Senior Engineer (L3)

This position is listed on behalf of a partner company, who manages all applications and next steps. Our partner is looking for a Senior Engineer (L3) based in United States. This role is an opportunity for an experienced IT professional to take ownership of complex technical escalations in a fast-paced managed services environment. You will serve as a senior technical resource, resolving advanced infrastructure, networking, server, cloud, security, and Microsoft technology issues. The position combines hands-on engineering with direct client communication and technical problem-solving. You will work across diverse client environments while helping improve reliability, documentation, and operational efficiency. Success in this role requires strong technical judgment, independence, and a commitment to delivering high-quality support. You will also have opportunities to expand your expertise through exposure to a broad range of enterprise technologies. Own escalated L3 technical tickets from assignment through complete resolution, taking responsibility for complex issues that cannot be resolved at lower support levels. Diagnose and resolve advanced problems across Windows Server, Active Directory, Exchange, Microsoft 365, Entra ID, Azure/AWS, virtualization, networking, security, backup, and other infrastructure technologies. Administer and troubleshoot Windows Server environments, Active Directory, Group Policy, DNS, DHCP, authentication, domains, permissions, Exchange, Microsoft 365, Teams, SharePoint, OneDrive, Intune, Conditional Access, and MFA. Configure and troubleshoot enterprise networking technologies, including TCP/IP, VLANs, routing, switching, VPNs, DNS, firewalls, wireless networks, routers, and network-connected devices. Support cloud, virtualization, and datacenter environments, including Azure, AWS, Hyper-V, VMware, Citrix, SQL Server, Veeam Backup & Replication, SANs, high-availability solutions, load balancing, and related infrastructure. Support Fortinet and UniFi network environments, as well as endpoint security, EDR/XDR, managed security platforms, and other security technologies. Troubleshoot connectivity and infrastructure issues across workstations, servers, networks, firewalls, ISPs, DNS, routing, VPNs, and wireless systems, identifying root causes and implementing effective solutions. Safely execute basic PowerShell and command-line scripts and use technical expertise to investigate issues across interconnected systems. Maintain detailed technical documentation covering troubleshooting steps, client communications, actions taken, root causes, resolutions, and relevant environment changes. Communicate clearly with clients, end users, IT teams, Account Managers, leadership, and C-level stakeholders, providing accurate next steps, ETAs, and technical explanations. Identify recurring technical problems and recommend improvements that reduce repeat incidents and strengthen service reliability. Work independently while escalating appropriately when additional technical expertise or resources are required. Participate in technical training, knowledge sharing, after-hours support, and on-call coverage for urgent or client-impacting issues as needed. Requirements: Minimum 5 years of professional engineering or equivalent technical experience, including substantial hands-on experience supporting complex IT environments. At least 5 years of experience with Active Directory, Microsoft Windows, Windows Server, and Microsoft 365. At least 5 years of experience with network switching, VLANs, routing, firewalls, VPNs, backup and recovery, endpoint security, and related infrastructure. Strong knowledge of Microsoft Windows, Windows Server, Active Directory, Exchange, Microsoft 365, and enterprise networking technologies. Working knowledge of Microsoft Azure and/or Amazon AWS, Microsoft Entra ID, Conditional Access, MFA, Intune, and cloud identity management. Working knowledge of SQL Server, Veeam Backup & Replication,