Senior M365 Platform Lead: Automation & Security

Job Title: Senior M365 Platform Engineer

Salary: Competitive + Benefits!

Location: Hybrid working, home & UK travel, as & when required

Working Hours: Monday - Friday 40 hours per week

Job Status: Permanent

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The Senior M365 Platform Engineer is a senior member of the Collaboration Platform team within Technology Operations. This role provides strategic leadership, technical expertise, governance and operational oversight across CAG’s Microsoft 365 ecosystem. As the Senior M365 Platform Engineer, you will help shape and drive the vision for a modern, secure and automated digital workplace across our multi-tenant M365 environments. You will lead a high‑performing engineering capability, ensuring our platforms deliver exceptional user experiences, robust security and continuous innovation.

Working closely with partners in Information Security, Architecture, Platform Engineering and business stakeholders, you will ensure our M365 services are scalable, secure, intuitive and fully optimised to support the way our people work, whilst ensuring we focus on providing a customer‑centric service. This is a role for someone who combines deep technical authority with strategic thinking, team leadership and a passion for automation, reliability and digital transformation.

• Act as the technical authority for the Microsoft 365 platform across all tenants
• Support to define the strategic roadmap for M365 collaboration services aligned to organisational priorities and security standards
• Lead and mentor the M365 platform team, promoting a culture of automation, continuous improvement and proactive platform ownership
• Drive modernisation initiatives, ensuring legacy migrations, platform enhancements and user experience improvements are delivered to high standards
• Support the governance model for the M365 ecosystem, including Intune, Exchange Online, One Drive, Teams & SharePoint Online
• Lead the development and enforcement of tenant standards, configuration baselines, naming conventions, taxonomy frameworks and policy‑as‑code practices
• Ensure consistent service performance and security in a multi‑tenant organisation, enabling seamless cross‑tenant collaboration and identity usability
• Champion automation‑first approaches using Power Shell, Microsoft Graph and CI/CD tooling to reduce manual effort and eliminate configuration drift
• Establish and maintain platform monitoring, reporting and health dashboards for proactive service management
• Drive operational maturity, including incident response processes, root cause analysis, service reviews and performance optimisation
• Partner with business teams, change managers and training functions to increase adoption and maximise value from the M365 suite
• Act as a senior escalation point for collaboration‑related incidents and business‑critical service issues
• Communicate complex technical concepts clearly to non‑technical audiences, ensuring alignment with organisational outcomes
• Oversee creation and maintenance of high‑quality documentation: technical designs, configuration catalogues, runbooks, troubleshooting guides and knowledgebase articles
• Ensure all platform changes follow robust change control and are traceable, reviewable and auditable
• Oversee the design, implementation and optimisation of Intune‑based endpoint management across Windows, iOS, Android and macOS
• Direct the development of device taxonomies, dynamic targeting models, compliance frameworks and update strategies at enterprise scale
• Provide escalation expertise for complex endpoint issues, Autopilot failures, compliance drift or Conditional Access impacts

• 5+ years of hands‑on experience across M365 platforms, with deep expertise in Intune and endpoint management at enterprise scale (5000+ devices)
• Proven experience leading technical teams or acting as a senior escalation/authority within an engineering function
• Strong experience operating in multi‑tenant M365 environments with complex identity, collaboration and compliance requirements
• Expertise in Powershell, Microsoft Graph and automation frameworks…