Senior Systems Administrator

Role overview

We are looking for an experienced, hands-on Senior Systems Administrator to own our core infrastructure, business-critical systems, and technical operations. This role focuses on infrastructure stability, strategic improvements, mentoring, building internal capability, and ensuring operational resilience.

Key Responsibilities

• Manage and maintain IIS servers.
• Administer Microsoft 365 services, including Exchange Online, Teams, SharePoint,
• Active Directory, and Microsoft Intune for device management.
• Plan and execute infrastructure upgrades, disaster recovery testing, and business continuity initiatives.
• Oversee security tools and configurations, including Microsoft Defender, Fortigate firewalls, and Mimecast, and drive compliance improvements.
• Lead and mentor technical team members.
• Act as the technical bridge between internal stakeholders and vendors to resolve.
• Maintain the stability, security and documentation of critical IT infrastructure and Microsoft 365 environments.
• Support and regularly test disaster recovery and business continuity processes, identifying opportunities for improvement.
• Maintain clear IT procedures and documentation to reduce knowledge dependency and ensure continuity of support.
• Provide day-to-day operational support while escalating strategic and business-critical matters.
• Build internal IT capability to reduce unnecessary reliance on external vendors and service providers.
• Work collaboratively with the Senior IT Administrator, Help Desk and wider IT team, ensuring clear responsibilities, effective knowledge sharing and adequate operational backup.

Essential Knowledge and Skills

• 7+ years of Systems Administration experience managing enterprise infrastructure.
• 5+ years of hands-on Microsoft 365 administration, including Exchange Online, Teams, SharePoint, and active directory.
• Strong experience with Windows Server, Active Directory, IIS, and physical server management.
• Experience managing network infrastructure, including Fortigate firewalls and WAN connectivity.
• Demonstrated disaster recovery planning and testing experience.
• Ability to mentor technical staff and mediate between stakeholders and vendors.

Qualifications and Competencies required

• Degree in Computer Science, Information Technology, or related field, or equivalent professional experience in systems administration.
• Bonus: Microsoft 365 Administrator Certification (MS-102)