We’re looking for an experienced Senior System Administrator to join our Infrastructure team on a contract basis, helping us keep Reward’s IT estate stable, secure, and scalable as we continue to grow.
You’ll play a key role in supporting and evolving the infrastructure that underpins our business from office networks and data centres to Microsoft 365, Intune, and endpoint management supporting 200+ employees across the organisation.
This is a hands on, infrastructure heavy role, ideal for someone who enjoys ownership, problem solving, and working across a broad range of technologies in a fast-moving environment.
🛠 What you’ll be doing
* Working onsite in our London office 3 days per week (rota with the team)
* Providing ad-hoc support to our Belfast office when required
* Owning and supporting office networks (LAN & Wi‑Fi) design, build, performance and troubleshooting
* Managing firewalls: rules, NAT, segmentation, VPNs and firmware
* Supporting switching and core network services (VLANs, routing, redundancy)
* Maintaining network architecture standards, DNS/DHCP and capacity planning
* Supporting our on prem / data centre server estate (hardware, OS, lifecycle, upgrades)
* Attending the central London data centre as needed for installs, upgrades and BAU support
* Executing patching, backups, monitoring and alerting, with a focus on reliability and compliance
* Administering Microsoft 365 and Intune (policies, baselines, deployments)
* Improving tooling, dashboards, documentation and operational processes
* Supporting and collaborating with junior and mid level SysAdmins
* Providing out-of-hours support where required (on call may follow)
* Assisting with desktop support via Zendesk to keep day to day operations running smoothly
* Helping maintain PCI‑DSS and ISO27001-aligned security standards
👀 What we’re looking for
* Strong hands‑on experience with networks: LAN/Wi‑Fi, TCP/IP, DNS, DHCP, VLANs, routing & VPNs
* Solid firewall management experience (rules, NAT, segmentation)
* Excellent hardware and infrastructure troubleshooting skills
* Strong experience with switching, routing, uplinks and redundancy
* Practical experience supporting Microsoft 365 and Intune
* Experience in on‑prem environments and data centre operations
* Confident managing backups, restores and retention
* Comfortable working with servers, networking components and infrastructure services
* Clear communicator with both technical and non‑technical stakeholders
* Proactive, detail‑oriented and comfortable working autonomously
* Happy operating in a high‑change environment with evolving processes
🌟 Nice to have
* Advanced Excel (PowerPivot, VBA, complex formulas)
* Python for automation or data wrangling
* Exposure to cloud technologies
* Experience with Power BI or Tableau
* Familiarity with AWS governance and compliance
* Background in retail, banking, CRM, loyalty or digital marketing
* Degree in Computer Science, Engineering, Mathematics or similar
* A genuinely hands‑on infrastructure‑first contract role
* Exposure to a broad, modern tech estate
* Opportunity to help shape standards, tooling and best practices
* Collaborative team with real ownership and impact
If you’re a proactive SysAdmin who enjoys variety, responsibility, and improving how things work apply now!
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