3rd Line Support Engineer
🛠️ 3rd Line Support Engineer (Onsite) | Enterprise Infrastructure
💷 £50,000 – £60,000 DOE
📍 Onsite – London
Are you a senior support engineer who enjoys being the go-to technical expert on site , rather than sitting in endless ticket queues?
This 3rd Line Support Engineer role places you onsite with a high-profile infrastructure client in London, acting as the highest technical escalation point . You’ll work hands-on with complex technical issues while also contributing to project work, service improvement initiatives, and the development of junior engineers.
You’ll gain exposure to large-scale, enterprise environments, have genuine technical ownership, and be part of a team that values quality delivery, progression, and professional development.
🚀 What You’ll Be Doing
- Acting as the senior onsite escalation point for complex technical incidents
- Owning investigation, diagnosis, and resolution of 3rd line issues
- Supporting and managing internal infrastructure alongside ad-hoc project work
- Providing technical leadership through mentoring and guidance of junior engineers
- Managing client expectations through clear, professional communication
- Ensuring incidents, changes, and time entries are accurately logged
- Maintaining and updating technical documentation as environments evolve
- Working closely with the Service Delivery Manager to align on service standards
- Supporting continuous service improvement and wider team objectives
🧠 What We’re Looking For
- Proven experience working onsite at a client premises in a senior support capacity
- Strong hands-on experience with Microsoft Exchange and Microsoft 365
- Advanced networking knowledge (TCP/IP, routing, switching, NGFWs)
- VPN experience (site-to-site and remote access)
- Virtualisation expertise, ideally VMware in highly available environments
- SAN and storage technologies (iSCSI, SAN administration)
- Strong Microsoft Azure experience, including:
- Entra ID
- Enterprise Applications
- App Services
- Azure SQL
- Deep knowledge of Active Directory, DNS, DHCP, and Group Policy
- Administration of SharePoint Online, Teams, and OneDrive
- Confident communicator with the ability to lead and mentor
💡 Why This Role?
- Senior onsite role with real technical authority
- Exposure to complex, enterprise-scale environments
- Structured learning and development pathways
- Ongoing access to technical training and certifications
- Supportive team culture with clear progression opportunities
- Comprehensive benefits package
📩 Interested?
If you’re looking for onsite ownership, technical depth, and long-term progression, I’d be happy to have a confidential conversation.