Systems Administrator (Security Cleared)

Systems Administrator (Security Cleared).

Join a specialist technology team delivering mission-critical solutions in highly secure environments. This is a hands-on role where infrastructure, security, and software engineering come together to solve complex, high-stakes challenges.

Role Overview:

• Location: Fareham/Hybrid (2 days per week on site, Thursday & Friday)
• Day Rate: £450 to £533 per day Inside IR35
• Start Date: ASAP
• Contract Length: 4 Months initially, with scope for extension.
• Industry: Secure Technology/Defence/Advanced Engineering

What You’ll Be Doing:

• Designing, building and maintaining secure, air-gapped Linux environments (Rocky 9).
• Automating infrastructure using Ansible, creating and managing playbooks and offline repositories.
• Implementing and enforcing robust firewall policies and system hardening standards.
• Reviewing, validating and improving scripts generated by tools or engineers to ensure security and suitability.
• Supporting and maintaining C++ development environments within a secure ecosystem.
• Managing patching processes for air-gapped systems.
• Overseeing event logging, monitoring and overall system resilience.
• Ensuring compliance with strict security standards and best practice frameworks.

Main Skills Needed:

• Candidates must hold an active Security Clearance; this is essential.
• Full UK Driver's License & Access to a vehicle.
• Strong Linux administration experience, including system hardening and secure configuration.
• Proven expertise with Ansible, YAML and infrastructure automation in restricted environments.
• Solid scripting capability (Bash, Python) with the ability to review and validate generated code.
• Experience working with C++ environments.
• Deep understanding of firewall configuration, logging and monitoring within secure systems.
• Experience operating in air-gapped or highly controlled environments.

Desirable:

• Experience within MOD or wider government environments.
• Knowledge of JSP 440/604/453, Secure by Design and CIS Benchmarks.
• Experience in patching and maintaining isolated systems.

What’s in It for You:

• Work on high-impact, security-critical projects that genuinely matter.
• Be part of a specialist team trusted with complex technical challenges.
• Exposure to cutting-edge engineering in secure environments.
• A platform to deepen your expertise across infrastructure, automation and secure development.
• A culture that values accountability, innovation and high standards.

Careers move fast. Let’s make sure yours is heading the right way.

We are an equal opportunity employer and value diversity at our company. We do not discriminate on the basis of race, religion, colour, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status.

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