Senior Infrastructure Engineer

Reply; Greater London; On-site; GBP 75,000 - 110,000; Full time

Job summary

Reply specialises in designing and implementing solutions based on new communication channels and digital media. The Senior ICT Infrastructure Engineer role in the UK focuses on engineering, architecture and governance of core endpoint, identity and Microsoft 365 platforms, including building and administering a new tenant.

You will work across 1st-3rd line support, drive security baselines, Zero Trust and ISO 27001 compliance, and mentor colleagues within a small ICT team.

Qualifications

• Experienced senior infrastructure engineer with hands-on expertise across Microsoft 365, Intune and Entra ID
• Strong focus on security, compliance, and Zero Trust in government/defence contexts
• Proficient in infrastructure-as-code approaches and scripting
• Able to mentor junior ICT colleagues and lead technical discussions
• Knowledge of ISO 27001, GDPR, Cyber Essentials frameworks

Responsibilities

• Own engineering, architecture, and governance of core UK ICT platforms including Microsoft 365 and endpoint security tooling
• Provide hands-on 1st-3rd line support and complex incident resolution
• Lead provisioning, configuration, and administration of a new Microsoft 365 tenant
• Design and maintain automation and IaC solutions (PowerShell, Graph API, Terraform)
• Ensure alignment with security and compliance frameworks and governance artefacts
• Mentor junior team members and define escalation paths
• Produce operational reporting and service trend analysis
• Engage with internal stakeholders and vendors to shape infrastructure roadmaps

Skills

Microsoft 365

Intune

Entra ID

Conditional Access

Purview

PowerShell

Microsoft Graph API

Terraform

Zero Trust

Security governance

Tools

PowerShell

Microsoft Graph API

Terraform

Job description

Reply specialises in designing and implementing solutions based on new communication channels and digital media. Structured as a network of highly specialised companies, Reply supports leading European industrial groups in sectors such as Telco & Media, Industry and Services, Banking and Insurance, and Public Administration, helping define and develop business models enabled by new paradigms such as AI, Cloud Computing, Digital Media, and the Internet of Things. Reply's services include Consulting, System Integration, and Digital Services.

Role Overview:

The Senior ICT Infrastructure Engineer is a hands-on, technically authoritative role at the heart of Reply's UK internal infrastructure, responsible for the engineering, architecture, and governance of core endpoint, identity, and Microsoft 365 platforms, including the end-to-end build and administration of a new tenant. Operating across 1st, 2nd, and 3rd line support, the post-holder combines day-to-day user support and desk-side work with expert-level incident resolution, security-focused configuration, and platform optimisation in a government and defence context. They will own and enhance key services such as Intune, Entra ID, Purview, Conditional Access and endpoint security, while leading improvement initiatives, driving compliance with frameworks such as ISO 27001 and Cyber Essentials, and acting as a senior technical reference point and mentor within the ICT team.

Responsibilities:

• Own the engineering, architecture, and governance of core UK ICT platforms, including Microsoft 365, Intune, Entra ID, Purview, Conditional Access, and endpoint security tooling.
• Provide highly hands-on 1st, 2nd, and 3rd line support, from routine user requests and laptop builds through to expert-level troubleshooting and complex incident resolution.
• Lead the end-to-end provisioning, configuration, and ongoing administration of a new Microsoft 365 tenant, ensuring robust security baselines, Zero Trust principles, and appropriate controls for government and defence contexts.
• Design, implement, and maintain automation and infrastructure-as-code solutions (e.g. PowerShell, Microsoft Graph API, Terraform) to improve consistency, efficiency, and compliance.
• Ensure alignment with key security and compliance frameworks (including ISO 27001, GDPR, Cyber Essentials and relevant government standards), maintaining governance artefacts and technical standards documentation.
• Act as a senior technical reference point within the ICT team, providing mentoring, guidance, and review for junior colleagues and helping to define escalation paths and support best practices.
• Produce operational reporting and service trend analysis, recommending and delivering infrastructure improvements to enhance reliability, performance, and security.
• Engage with internal stakeholders and third-party vendors (including Microsoft) to resolve escalations, shape infrastructure roadmaps, and ensure services effectively support Reply's consultants and project teams.

About the Candidate:

• Experienced senior infrastructure engineer with at least five years in endpoint management or infrastructure roles, ideally within secure or regulated environments.
• Deep, hands-on expertise across Microsoft 365, Intune (including Autopilot), Entra ID, Conditional Access, and Purview, with a strong focus on security, compliance, and Zero Trust.
• Proficient in PowerShell scripting and familiar with the Microsoft Graph API; ideally comfortable with infrastructure-as-code approaches such as Terraform.
• Strong grounding in Windows and macOS security administration, patching, BitLocker, Defender for Endpoint, DLP, and broader endpoint security tooling.
• Demonstrable experience working with and owning security and compliance frameworks (e.g. ISO 27001, GDPR, Cyber Essentials) and an understanding of government security classifications.
• Confident communicator who can lead technical discussions, engage credibly with stakeholders at all levels, and mentor junior ICT colleagues.
• Holds (or can rapidly obtain) SC clearance, with continuous UK residency for at least five years and willingness to travel to Reply's UK offices as required.
• Highly hands-on, pragmatic, and comfortable switching between low-level 1st line tasks and complex 3rd line engineering work as part of a small, collaborative team.

Reply is an Equal Opportunities Employer and committed to embracing diversity in the workplace. We provide equal employment opportunities to all employees and applicants for employment and prohibits discrimination and harassment of any type regardless of age, sexual orientation, gender, identity, pregnancy, religion, nationality, ethnic origin, disability, medical history, skin colour, marital status or parental status or any other characteristic protected by the Law.

Reply is committed to making sure that our selection methods are fair to everyone. To help you during the recruitment process, please let us know of any Reasonable Adjustments you may need.