Infrastructure Engineer

Keystone Group; Cookstown; Hybrid; GBP 45,000 - 60,000; Full time

Benefits offered by this job

Pension

Life Assurance

Healthcare Cashback Plan

Cycle to Work Scheme

Employee Discount Scheme

Professional Development

Job summary

The Keystone Group is seeking an experienced Infrastructure Engineer to manage and secure our on-premise and cloud infrastructure across a hybrid environment. You will oversee Active Directory, Entra ID administration, and the migration path from VMware to Hyper-V/Azure while delivering reliable, scalable IT services.

You will patch, monitor, and harden systems, implement BAU processes, contribute to security controls and incident response, and document configurations for the wider IT team.

Qualifications

• Candidates should have a degree in IT or computing and 5+ years in IT infrastructure roles.
• Strong experience administering Windows Server environments and Active Directory at scale.
• Hands-on experience with Microsoft Entra ID (Azure AD) and hybrid identity environments.

Responsibilities

• Administer and maintain on-premise and cloud infrastructure in a hybrid environment.
• Lead migration efforts from VMware to Hyper-V/Azure and manage identity and access controls.
• Provide day-to-day operational support, incident response, and documentation of infrastructure configurations.

Skills

Windows Server Administration

Active Directory (multi-domain)

Microsoft Entra ID / Azure AD

VMware / Hyper-V

Networking fundamentals

Security & patch management

Education

Degree in IT / Computer Science

Tools

VMware vSphere

Hyper-V

Microsoft 365 Admin

Job description

About The Role

We're looking for an Infrastructure Engineer to help us manage, secure, and modernise our on-premise and cloud infrastructure. You'll work across a hybrid estate - supporting existing on-premise systems while playing an active role in our ongoing migration to modern cloud and hybrid platforms, and in the day-to-day administration of Microsoft Entra ID. This is a hands-on engineering role with genuine scope to shape how infrastructure is built and secured across the group.

What You'll Be Doing

On-Premise Infrastructure

• Administer and maintain our server estate (physical and virtualised), including patching, capacity management, and lifecycle planning
• Support and help decommission legacy/EOL systems (servers, SQL Server instances, and applications) as part of the group's estate rationalisation programme
• Manage Active Directory across multiple domains, supporting ongoing consolidation and identity modernisation work
• Administer core infrastructure services: DNS, DHCP, file/print, backup and disaster recovery, VOIP Telephony
• Support the group's migration from VMware vSphere7 to vSphere8/9 or to Hyper-V/Azure, including build, testing, and cutover activity

Entra ID & Cloud Identity Administration

• Own day-to-day administration of Microsoft Entra ID: user and group lifecycle, licensing, app registrations, and enterprise applications
• Support Entra ID tenant consolidation across all group brands, including domain and UPN/primary SMTP alignment
• Configure and maintain Conditional Access policies, MFA enforcement, and password policy in line with NCSC guidance
• Administer Privileged Identity Management (PIM) and just-in-time (JIT) access for privileged roles
• Support hybrid identity sync (AD to Entra ID) and troubleshoot synchronisation issues

Cloud & Security

• Support Microsoft 365 administration alongside Entra ID (Exchange Online, SharePoint, Teams)
• Assist with Azure infrastructure (App Services, Functions, storage, networking) supporting group applications and data platforms
• Contribute to the group's Cyber Essentials Plus programme, including remediation of findings and ongoing control maintenance
• Operate and tune endpoint and network security tooling (e.g. Microsoft Defender, Sophos, ThreatLocker, Ivanti Patch Management, SIEM alerting)
• Support security patching, vulnerability remediation, and hardening across both on-premise and cloud infrastructure
• Participate in incident response and root-cause investigation for infrastructure and security incidents

General

• Produce and maintain clear documentation for infrastructure, configurations, and standard operating procedures
• Work within change management (CAB) processes for planned infrastructure changes
• Provide 2nd/3rd-line escalation support and mentor junior team members where required
• Collaborate with the wider IT team on projects spanning infrastructure, security, and identity

You will also demonstrate:

• Strong problem-solving skills, with a structured and analytical approach to diagnosing and resolving issues.
• A proactive mindset, with the confidence to identify improvements, challenge existing ways of working and drive solutions through to completion.
• A strong security mindset and understanding of the importance of maintaining secure, resilient and well-managed infrastructure.
• Excellent communication skills, with the ability to explain technical issues and solutions clearly to both technical and non-technical stakeholders.
• The ability to work effectively in a changing environment, managing multiple priorities while maintaining a high standard of delivery.
• A collaborative approach, with a willingness to share knowledge, support colleagues and contribute to the wider IT team and Group objectives.

What We're Looking For

• Educated to Degree Level with a Minimum 5 years of experience working in a similar capacity as an Infrastructure Engineer or have a minimum of 10 years’ experience working in an IT Infrastructure role
• Proven experience administering Windows Server environments and Active Directory at scale
• Hands‑on experience administering Microsoft Entra ID (Azure AD) - users, groups, Conditional Access, and app registrations
• Hands‑on experience with virtualization platforms (VMware and/or Hyper-V)
• Practical understanding of core networking (DNS, DHCP, VLANs, firewalls)
• Some exposure to Azure or another public cloud platform (IaaS/PaaS fundamentals)
• Working knowledge of endpoint security, patch management, and vulnerability remediation
• Strong troubleshooting skills and a methodical approach to problem‑solving
• Clear communicator, comfortable working with both technical peers and non-technical stakeholders

What We Offer

• Opportunities for professional development and career progression
• A supportive, values-driven and inclusive working environment
• Competitive salary and benefits package
• 32 days annual leave, increasing with service
• Pension
• Life Assurance
• Healthcare Cashback Plan
• Enhanced Family Friendly policies
• Additional employee benefits including access to our Cycle to Work Scheme, Employee Discount Scheme, Employee Recognition awards, Employee Assistance Programme.

A Bit About Us

For more than three decades, the Keystone Group has grown to become one of the UK and Ireland's largest family-owned construction product manufacturers. Driven by a relentless focus on innovation and customer excellence, the Group employs over 2,000 employees across 28 sites, supplying cutting-edge building solutions to growing markets in the UK & Ireland, Europe, Australia and North America. Its portfolio includes market-leading brands in the steel, light & environmental and timber sectors.