About this role
About the Role We are seeking a Senior Level 3 Wintel Site Reliability Engineer (SRE) to join our infrastructure engineering function in London. This is a hands-on "builder" position focused on modernizing, automating, and maintaining our enterprise Windows Server ecosystem and hybrid cloud integrations.
Moving away from routine ticket handling, this role demands a code-first engineering mindset. You will treat infrastructure as code, design resilient architecture, and author production-grade CI/CD automation pipelines to eliminate operational toil across enterprise Windows, Active Directory, and hybrid Azure platforms.
Key Responsibilities CI/CD Pipeline Authoring: Design, build, and maintain production-grade infrastructure deployment pipelines using Azure DevOps (YAML/Git) to deliver automated, auditable, and reliable infrastructure changes.Code-First Infrastructure Automation: Leverage PowerShell (including PowerShell DSC / module development) and Infrastructure as Code (Terraform) to automate OS deployment, configuration management, and lifecycle processes across hybrid server estates.Level 3 Infrastructure Operations: Serve as the senior technical escalation point for complex Windows Server OS internals, Active Directory forests, Group Policies, Kerberos authentication, and core domain services.Site Reliability Engineering (SRE): Implement proactive observability, monitoring, automated recovery workflows, and performance optimization to enforce continuous service availability and operational resilience.Architecture & Modernization: Partner with engineering, cloud, and security teams to eliminate configuration drift, reduce technical debt, and drive enterprise-scale infrastructure standards. Essential Technical Requirements Wintel OS & Active Directory Depth: Proven Level 3 experience managing complex enterprise Windows Server environments, Active Directory, GPO, DNS, and Kerberos at scale.Advanced PowerShell Automation: Advanced hands-on capabilities writing original, modular PowerShell scripts and configuration-as-code (PowerShell DSC) for automated deployment and configuration enforcement (beyond simple maintenance scripting).CI/CD & Pipeline Creation: Active, hands-on experience authoring multi-stage Azure DevOps (YAML) deployment pipelines from scratch-not simply executing pre-built pipelines.Infrastructure as Code (IaC): Solid working experience with Terraform for declarative infrastructure provisioning.Engineering Mindset: A strong "builder" mentality focused on reducing manual toil, establishing automated guardrails, and building reliable, scalable systems. Desirable Experience Prior experience working within regulated enterprise or financial services environments.Relevant certifications: HashiCorp Certified Terraform Associate, Microsoft Azure Administrator/DevOps Engineer Expert, or MCSE.Exposure to configuration management tooling such as Ansible or NinjaOne.