Senior Engineer Infrastructure Operations Linux PAYE Rate: £469.98 per day Umbrella Rate: £602.83 per day Contract | Inside IR35 Duration: 6 months initially (with potential extensions) Hybrid Milton Keynes (approx. 60% onsite) Were supporting a high-profile government-aligned organisation delivering secure, mission-critical infrastructure services. They are looking for an experienced Senior Infrastructure Engineer (Linux SME) to join their specialist infrastructure team. This is a hands-on role operating within a secure, enterprise-scale environment where stability, performance and security are paramount. The Role As a Linux Subject Matter Expert, you will: Provide expert-level support across enterprise Linux platforms Maintain and enhance secure, assured infrastructure environments Support both BAU operations and project-based deliverables Lead conversations around infrastructure automation and environment growth Build and maintain development environments Containerise applications and services Support modern deployment approaches alongside traditional platform operations Work closely with cross-functional infrastructure specialists Produce and maintain high-quality operational documentation Contribute to knowledge transfer across the team Youll be operating within structured service management and security frameworks, so experience in highly regulated environments is essential. Required Experience Strong Linux system administration (enterprise level) Experience supporting secure production platforms Containerisation experience (e.g. Docker or similar) Building and maintaining development environments Automation and infrastructure improvement initiatives Working within formal IT service management frameworks Strong troubleshooting and performance optimisation skills Desirable Certifications One or more of the following: RHCSA (Red Hat Certified System Administrator) RHCE (Red Hat Certified Engineer) LFCS (Linux Foundation Certified System Administrator) LPIC-1 or LPIC-2 Security & Eligibility Due to the nature of the work: You must be a British national (single or dual nationality) You must have resided in the UK for at least 2 of the last 5 years You must be eligible to obtain SC (Security Clearance) Clearance does not need to be held currently, but you must be able to pass vetting (68 week process). Working Arrangements Hybrid role minimum 60% onsite at Hanslope Park (Milton Keynes) Occasional travel within London/Milton Keynes area Standard professional working week (37.5 hours) On-call rota participation required Minimum 6 shifts per 28-day cycle Flat fee paid per shift This is an opportunity to work within a highly secure, nationally significant environment where infrastructure resilience and security truly matter. If this role is of interest and you meet the above criteria, then please apply immediately.