Principal Systems Administrator

Join a business delivering critical, high-impact projects where secure and resilient infrastructure is essential. This Principal Systems Administrator role sits at the heart of enterprise technology, leading technical delivery, solving complex challenges, and helping shape future systems strategy.

Role Overview:

• Location: Hybrid working with UK travel as required
• Package: Competitive salary + performance bonus + private healthcare + flexible benefits
• Industry: Technology / Defence / Secure Infrastructure

What You’ll Be Doing:

• Providing technical leadership across core infrastructure environments and supporting wider engineering teams with expert guidance
• Designing, implementing and maintaining enterprise systems to ensure reliability, security and performance
• Diagnosing and resolving complex infrastructure, deployment and application issues across business-critical environments
• Leading systems administration activity across technical projects and programmes
• Supporting the delivery of a 24/7 operational service, including participation in an on-call rota and occasional out-of-hours change activity
• Working closely with third-party vendors to manage upgrades, support requests and technical escalations
• Contributing to service planning and helping shape technical standards, principles and best practice
• Ensuring processes align with recognised governance and security standards, including ISO frameworks

Main Skills Needed:

• Strong experience across enterprise systems administration and infrastructure support
• Hands-on expertise with virtualisation technologies, particularly VMware environments
• Experience with storage platforms, cloud services and Microsoft technologies including Windows Server, Exchange and Microsoft 365
• Knowledge of Citrix environments and secure remote access technologies
• Understanding of SQL Server administration and database fundamentals
• Experience working with Linux environments, automation tools and identity/access technologies
• Strong networking fundamentals including DNS, DHCP, TCP/IP and wider connectivity concepts
• Familiarity with IT service and delivery frameworks such as ITIL, Agile or Scrum
• Ability to work within highly secure environments and support business-critical systems

What’s in It for You:

• Flexible hybrid working options designed around work-life balance
• Optional compressed hours with every other Friday off
• Private healthcare and performance-related bonuses
• Career development opportunities with access to ongoing learning and progression
• The chance to work on meaningful, technically complex projects in a highly secure environment
• Exposure to a broad range of technologies with opportunities to influence infrastructure direction

Security Clearance:

Due to the nature of the work, applicants must be sole UK nationals and eligible to obtain and maintain UK Government SC clearance.

Call to Action:

Curious? Apply now — or grab five minutes with us to hear more.

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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