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Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Infrastructure & Security Engineer - **Company:** Oritain - **Location:** London, UK - **Experience:** Expert - **Contract:** Permanent contract - **Skills:** Microsoft Windows, Artificial Intelligence, Microsoft Antivirus, User Authentication, Microsoft Azure, Cloud Computing, Cyber Security, Information Leak Prevention, Intrusion Detection and Prevention, Virtual Private Networks (VPN), Network Security, Networking Basics, Network Planning and Design, Routing, Role-Based Access Control, Azure Active Directory, Microsoft Copilot, Zero Trust Network Access, Security Information and Event Management, Systems Integration, Virtual Local Area Networks, Software Vulnerability Management, Wide Area Networks, Wireless Networks, Information Security Management System, Firewalls (Computer Science), Information Technology, Microsoft Sentinel, Claude, Artificial Intelligence Governance, Firewall Services Module - **Published:** October 16, 2026 - **Apply:** https://www.indeed.com/viewjob?jk=6cd6af1133b25e71 ## About the Role You'll bring senior, hands-on experience delivering and supporting IT infrastructure and security, ideally in an organisation of a similar size with global reach, or larger. Most importantly, you'll have a track record of taking a broad security objective, defining the approach and delivering it end to end with minimal direction. Technically, you'll have strong working knowledge of Microsoft Entra ID, identity and access management and secure authentication, alongside practical experience with Azure and Microsoft 365 infrastructure, including Microsoft Defender and Sentinel. You'll have solid networking fundamentals, including VLANs, switches, firewalls, routing and VPNs, and experience supporting security incident response and vulnerability management. You'll also have working knowledge of security frameworks such as ISO 27001, NIST and Cyber Essentials, with experience supporting audits, ISMS activities or compliance tooling such as Vanta. You'll communicate clearly and feel confident working with, influencing and supporting both technical and non-technical colleagues. Above all, you'll bring energy, curiosity and real ownership, with the openness to share ideas, take feedback and keep learning. It would be great if you also have Experience with Zero Trust architectures beyond baseline identity and access controls, advanced security monitoring, detection engineering or SIEM tuning, or automation and scripting would be a real advantage. We'd also value exposure to enterprise AI tooling beyond standard end-user use, experience with SASE or cloud-based SD-WAN platforms, and relevant Microsoft, Azure, networking or security certifications. ## Description We're looking for an Infrastructure & Security Engineer to take ownership of the security and infrastructure foundations that support Oritain's growth. Reporting to our Head of IT & Security, you'll secure our cloud, identity and network environments and play a central role in maturing our compliance programme through ISO 27001 renewal, Cyber Essentials certification and alignment with the NIST and CMMC frameworks. This is a senior, hands-on role for someone who thrives taking on a task, shaping the plan, bringing the right people together and delivering it. In your first months, around half of your time will focus on strengthening our security posture, so you'll make a visible impact early. You'll work closely with our Service Desk, Engineering teams and colleagues across the business. While there are no direct reports, you'll be a leading voice in the team: drawing in colleagues to deliver projects, guiding others on how to build securely and helping shape how we work. You'll also lead the secure adoption of AI across Oritain, bringing an AI-first approach to how we run and protect our infrastructure. We're a fast-growing business, and many of our processes are still being built. If you see that as an opportunity to create structure, raise standards and leave your mark, you'll find real scope to grow here, including the chance to build expertise in our modern cloud-based networking and security platform., Your core focus will be the security of our infrastructure and platforms. You'll identify, track and remediate vulnerabilities, stay ahead of patching priorities, and administer and continuously improve Microsoft Defender and Microsoft Sentinel, integrating infrastructure and security tooling for monitoring and detection. When incidents happen, you'll coordinate and technically lead the response alongside our external Security Operations Centre (SOC). You'll drive our compliance and accreditation work for ISO 27001, Cyber Essentials, NIST and CMMC, using Vanta to manage control coverage and evidence collection. You'll also contribute to the ongoing development of our Information Security Management System (ISMS) and conduct third-party risk assessments, using automation, Vanta and AI to work efficiently. On the infrastructure side, you'll design, build, secure and improve our cloud and on-premises services. This includes delivering identity and access solutions with Microsoft Entra ID, Conditional Access, role-based access control and secure authentication, and administering Azure infrastructure such as VNets, routing, VPN and site-to-site gateways, and network security groups. You'll design network segmentation using VLANs, firewall rules and access controls, build and troubleshoot SD-WAN technologies, and support wired and wireless networking, including RADIUS and certificate-based authentication. You'll also lead the secure adoption of AI across Oritain. That means designing, deploying and securing tools such as Microsoft Copilot and Claude, with data loss prevention (DLP) and Purview controls across Microsoft 365 and Azure. You'll define AI guardrails, governance standards and usage policies, assess risks such as data leakage and regulatory exposure, and apply AI and automation to make our infrastructure and security workflows more efficient.