Senior/Principal Security Infrastructure Engineer

  • IO Associates
  • Corsham, Wiltshire
  • Dec 19, 2025
Full time I.T. & Communications

Job Description

Senior/Principle Security Infrastructure Engineer
Permanent £70,000 to £90,000 Bristol (hybrid)

Our client is seeking a Senior/Principle Security Infrastructure Engineer to provide technical leadership and hands-on expertise in securing enterprise infrastructure and networks. This role focuses on resilience, compliance, and integrity across a complex multi-technology environment.


Key Responsibilities
  • Design, build and maintain secure on-premises and cloud network and system architectures

  • Harden Microsoft Server/Desktop platforms, Active Directory, and Group Policies

  • Deploy and manage MFA solutions (YubiKey, RSA) for enterprise identity and access protection

  • Secure virtualisation platforms (Hyper-V, VMware) and implement endpoint security (EDR, anti-malware, DLP)

  • Operate and optimise SIEM tools (Splunk, Microsoft Sentinel) for threat detection and incident response

  • Perform vulnerability assessments using Qualys and Tenable, driving remediation and continuous improvement

  • Align security controls with ISO 27001, NIST, CIS, and Cyber Essentials, supporting audits and compliance


Skills & Experience
  • Proven experience in infrastructure or network security within enterprise environments

  • Strong knowledge of Microsoft technologies (Windows Server/Desktop, Active Directory, Group Policy)

  • Hands-on experience with MFA, virtualisation, and network security appliances

  • Understanding of SIEM operations, vulnerability management, and endpoint protection

  • Familiarity with recognised security frameworks (ISO 27001, NIST, CIS, Cyber Essentials)

  • Excellent problem-solving and communication skills

  • DV cleared.

A key opportunity to lead technical security initiatives, embed best-practice controls, and work on strategic infrastructure projects with flexible working and career development opportunities.


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