Senior Java Backend Engineer: Secure Microservices & Data

Addition Solutions LTD; Cheltenham; Hybrid; GBP 70,000 - 110,000; Full time

Job summary

Addition Solutions LTD is seeking a seasoned Java backend engineer to design secure, high-performance services for national security projects. You will build scalable microservices and REST APIs, integrate with analytics platforms, and ensure secure coding practices.

The role involves collaborating with stakeholders, contributing to architecture, and maintaining observability across production systems. The position emphasizes modern backend architectures, DevSecOps practices, and strong

Qualifications

• Expert Java (11+) with Spring Boot.
• Strong backend design and OOP skills.
• Experience building microservices and REST APIs.
• Experience with Docker, Kubernetes, CI/CD and automated tests.
• Active DV security clearance (essential).

Responsibilities

• Designing and developing secure Java-based backend services for mission-critical systems.
• Building scalable microservices and RESTful APIs to support intelligence and data platforms.
• Developing high-performance distributed applications capable of handling large, complex datasets.
• Integrating backend systems with streaming, analytics, and AI/ML-enabled platforms.
• Applying secure coding principles to meet strict performance, resilience, and security standards.
• Contributing to architectural decisions, code reviews, and continuous improvement initiatives.
• Implementing observability, logging, and monitoring to support production environments.
• Collaborating with stakeholders to translate requirements into robust technical solutions.

Skills

Java (11+)

Backend design

Distributed systems

OOP & design

Stakeholder collaboration

Security clearance

Tools

Docker

Kubernetes

CI/CD

Automated testing

Observability tools

Job description

Addition Solutions LTD is seeking a seasoned Java backend engineer to design secure, high-performance services for national security projects. You will build scalable microservices and REST APIs, integrate with analytics platforms, and ensure secure coding practices.

The role involves collaborating with stakeholders, contributing to architecture, and maintaining observability across production systems. The position emphasizes modern backend architectures, DevSecOps practices, and strong