Top Java Developer Jobs in London

As a Principal Backend Engineer, you will build scalable backend services with Java, design APIs, implement microservices, and work with AWS cloud technologies.

Design, implement, and own scalable backend systems and APIs for global KYC/onboarding. Integrate risk systems, ensure compliance, drive technical roadmap, mentor engineers, and deliver large cross-team projects.

Work on Java-based microservices (Java 17/21, Spring Boot) to develop features, collaborate with architects and product owners, assist deployments and maintenance, support CI/CD (Jenkins/Terraform), run services on Kubernetes (EKS), and monitor production with Prometheus/Grafana. Contribute to code reviews and the teams system architecture.

The role involves designing and building cloud-native applications using Java and Spring Boot, focusing on scalable microservices for financial institutions while leading agile practices.

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.

As a Senior Software Engineer II, you will drive the technical vision for backend solutions, enhance recipient management, and ensure system reliability.

Build and maintain full-stack trading tools for systematic and credit portfolio trading. Collaborate with traders, quants, and product to define requirements, implement features (portfolio optimization, P&L analysis, recommendations), ensure production stability, and enable rapid, trader-friendly tooling using Java, Python, React, containerized deployments, and CI/CD.

The FX Risk Lead Java Developer designs and maintains Java microservices for high-throughput applications, optimizes data processing solutions, and ensures system reliability in a cloud-based environment.

As the FX Risk Lead Java Developer, you will design and develop Java microservices, optimize data solutions, implement real-time data processing, and ensure application scalability and reliability. You will collaborate with DevOps, conduct code reviews, and document system architecture.

As a Backend Engineer, you'll enhance accounting integrations, improve workflows, expand global offerings, and build a scalable platform architecture.

The role involves developing and maintaining trading and cash management systems using Java 21, focusing on microservices and cloud technologies, with collaboration across business functions.

Design and build investment features for Wise Assets, defining product and technical foundations. Develop web and distributed systems, collaborate cross-team, write clean, testable code, and advocate best practices to deliver customer‑focused incremental value.

Join the Bridge front office team to re-engineer and maintain an MT4/MT5/FIX bridge. Build robust backend systems in Java, design APIs, debug across the stack, support production on a rota, and contribute to front-end usability. Work collaboratively in a small, agile London-based team.

As a Full Stack Engineer, you will handle the full development lifecycle, engage with stakeholders, and promote best practices in engineering.

Design, build, and maintain high-performance Java backend systems that integrate and deploy AI/ML models. Develop RESTful microservices, optimize performance and security, implement CI/CD, work with cloud platforms and container orchestration, and collaborate with data scientists on scalable ML solutions.

Develop and maintain FIX APIs for IG Prime, enhance API capabilities, monitor performance, and support clients while collaborating with stakeholders.

Design, develop, and maintain cloud-based applications; provide technical leadership; manage junior team members; engage in agile project management.

Seeking a backend engineer to enhance user experiences and lead product decisions for an ad server platform. Responsibilities include developing features, collaborating with teams, ensuring code quality, driving improvements, and supporting production environments.

Lead an application development team to build and evolve next-generation trading applications, focusing on microservices and automation in finance.

Senior Java engineer to re-architect backend financial data mapping into scalable, testable ETL pipelines. Build and maintain Java-based microservices and Apache Beam pipelines, optimise cloud infrastructure via IaC and CI/CD, work with large datasets, ensure accuracy and observability, collaborate across product, QA and operations, and mentor peers.

The FX Risk Java Developer (VP) will develop high-performance Java applications for global banking, focusing on risk calculations and resilient systems. Responsibilities include designing data structures, implementing algorithms, and supporting projects in a front office environment.

Design, develop, and maintain high-performance, secure Java backend services and APIs. Ensure reliability, scalability, and cost-efficiency across microservices, databases, messaging systems, and capacity planning. Troubleshoot, profile, benchmark, and optimize systems (including ML applications) and collaborate with Kazakhstan stakeholders.

Build and scale Wise's Acquiring Platform to receive international payments. Design and implement backend services and RESTful APIs, integrate payment methods (Google Pay, Apple Pay, PIX, UPI), expand platform into ecommerce stores and PSPs, work on distributed systems, collaborate with stakeholders, and deliver shippable milestones.

Develop and maintain Java microservices for a 24/7 programmatic DOOH advertising platform. Design features, extend platform architecture, collaborate with product and engineering peers, write well-tested observable code, deploy to production using CI/CD, and support production infrastructure under a you-build-it-you-run model.

The role involves the technical implementation of FX trading systems, collaboration with teams, system architecture design, and enhancing deliverable quality. Candidates should have experience with FX, ultra low-latency development, and strong communication skills.