Full Stack Engineer - React/Java

This Full Stack Engineer role sits within a data and analytics team focused on delivering highly reliable, scalable trading and trade management solutions. You will work as a hands-on Java developer, maintaining and enhancing backend and web-based applications while contributing to the ongoing evolution of a modular, end-to-end trading platform and its web user interfaces. The platform enables users to execute a wide range of trading strategies across multiple markets and time zones, manage risk throughout the trade lifecycle, and connect with a broad network of execution, prime and clearing brokers.

• Design, develop and implement backend services and web applications that support a complex trading and trade management platform.
• Write clean, maintainable and well-tested code in line with established engineering standards and best practices.
• Participate in technical design discussions and collaborate closely with senior engineers and architects to shape system architecture and solutions.
• Work closely with frontend developers to integrate backend services with user interface components, ensuring seamless end-to-end functionality.
• Support troubleshooting, debugging and performance optimisation activities across backend and web applications.
• Break down user stories into well-defined technical tasks and deliver them within agreed timelines in an Agile environment.
• Maintain and enhance existing systems, ensuring stability, reliability and continuous improvement of core services and user interfaces.
• Collaborate effectively within cross-functional Agile teams, including product owners, QA engineers and other developers.
• Build and maintain positive working relationships within the team and contribute to a collaborative, supportive engineering culture.
• Communicate technical concepts clearly and confidently to both technical and non-technical stakeholders.
• Continuously develop technical expertise by learning and adopting modern technologies, frameworks and tools relevant to full stack development.

• Strong proficiency in Java (Java 21 preferred), including solid understanding of core concepts such as collections, concurrency and memory management.
• Solid commercial experience with Spring Framework (Spring 4+) and Spring Boot 3.x for building backend services.
• Proven experience designing, building and consuming REST APIs.
• Good knowledge of modern frontend technologies and frameworks (including version 17) and their integration with backend services.
• Strong understanding of web application architecture, client–server communication and related design patterns.
• Hands-on experience with SQL and relational databases, ideally PostgreSQL.
• Proficiency with version control systems, particularly Git, and build tools such as Maven or Gradle.
• Strong focus on writing clean, readable code with comprehensive unit tests and active participation in code reviews.
• Familiarity with Agile development practices and working within cross-functional Agile teams.
• Comfortable working in Linux/Unix environments for development, deployment and troubleshooting.
• Approximately 4–8+ years of professional software engineering experience in backend or full stack roles.

• experience working with JSF and JSP-based applications or other legacy user interface technologies.
• Familiarity with modern frontend practices, including component-based architectures and contemporary JavaScript frameworks.
• experience with CI/CD pipelines and automated testing practices to support continuous integration and delivery.
• Exposure to Docker or other containerisation technologies.
• Basic understanding of distributed systems concepts and patterns.
• Familiarity with broader Spring ecosystem tooling and libraries.
• Knowledge of financial systems, trading platforms or capital markets workflows is an advantage.

You will join a collaborative engineering culture that values technical excellence, knowledge sharing and continuous improvement. The environment encourages open communication, active participation in design discussions and ongoing professional development with modern technologies and frameworks. You will work in cross-functional Agile teams, gaining exposure to complex, high-impact systems in the financial technology domain while contributing to platforms that support global markets and diverse participants.

You will work in a modern, technology-focused environment building and maintaining backend services and web applications that support a large-scale trading and trade management platform. The technology stack includes Java (with a preference for Java 21), Spring Framework and Spring Boot, RESTful services, SQL and PostgreSQL, modern frontend frameworks, Git, Maven or Gradle, and CI/CD tooling, with exposure to Docker and containerisation. Development typically takes place on Linux/Unix systems, following Agile methodologies with close collaboration between developers, QA and product teams. The role involves regular code reviews, automated testing and performance optimisation within a professional, team-oriented setting.

London, UK

500.00 - 750.00 GBP Daily

Trading as TEKsystems. Allegis Group Limited, Maxis 2, Western Road, Bracknell, RG12 1RT, United Kingdom. No. (phone number removed). Allegis Group Limited operates as an Employment Business and Employment Agency as set out in the Conduct of Employment Agencies and Employment Businesses Regulations 2003. TEKsystems is a company within the Allegis Group network of companies (collectively referred to as "Allegis Group"). Aerotek, Aston Carter, EASi, Talentis Solutions, TEKsystems, Stamford Consultants and The Stamford Group are Allegis Group brands. If you apply, your personal data will be processed as described in the Allegis Group Online Privacy Notice available at (url removed)>

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