Top Java Developer Jobs in London

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.

Design, develop, and maintain scalable backend systems for fintech products. Build REST APIs and microservices, improve existing systems (payments, treasury, transactions, crypto), and use Java, Spring Boot, and Postgres. Follow TDD, DDD, and CI/CD practices to deliver maintainable, high-performance services.

Design, develop, and maintain scalable, secure backend systems and microservices. Build REST APIs, improve existing systems (payments, treasury, transactions, crypto liquidity), and deliver high-quality code using Spring Boot, Java, Postgres, TDD, DDD, and CI/CD practices. Collaborate across teams in a hybrid office environment.

Design, develop, and maintain scalable backend systems and microservices (payments, treasury, transactions, crypto liquidity). Build REST APIs, improve existing systems, and apply clean code practices with TDD, DDD, and CI/CD.

As a Software Engineer, you'll design and build backend systems, develop APIs and microservices, and ensure system reliability while collaborating with cross-functional teams.

Lead DevOps practices to improve efficiency, software quality, and delivery. Implement and maintain CI/CD pipelines, IaC, container orchestration, monitoring, and database schema management. Collaborate with cross-functional teams, translate business requirements into technical solutions, and act as a DevOps SME while influencing stakeholders and promoting automation and best practices.

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.

Develop tooling for Citi's developer community using Java and SpringBoot. Engage in all SDLC phases and serve as a trusted consultant, enhancing developer experience and fostering continuous learning.

Work in an APS team to develop, support and automate cloud-native applications. Build and maintain CI/CD pipelines, infrastructure as code, container orchestration, monitoring, and collaborate with Java teams. Participate in on-call rotation, stakeholder engagement, and drive DevOps best practices across people, process, and tools.

Design, implement and evolve core components of a Java-based distributed runtime: cluster services, distributed data structures and execution engines. Work on partitioning, replication, coordination and recovery, write reliable low-latency production code, contribute to architecture, reviews and mentoring.

Design, build and maintain backend microservices using Java 17+, Spring Boot and related stack. Integrate third-party platforms, ensure performance and scalability, own technical decisions end-to-end, balance feature work with technical debt, and mentor junior engineers.

Develop and maintain Risk Intelligence KYC products (World-Check One/Verify). Implement and improve API Gateway services, migrate services to cloud (AWS), build secure, highly available and scalable microservices, collaborate with cross-functional teams, use agile practices, CI/CD and monitoring, and support production systems.

Design, build, and maintain scalable, highly available backend services in Java. Own backend architecture, optimize performance, develop APIs and integrations, support production, conduct code reviews, and contribute to AI engineering tools and infrastructure.

As a Full Stack Engineer, you will design and develop software solutions for trader efficiency, collaborate with stakeholders, ensure code quality, mentor junior developers, and manage full software lifecycle in a DevOps-focused environment.

The Senior Java Engineer will lead the technical architecture and development of the Equinox data platform, ensuring robust solutions, mentoring junior team members, and improving system efficiency and operational risk.

The Senior C++ / Java Developer designs, develops, and maintains software solutions, collaborating with teams to enhance platform stability and scalability, while mentoring junior engineers and ensuring high coding standards.

The Lead C++ / Java Developer is responsible for designing and maintaining low-latency FX market infrastructure, ensuring high availability and resiliency. This role emphasizes technical leadership and collaboration across teams to deliver robust solutions and improve system performance.

The Java Software Engineer will develop robust and scalable code for customer services using Java, AWS, and Postgres, while advocating for clean coding and best practices.

Administer, monitor, and support Java applications and Genesys Cloud. Provide production troubleshooting, minor bug fixes and enhancements, and act as primary POC for Java apps. Develop/support microservices using Java and Spring Boot, perform analysis of system behavior, and apply problem-solving and diagnostics to maintain service quality.

Lead design, development, and deployment of low-latency screening systems. Provide technical leadership, mentor engineers, drive architecture and CI/CD, collaborate with product and stakeholders, ensure scalability, performance, security, and deliver roadmap priorities.