems. Work with large-volume data and large online platforms, using cloud, microservices, Kubernetes, and optionally Kotlin and Golang. London-based, long-term contract.

Develop backend Java-based tools for an IoT-focused technologist, including desktop tools, IDE plugins or smartphone apps. Work on APIs, tooling, and potentially JavaFX-based UIs, using Eclipse or IntelliJ for development.

Join a fast-paced team building a new digital bank platform from scratch. Develop backend services using JVM languages, design distributed systems, work on database development, and contribute high‑quality engineering across the platform.