Lead​/Principle Software Engineer

Lead/Principle Software Engineer

Clearance Required:

Active SC Clearance (Mandatory) The Opportunity We're looking for an experienced Software Engineer to join a high-performing team delivering secure, mission-critical solutions for Defence, National Security, and Government customers.

This role offers the opportunity to design and develop modern backend platforms and services that support some of the UK's most complex and secure technology programmes. Working within Agile, cloud-native environments, you'll leverage cutting-edge commercial and open-source technologies to build scalable, resilient, and high-performing systems across both public and private cloud infrastructure. You'll play a key role in the full software development lifecycle, from solution design through to deployment and operational support, while collaborating with multidisciplinary teams to deliver innovative solutions that make a real-world impact.

Please note:

Active SC Clearance is an essential requirement for this position. Due to the nature of the work, candidates must already hold current and active SC Clearance. Unfortunately, sponsorship or clearance applications cannot be supported for this role.

Key Responsibilities Design, develop, deploy, and enhance backend platforms, applications, and services that support mission-critical programmes. Deliver secure, scalable, and maintainable software solutions that meet both functional and non-functional business requirements. Participate in Agile ceremonies, including sprint planning, story refinement, estimation, and retrospectives. Deliver incremental software releases and continuous improvements through modern Agile delivery practices. Collaborate closely with engineers, architects, and product stakeholders across cross-functional teams.

Take ownership of the services and applications your team delivers, ensuring ongoing reliability, performance, and supportability. Build, maintain, and optimise Continuous Integration and Continuous Deployment (CI/CD) pipelines. Contribute to engineering standards, best practices, and quality assurance processes across the development lifecycle. Support knowledge sharing and foster a collaborative engineering culture. Assist in troubleshooting, root cause analysis, and resolution of production issues when required.

Skills & Experience Essential 5 years' commercial software engineering experience delivering production-grade solutions within complex environments. Strong commercial experience developing applications using Java . Experience working with other JVM-based technologies such as Kotlin and/or Scala .

Experience with messaging and event-streaming technologies such as Kafka . Strong experience integrating with backend services including PostgreSQL , Redis , and S3/Object Storage solutions. Deep understanding of microservices architecture , distributed systems, and modern software design patterns. Experience working with Big Data technologies and data-intensive applications. Experience operating within Agile Dev Sec Ops  environments. Knowledge and application of Zero Trust Architecture principles.

Strong experience with CI/CD pipelines , automated deployments, and modern software delivery practices. Commitment to clean coding standards, code reviews, defensive programming, and high-quality technical documentation. Experience using source control and collaboration platforms including Git Hub , Git Lab , and the Atlassian Suite . Strong problem-solving skills with the ability to design and implement scalable technical solutions.

Desirable Experience working within AWS, Azure, or other cloud-native environments. Knowledge of containerisation and orchestration technologies such as Docker and Kubernetes. Experience supporting highly regulated industries such as Defence, National Security, Government, or Critical Infrastructure. Exposure to high-volume, real-time, or event-driven architectures. Relevant industry certifications across software engineering, cloud, or security disciplines. What You'll Bring Strong backend engineering expertise with a passion for developing secure, scalable, and reliable systems.

The ability to lead technical discussions and influence engineering decisions across teams. A thorough understanding of modern software engineering principles and best practices. A proactive approach to ownership, taking responsibility for services from initial design through to production support. A collaborative mindset with the ability to work effectively…