Senior EDR/XDR Architect: Defender XDR & Falcon Expert

Marks and Spencer; Greater London; Hybrid; GBP 90,000 - 120,000; Full time

Benefits offered by this job

20% colleague discount

Holiday allowance

Discretionary bonus schemes

Pension and life assurance

Induction and training

Perks through Choices portal

Parental, adoption and neonatal leave

Wellbeing support

Volunteer day

Job summary

Marks & Spencer is seeking a Principal EDR & XDR Engineer to lead the engineering, optimisation and strategic development of our EDR/XDR platforms. You will act as SME for Microsoft Defender XDR and CrowdStrike Falcon, ensuring endpoint visibility, threat detection and incident response across large-scale environments.

Work closely with Security Operations, Incident Response and Threat Intelligence teams to develop advanced detections and improve platform performance while aligning with MITRE

Qualifications

• Extensive senior-level experience in EDR/XDR and cyber defence within complex enterprise environments.
• Proven capability in detection content development and platform optimisation across SIEM, EDR, and XDR.
• Strong leadership in security architecture, integrations and engineering best practices.

Responsibilities

• Lead engineering, governance and lifecycle management of Defender XDR and CrowdStrike Falcon for robust endpoint protection.
• Develop and tune high-fidelity detections across EDR/XDR and SIEM using MITRE ATT&CK and threat intel.
• Perform advanced threat hunting and support complex investigations with Security Operations and Incident Response teams.
• Provide technical leadership for security monitoring architecture, integrations and the cyber defence roadmap.
• Establish engineering standards, Detection-as-Code and CI/CD practices, and mentor engineers.

Skills

EDR

XDR

Security engineering

Security operations

Cyber defence

Threat hunting

Threat intelligence

MITRE ATT&CK

KQL

Incident response

Tools

Microsoft Defender XDR

CrowdStrike Falcon

Microsoft Sentinel

Job description

Marks & Spencer is seeking a Principal EDR & XDR Engineer to lead the engineering, optimisation and strategic development of our EDR/XDR platforms. You will act as SME for Microsoft Defender XDR and CrowdStrike Falcon, ensuring endpoint visibility, threat detection and incident response across large-scale environments.

Work closely with Security Operations, Incident Response and Threat Intelligence teams to develop advanced detections and improve platform performance while aligning with MITRE