Senior Security Engineer

Technical Cyber Security Engineer / Architect (Microsoft Sentinel & M365 Defender)

2 days per week on-site | London or Manchester

SC Clearance required - ESSENTIAL

A large national organisation is seeking a Technical Cyber Security Engineer / Architect (Microsoft Sentinel & M365 Defender) to join its Cyber and Infrastructure team, supporting the SOC (Security Operations Centre), permanently. This is a key role focused on strengthening cyber resilience across enterprise technology, helping to identify, defend against, and recover from evolving threats across cloud, network, and end-user environments.

You will work closely with security, infrastructure, and architecture teams to design and improve secure technology environments, support incident response, and help drive a security-by-design approach across the wider estate. This role will suit someone with strong experience across Microsoft Sentinel & M365 Defender
, alongside broader cyber architecture, engineering, and security operations capability.

• Secure architecture across enterprise networks, cloud, and end-user environments
• Hands‑on work with Microsoft Sentinel, M365 Defender
  , Defender for Cloud, Entra , and Conditional Access
• Supporting the SOC with incident response, vulnerability remediation and escalation
• Automating repeatable security tasks and improving operational efficiency
• Supporting compliance requirements, including PCI‑DSS
• Acting as a senior point of support within the team, including during the principal’s absence

• Strong experience in Azure security and cyber architecture
• Strong hands‑on knowledge of Microsoft Sentinel & M365 Defender (Entra  desirable)
• Experience across network security
  , cloud security and incident response
• Strong understanding of security operations, vulnerabilities and remediation