Senior IT Systems Administrator

In 2019, the founders were working as engineers solving complex cross-domain problems within government organisations.

Twin Streamwas formed to bring together their collectiveexpertiseand experience into a single business, focused on delivering technical excellence and high‑quality service to clients.

Since then, the company has grown to over 100 team members across the UK, with colleagues working both on‑site with clients, hybrid and remotely from home.

Salary: £50,000 - £60,000
Location: Bristol (3 days a week)
Security Clearance: Must be eligible for DV Clearance

As a Senior IT Systems Administrator, you’ll take senior operational responsibility for the performance, resilience, maintenance and continual improvement of Twin Stream’s IT systems and services, helping ensure they remain secure, reliable and fit for purpose as the business grows.

Working within the strategy, architecture, standards and technical priorities set by the IT Technical Lead, you’ll translate agreed priorities into well‑planned and sustainable improvements across the corporate IT estate. This is a hands‑on senior role requiring sound technical judgement, leadership of complex technical implementation, resolution of high‑impact issues and guidance for colleagues across the IT team.

You’ll operate autonomously within agreed technical guardrails and delegated authority, escalating significant architectural, strategic or cross‑estate decisions to the IT Technical Lead.

• Leading the day‑to‑day management of the operational performance, resilience and lifecycle of cloud services, corporate infrastructure, end‑user devices and applications.
• Implementing, maintaining and recommending improvements to operational standards for identity and access management, Joiner, Mover and Leaver processes, endpoint management and asset management.
• Leading the technical implementation of configuration changes, automation and system integrations in accordance with agreed architecture, standards and change priorities.
• Administering and optimising cloud platforms, corporate SaaS applications, collaboration tools and development‑support services, escalating material architecture, supplier or licensing decisions where required.
• Providing senior administration and operational assurance of the corporate network, including routers, switches, wireless services and associated network components.
• Monitoring service health, capacity, performance and security, identifying trends and taking proactive action to address risks before they affect users.
• Acting as the senior operational escalation point for complex incidents and problems, coordinating resolution, root‑cause analysis and preventative action, and escalating critical or systemic issues to the IT Technical Lead.
• Planning and coordinating patching, vulnerability remediation and upgrades, balancing operational risk and business priorities within agreed technical and security requirements.
• Implementing, maintaining and testing backup, recovery and continuity arrangements in support of the disaster recovery approach defined by the IT Technical Lead.
• Leading technical investigation and escalation of security events and incidents in accordance with agreed procedures, ensuring corrective actions and lessons are followed through.
• Maintaining the quality of technical documentation, operational procedures, asset information and system records, ensuring they remain accurate and usable.
• Mentoring colleagues, reviewing implementation approaches for alignment with agreed standards and promoting consistent, high‑quality delivery.
• Identifying and analysing operational and technical improvements, distinguishing between service requests, small works and larger changes, and producing options,…