AD Engineer

La Fosse Associates; Greater London; On-site; GBP 94,000 - 127,000; Full time

Job summary

La Fosse Associates is seeking an experienced AD Engineer for a contract role in London, supporting on‑premises and cloud Microsoft infrastructure across a global enterprise environment.

The position focuses on Active Directory, Azure Entra ID, SSO and server migrations, with strong PowerShell scripting and a hands-on approach. Expect 2–3 days on-site, Inside IR35, and a dynamic cross‑functional team environment.

Qualifications

• 5+ years' experience with Microsoft infrastructure in an enterprise environment.
• Strong hands-on expertise across Active Directory, Group Policy, DNS and DHCP.
• Strong knowledge of Microsoft Azure and Entra ID.
• Extensive PowerShell scripting experience.
• Experience with PKI, certificate management and Domain Controller administration.
• Experience supporting SSO and authentication technologies.
• Experience with server migrations, upgrades, patching and application migrations.
• Understanding of high availability, disaster recovery and clustering.
• Experience supporting global infrastructure environments.
• Strong troubleshooting, analytical and problem-solving skills.
• Ability to communicate effectively with technical and non-technical stakeholders.

Responsibilities

• Manage and support Active Directory, including OU design, GPOs, Group Policy Preferences, Domain Controllers and roles management.
• Manage core infrastructure services including DNS, DHCP, WINS and PKI/certificate services.
• Support and manage Azure and Microsoft Entra ID services, including: Conditional Access, Role and Group Management, Entra Connect, Microsoft Authenticator, On-premise Active Directory integration, Group Policy and Intune policies, Defender for Identity.
• Support SSO and authentication services across the enterprise.
• Perform server migrations, upgrades, security patching and application migrations.
• Troubleshoot complex infrastructure issues and proactively identify potential service‑impacting problems.
• Work closely with Information Security to maintain infrastructure compliance.
• Develop and maintain technical documentation, procedures, RCAs and knowledge articles.
• Lead project and BAU activities, working with internal teams, suppliers and wider stakeholders.
• Provide technical leadership, mentoring and guidance to other team members.
• Contribute to infrastructure roadmaps, technology lifecycle management and service improvements.

Skills

Active Directory

Group Policy

DNS

DHCP

Azure Entra ID

PowerShell scripting

PKI / certificates

SSO / authentication

Server migrations

High availability / DR

Global infrastructure

Troubleshooting

Stakeholder communication

Job description

AD Engineer - Contract

£600 per day | Inside IR35
London | 2-3 days per week onsite

We're looking for an experienced AD Engineer to join a global enterprise IT environment, supporting and developing core infrastructure services across on-premise and cloud environments.

This is a hands‑on role focused on the management, support and lifecycle of Active Directory and Microsoft infrastructure, with strong exposure to Azure and Entra ID.

Key Responsibilities

• Manage and support Active Directory, including OU design, GPOs, Group Policy Preferences, Domain Controllers and roles management.

• Manage core infrastructure services including DNS, DHCP, WINS and PKI/certificate services.

• Support and manage Azure and Microsoft Entra ID services, including:

  • Conditional Access

  • Role and Group Management

  • Entra Connect

  • Microsoft Authenticator

  • On-premise Active Directory integration

  • Group Policy and Intune policies

  • Defender for Identity

• Support SSO and authentication services across the enterprise.

• Perform server migrations, upgrades, security patching and application migrations.

• Troubleshoot complex infrastructure issues and proactively identify potential service‑impacting problems.

• Work closely with Information Security to maintain infrastructure compliance.

• Develop and maintain technical documentation, procedures, RCAs and knowledge articles.

• Lead project and BAU activities, working with internal teams, suppliers and wider stakeholders.

• Provide technical leadership, mentoring and guidance to other team members.

• Contribute to infrastructure roadmaps, technology lifecycle management and service improvements.

Essential Experience

• 5+ years' experience working with Microsoft infrastructure in an enterprise environment.

• Strong hands‑on expertise across Active Directory, Group Policy, DNS and DHCP.

• Strong knowledge of Microsoft Azure and Entra ID.

• Extensive PowerShell scripting experience, including creation, testing and modification.

• Experience with PKI, certificate management and Domain Controller administration.

• Experience supporting SSO and authentication technologies.

• Experience with server migrations, upgrades, patching and application migrations.

• Understanding of high availability, disaster recovery and clustering.

• Experience supporting global infrastructure environments.

• Strong troubleshooting, analytical and problem‑solving skills.

• Ability to communicate effectively with technical and non-technical stakeholders.

Desirable

• F5 BIG-IP / load balancing experience.

• Experience migrating services to Azure.

• Microsoft certifications across Active Directory, Azure or related technologies.

• ITIL Foundation certification or demonstrable ITIL working practices.