Are you looking to take the next step in your infrastructure career and play a key role in supporting secure, business‑critical services? You'll be joining a tight‑knit team working within a highly focused environment, helping to keep core systems stable, resilient and continuously improving. This is an opportunity to work hands‑on with infrastructure, investigate complex issues, and contribute to improvements that meaningfully impact operational performance. We work onsite in a secure environment in Portsmouth, supporting a programme with growing technical demands. You'll be surrounded by colleagues who share knowledge, support each other, and take pride in delivering high‑quality work in a mission‑driven setting. Working as part of a 24/7 shift-based support team, you will play a key role in ensuring the effective operation, support, and continuous improvement of business-critical applications. The role will involve incident, problem, request, and change management, with opportunities to contribute to testing, implementation, and operational process development. What you'll be doing: Supporting and managing core IT infrastructure, including networks, servers, storage and operating systems. Managing incidents, problems, requests and changes in a structured, ITIL‑aligned environment. Investigating and resolving technical issues and contributing to root‑cause analysis. Monitoring live services to ensure consistent performance against agreed service levels. Contributing to infrastructure improvements, project activity, testing and release support. Producing and maintaining clear technical documentation to support day‑to‑day operations. What you'll bring: Experience in infrastructure support, system administration or a similar technical operations role. Strong troubleshooting and analytical skills with the ability to resolve complex issues. Awareness of ITIL‑based service management processes. Experience supporting technology in structured, process‑driven environments. Ability to work independently and collaboratively as part of a wider technical team. Eligibility for SC and DV, and willingness to work onsite in a secure environment. It would be great if you had: Experience supporting applications or infrastructure using DevOps or scripted models. Exposure to 24/7 operational support environments. Strong experience in Infrastructure Management Experience across one or more: Networks (WAN/LAN) Servers & Storage Experience contributing to testing, system checks or release processes. Familiarity with producing support documentation and operational guidance. An interest in developing towards DV clearance. If you're interested in this role but not sure if your skills and experience are exactly what we're looking for, please do apply, we'd love to hear from you! Employment Type: Full‑time, Permanent. Location: Portsmouth Hampshire area full time onsite part of a 24/7 shift-based support team. Security Clearance Level: Eligible for SC and DV. Internal Recruiter: Soraya. Salary: £45,000 - £65,000. Benefits: 25 days annual leave with the option to buy additional days, life assurance, pension. Although this role is advertised as full‑time, we believe that flexibility at work can promote work/life balance, increase your motivation, reduce stress and improve performance and productivity. We support different ways of working and can offer a range of flexible working arrangements. So, if you're interested and need to work flexibly, we encourage you to apply and talk to us about what might be possible. Loved reading about this job and want to know more about the sector? Sopra Steria's Aerospace, Defence and Security business designs, develops and deploys digital solutions to Central Government clients. The work we do makes a real difference to the client's goal of National Security, and we operate in a unique and privileged environment. We are given time for professional development activities, and we coach and mentor our colleagues, sharing knowledge and learning from each other. We foster a culture in which employees feel valued and supported and have pride in their work for the customer, delivering outstanding rates of customer satisfaction in the UK's most complex safety‑ and security‑critical markets. We embrace difference as a source of creativity, innovation and competitive advantage and are striving to become a more diverse organisation. We welcome applications from people with a diverse variety of backgrounds and identities. We are committed to equality of opportunity for all and do not discriminate on the basis of race, religion, colour, gender, age, disability, sexual orientation or marital status. We have partnered with Vercida, the UK's largest diversity and inclusion focused careers site, where all our vacancies are available in an accessible format. If you require any adjustments to the recruitment process, to enable you to perform to the best of your ability, please let us know when completing your application. We participate in the Disability Confident scheme and are committed to offering an interview to any candidate with a disability, who meets the minimum criteria for the role. If you believe this could apply to you, please let us know when completing your application.