Senior M365 Platform Lead: Automation & Security in Hook

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Main Purpose of the Role

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.

Role Accountabilities

• 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, OneDrive, 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 PowerShell, 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.

Knowledge and Experience

Required Skills

• 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 (pipelines, policy‑as‑code, CI/CD, templates).
• Demonstrable experience implementing and enforcing Zero Trust principles across cloud collaboration platforms.
• Strong analytical thinking, architectural awareness and ability to balance UX, security and operational considerations.
• Excellent communication skills with the ability to influence stakeholders at all levels.
• Demonstrable experience leading others, through effective coaching and mentoring with a focus on psychological safety and behaviours that reinforce a healthy, high‑trust engineering culture.
• Relevant certifications: MD-102, MS-102, MS-700, MS-203, SC-300 or other Microsoft engineering certifications.
• Experience with ServiceNow or ITSM tooling.
• Familiarity with Agile practices and iterative delivery (Certified Scrum Master).
• Exposure to M&A activity, tenant‑to‑tenant migrations or large‑scale modernisation programmes.
• Experience with PowerBI dashboards for platform reporting.

Benefits

We’ve put everything in place to ensure you thrive. Competitive salaries, strong core values and an excellent benefits package that includes:

• Onsite parking.
• Company Pension Scheme.
• Cycle to work scheme.
• An Employee Assistance Programme.
• Enhanced maternity, paternity, and adoption leave.
• Access to trained Mental Health First Aiders.
• Access to BCA Rewards which provides online and store discounts with a range of retailers.
• And so much more...

We are proud to be Level 1 Disability Confident and committed to ensuring our recruitment process is inclusive and accessible. Our policy is to employ the best qualified people and provide equal opportunity for the advancement of employees including promotion and training and not to discriminate against any person because of gender, race, ethnicity, age, sexual orientation, religion, belief, or disability.