Software Engineer

Work on Technology That Protects What Matters

At SiXworks, we build secure digital solutions that support Defence and National Security missions. Our teams work on complex problems where reliability, security, and speed of innovation matter.

We’re looking for a QA Test Infrastructure Engineer who enjoys solving difficult technical challenges and wants their work to have real operational impact.

This role is on site 5 days a week in Somerset

What You’ll Do

As a QA Test Infrastructure Engineer, you’ll help design, build, and deliver secure digital solutions in highly secure environments. You’ll work alongside engineers, architects, and delivery specialists to develop technology that enables faster, safer decision-making for critical operations.

Your work may include:

• Ensuring quality of products as they move from prototype / proof of concept into Production.
• Analyse infrastructure requirements and architectures; identify test conditions; maintain traceability; log risks.
• Create infrastructure-focused test strategies and plans defining scope, environments, tooling, automation, and governance entry/exit criteria.
• Provision and validate test environments in collaboration with DevSecOps, ensuring OS, network, platform services, monitoring, and pipelines align to readiness standards.
• Design and execute tests across physical infrastructure and IaC, including functional, integration, regression, resilience, non-functional, and security-related scenarios.
• Apply Secure-by-Design principles; support security testing; contribute to accreditation, assurance, and compliance documentation.

What We’re Looking For

We value people who take ownership, think critically, and enjoy working as part of a collaborative team tackling complex challenges. You don’t need to tick every box, but we’re particularly interested in people with skills/experience in:

Infrastructure, Networking & Operating Systems

• Strong understanding of TCP/IP, DNS, DHCP, routing, switching, firewalls, VLANs, and related network behaviours.
• Experience with physical infrastructure setup and troubleshooting (routers, switches, cabling).
• Proficiency with Linux/Unix command line for diagnostics, configuration, and validation.
• Experience working across virtualisation platforms (VMware, VirtualBox) and cloud environments (AWS, Azure, GCP).

Infrastructure as Code (IaC)

• Terraform: writing/validating HCL, managing state, using modules.
• Ansible: building playbooks/roles, inventories, and validating idempotency.
• Kubernetes: deploying workloads, validating manifests, managing clusters, and testing containerised applications.

CI/CD & Automation

• Familiarity with CI/CD tooling (Jenkins, GitLab CI, GitHub Actions).
• Experience integrating IaC validation and environment checks into automated pipelines.
• Understanding of pipeline gating, automated readiness checks, and environment orchestration.

Security & Compliance

• Strong grounding in Secure-by-Design principles, IAM, least privilege, OS hardening, network segmentation, and observability.
• Experience within regulated or highly governed environments (e.g., MOD or similar).
• Ability to support compliance, assurance, and accreditation activity.

Just as important are curiosity, strong problem solving ability, and the motivation to continuously improve how technology is designed and delivered.

About SiXworks

SiXworks is a specialist digital innovation partner delivering secure, mission-critical technology to Defence and National Security organisations. We focus on digital experimentation, secure-by-design architecture, cloud technologies, and rapid application development to help our customers move faster and stay ahead of evolving challenges.

Our team combines expertise from across technology, business, and operational backgrounds including the armed forces creating a collaborative environment where practical thinking and innovation thrive.

Why Join Us

Our culture is guided by six principles: Agility, Security, Innovation, Quality, Collaboration and Inclusivity our North Star for how we work. SiXworks is a leading provider of secure digital solutions, specialising in digital experimentation and focused on fail-safe-fast cutting-edge technology solutions deployed in highly secure environments.

As an end-to-end digital innovation and delivery partner, we turn complex challenges into mission-critical digital advantages. This is a thrilling time for us, with ambitious plans for growth. We are looking for brilliant, experienced, driven and self-motivated people to join the team on our journey.

A word on UK Security Clearance

Due to the secure nature of the position and working environment, you must have or be eligible to obtain Security Clearance. More details relating to UK Security Clearance can be found on the GOV UK website

Interested?

Please apply!