IT Technician Tier 3 – Senior Systems & Network Engineer

As an onsite Tier 3 Senior Systems & Network Engineer, you will serve as the highest level of technical escalation within the IT department. This role carries a dual mandate: maintaining the reliability, performance, and security of existing infrastructure, and engineering new solutions that support business growth and modernization. You will handle complex technical issues that cannot be resolved by Tier 1 or Tier 2 support while simultaneously architecting and deploying next-generation infrastructure. Networking is a core competency for this role — you will own and evolve the organization’s network environment alongside Windows Server, Microsoft Azure, Intune, infrastructure monitoring platforms, and line-of-business application maintenance.

Responsibilities

• Act as the highest escalation point for infrastructure, system, and network issues
• Maintain, support, and continuously improve existing server, network, and endpoint infrastructure
• Engineer and deploy new infrastructure solutions from design through implementation, aligned with business growth and modernization goals
• Own and evolve the organization’s network infrastructure — including firewalls, routers, switches, VLANs, and VPNs — both maintaining current environments and designing improvements
• Troubleshoot and resolve complex technical issues across servers, endpoints, and network systems
• Manage and maintain Windows Server environments and Active Directory infrastructure
• Monitor system and network performance using platforms such as Zabbix; deploy and manage infrastructure monitoring and alerting solutions
• Architect and lead deployment of new infrastructure solutions aligned with business growth and modernization goals
• Own and administer Microsoft Azure and hybrid cloud environments
• Deploy, manage, and maintain endpoint environments using Microsoft Intune
• Support and maintain line-of-business applications, including patching, updates, and vendor coordination
• Support virtualization environments and ensure system availability and performance
• Assist with infrastructure projects, including migrations, deployments, and integrations
• Provide technical guidance and escalation support to Tier 1 and Tier 2 teams
• Maintain technical documentation, network diagrams, and system procedures
• Ensure security best practices, patch management, and system hardening standards are followed
• Evaluate and recommend new technologies to improve infrastructure efficiency and reliability