Linux Infrastructure Engineer

Linux Infrastructure Engineer £480 P/D OUTSIDE IR35 6 MONTH CONTRACT We're looking for a hands-on Infrastructure Engineer to join our engineering team and take ownership of production infrastructure across Linux, networking, physical servers, automation and infrastructure security. This is an engineering-focused role for someone who enjoys understanding how systems work, getting close to the underlying infrastructure and solving complex problems at root cause level. Our environment is primarily self-managed, dedicated and bare-metal infrastructure, rather than public cloud. You'll work across production Linux servers, dedicated hosting and colocation environments, physical hardware, networking, monitoring, automation and security. Security is an important part of the role, with responsibilities spanning encryption, secrets management, key management, PKI and certificate lifecycle management. What you'll do

• Manage and maintain Ubuntu Linux servers in production, including systemd, processes, filesystems, package management, logging and system troubleshooting.
• Operate infrastructure across dedicated hosting providers such as Hetzner and OVH, as well as colocation environments and data centres.
• Configure, troubleshoot and maintain routing, DNS, firewalls and VPNs.
• Work directly with physical infrastructure, including diagnosing and resolving hardware failures.
• Investigate production incidents and technical problems, focusing on root cause rather than symptoms.
• Plan and implement infrastructure changes with a clear understanding of system dependencies and production impact.
• Automate infrastructure management using scripting, Ansible and configuration management.
• Use metrics, dashboards, alerts and logs to understand system health, identify issues and improve observability.
• Assess the security implications of infrastructure changes, including vulnerability remediation, access control and secrets management.
• Translate security and compliance requirements into practical, maintainable infrastructure controls.
• Contribute to the design and implementation of encryption, key management and certificate lifecycle processes.
• Work closely with software engineers and other technical teams, asking questions early and challenging assumptions where appropriate.
• Help improve the reliability, security and operational maturity of our infrastructure over time. What we're looking for
• 5+ years of experience in infrastructure, systems engineering, platform engineering or a closely related discipline.
• Strong hands-on experience managing Ubuntu/Linux production environments.
• Solid understanding of Linux fundamentals, including systemd, processes, filesystems, packages and logs.
• Experience operating dedicated servers, bare-metal infrastructure and/or colocation environments.
• Strong networking fundamentals, including routing, DNS, firewalls and VPNs, with the ability to troubleshoot issues methodically.
• Experience working with physical servers and diagnosing hardware problems.
• Strong troubleshooting and analytical skills, with a focus on finding and fixing root causes.
• Good understanding of system dependencies and how to safely plan and implement production changes.
• Experience with Ansible and scripting for infrastructure automation.
• Experience with monitoring and observability, including metrics, dashboards, alerts and logs.
• A strong understanding of infrastructure security, including vulnerability management, access control and secrets handling.
• Ability to turn compliance and security requirements into real-world technical controls.
• A collaborative approach and the confidence to work closely with developers and raise concerns or questions early. Desirable experience You don't need to have experience with everything below, but exposure to several of these areas would be highly valuable:
• Operating a large fleet of servers, potentially hundreds of hosts.
• ZFS and Linux storage technologies.
• WireGuard and private network design.
• KVM/QEMU virtualisation.
• VictoriaMetrics, Grafana and ELK or similar observability platforms.
• Ability to read and understand Go code.
• Rootless containers, particularly Podman.
• CoreDNS and Cloudflare.
• Terraform and Kubernetes.
• Encryption at rest and encryption in transit.
• Automated key generation, storage and rotation.
• Automated certificate issuance, renewal, rotation and revocation as part of Certificate Lifecycle Management (CLM).
• PKI (Public Key Infrastructure) and certificate authorities.
• Implementing infrastructure security controls and applying security best practices.
• Enterprise certificate lifecycle management platforms.
• Self-hosted key management systems and automated key rotation.
• Secrets management tools such as SOPS, OpenBao/Vault or AWS Secrets Manager.
• Disk and filesystem encryption on Linux hosts.
• Automating certificate renewal and deployment for services running on Linux.
• Security frameworks and audits such as ISO 27001 or SOC 2.