Senior 3rd-Line IT Engineer: Client Infrastructure Lead

Speedster-IT Ltd; Greater London; Hybrid; GBP 50,000 - 70,000; Full time

Job summary

Speedster IT seeks a Senior Engineer 3rd Line in London to own the day-to-day health of client IT environments, from servers to cloud services. This hands-on, client-facing role requires strong technical depth and the ability to collaborate with vendors and internal teams.

You will troubleshoot complex issues, deploy changes, maintain security tooling, and document configurations and incident reports to keep knowledge bases current.

Qualifications

• Proven experience at 2nd or 3rd line in an MSP environment.
• Strong knowledge of Windows Server, Active Directory, and networking fundamentals.
• Experience with Microsoft 365, Azure, and cloud-based infrastructure.
• Confident working with firewalls, switches, and security tooling.
• Clear written and verbal communication — with both technical and non-technical audiences.
• A methodical approach to troubleshooting with thorough documentation habits.

Responsibilities

• Provide hands-on support for client IT environments including servers, networks, and end-user systems.
• Monitor and maintain internal and external networks, email platforms, and security systems.
• Proactively identify and address risks before they impact client operations.
• Configure and deploy new server systems, hardware, and software in client environments.
• Carry out scheduled maintenance including patch management, updates, and backup and recovery operations.
• Manage system restarts and recovery procedures following outages or failures, minimising downtime at every stage.
• Diagnose and resolve complex technical faults escalated from 1st and 2nd line support.
• Where issues fall outside your remit, elevate to senior engineers or third-party vendors with thorough documentation of all steps taken.

Skills

3rd line support MSP experience

Windows Server

Active Directory

Networking fundamentals

Microsoft 365 / Azure

Security tooling / firewalls

Tools

ConnectWise

Datto

NinjaRMM

Job description

Speedster IT seeks a Senior Engineer 3rd Line in London to own the day-to-day health of client IT environments, from servers to cloud services. This hands-on, client-facing role requires strong technical depth and the ability to collaborate with vendors and internal teams.

You will troubleshoot complex issues, deploy changes, maintain security tooling, and document configurations and incident reports to keep knowledge bases current.