Develop and maintain scalable Java backend services for data acquisition, processing, matching, analytics, and integrations. Build Java RMI applications, optimize performance, resolve production issues, improve resilience and monitoring, and uphold testing and engineering standards. The role also contributes to architecture and peer reviews, collaborates with QA, and mentors developers. It is a hybrid London position requiring office attendance one to two days weekly and occasional client travel.
We are looking for an experienced Senior Java Developer to join the engineering team at Xantura, helping to design, build, and evolve our cloud-based data and analytics platform used by local authorities and public sector organisations across the UK.
This is a hands-on senior engineering role focused on developing scalable backend systems, improving platform reliability and performance, and contributing to the ongoing evolution of our architecture, engineering standards, and development practices.
The role would suit someone who enjoys solving complex technical problems, working with large-scale data processing systems, and contributing to both technical delivery and engineering improvement initiatives.
Key Responsibilities
- Design, develop, maintain and support Java-based backend services for data acquisition, processing, matching, analytics and integration, built to scale and perform under load
- Build and maintain applications that use Java RMI for communication between services (hands-on RMI experience is essential)
- Show real depth of understanding in your solutions: explain and justify your design decisions, and judge when to use an existing library and when a custom implementation is the better choice
- Write clean, maintainable, well-tested code to agreed engineering standards, and collaborate with QA to meet the Definition of Done
- Investigate and resolve complex production issues and performance bottlenecks, and improve resilience, monitoring and operational reliability
- Contribute to architecture discussions, design and peer reviews, and mentor junior and mid-level developers
What are we looking for?
We’d love to hear from you if you have:
- A degree in Computer Science, Software Engineering or a related technical discipline, or equivalent practical experience
- Strong commercial experience developing enterprise applications in Java, with excellent knowledge of Java 17+, Maven, and JUnit and automated testing approaches
- Proven skill in performance optimisation and troubleshooting
- Experience with CI/CD pipelines, source control workflows and Azure DevOps or similar lifecycle tooling
- Strong grasp of software engineering principles, clean code and maintainable design, backed by sharp analytical and problem-solving skills
- Clear communicator who collaborates well in multi-disciplinary teams, with a proactive mindset, strong ownership and a commitment to continuous improvement
Location – This is a hybrid role based in our office in London (Borough). You would be expected to be able to work from the office at least 1-2 days per week. Some travel is also required for on-site client engagements as needed.
What can we offer you?
- Competitive salary reviewed annually
- Work for a passionate, mission-driven company solving society’s big problems
- Training and development opportunities
- 25 days annual leave (plus bank holidays)
- Company pension
- Private medical insurance
- Generous enhanced parental leave policies
- Cycle to work scheme
- Flu Vaccinations,
- Eye Test and contribution towards Glasses for VDU use
- Employee Assistance Programme
- Mental health and wellbeing support
- Remote GP access
- Counselling/therapy
- Physiotherapy
- Medical second opinions
About
At Xantura, we’re on a mission to reduce societal inequality by helping local authorities use data more effectively. Our AI-driven platform empowers frontline workers with the insights they need to prevent complex issues like homelessness or children being taken into care — before they happen. We make this possible by connecting siloed datasets, applying advanced machine learning to enrich the data, and using predictive analytics to identify those most at risk. Our platform then distills this into clear, actionable insights that help frontline staff intervene early and make a real difference. It’s an exciting time to join Xantura. We’re scaling quickly, bringing on new clients, strengthening our platform, and expanding into new areas. While we’re a technology company at heart, our true focus is on improving lives — and we’re looking for people who share that vision.
Xantura Limited London, England Office
London, United Kingdom
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