Java Engineer

KX Belfast, Northern Ireland, United Kingdom

KX software powers the time-aware data-driven decisions that enable fast-moving companies to outpace competitors, realizing the full potential of their AI investments. The KX platform delivers transformational value by addressing data challenges related to completeness, timeliness and efficiency, ensuring companies understand change over time and can achieve faster, more accurate insights at any scale, cost-effectively.

KX is essential to the operations of the world's top investment banks, aerospace and defence, high-tech manufacturing, healthcare and life sciences, automotive and fleet telematics organizations. The company has established offices and a robust customer base across North America, Europe, and Asia Pacific.

We are seeking a Senior/Intermediate Java Engineer to join our R&D team. The role focuses on backend and middleware development using Java 17 and Spring, working across a distributed, high‑availability system with kdb+ integration and strong security requirements.

• Develop, maintain, and optimise Spring‑based web applications and REST APIs using Java 17.
• Integrate backend services with real‑time kdb+ environments.
• Implement authentication (SAML/LDAP) and secure authorisation (RBAC/ABAC).
• Participate in distributed system design, including failover, replication, and node synchronisation.
• Apply secure coding practices to mitigate XSS, CSRF, SQL injection, and related vulnerabilities.
• Deploy and tune applications on Apache Tomcat.
• Develop unit, integration, and system‑level tests.
• Collaborate with Dev Sec Ops  on CI/CD pipelines and automated testing.
• Support production investigations with the Support team.

• Strong experience with Java 17 and Spring Framework (MVC, Security).
• Experience with Apache Tomcat deployment and tuning.
• Proficiency with Maven/Nexus and Git Lab CI/CD.
• Understanding of distributed systems, clustering, and failover.
• Strong knowledge of web security standards and OWASP Top 10.
• Optional:
  Exposure to front‑end tech, Python scripting, or AI/ML APIs.
• 8+ years of professional Java development.
• Enterprise‑level backend/middleware experience.
• Experience with Spring, distributed systems, and authentication/authorisation frameworks.
• Strong problem‑solving and analytical skills.
• Experience collaborating with Dev Sec Ops  and Support teams.

• Experience with real‑time or time‑series databases.
• Knowledge of kdb+ or similar high‑performance data engines.
• Experience with legacy modernisation projects.

This role can be based out of our London, Newry or Belfast Offices, and works under a Hybrid model.

• Data Driven:
  We lead with instinct and follow fact.
• Naturally Curious:
  We lean in, listen and learn fast.
• All In:
  We take ownership, take on challenges and give it our all.
• Individually tailored training and skills development
• Private healthcare package and Employee Assistance Programme
• Enhanced maternity and paternity package
• Wellness Days and Volunteer Days

• Associate

• Full‑time

• Information Technology
• Software Development