Senior IT Infra Engineer

Our client is a leading mobile network operator that runs Singapore's connectivity. The IT team is lean and senior, meaning less bureaucracy, more ownership. This is a hands-on role across network engineering, systems, cloud, and security, working closely with the Cybersecurity team in a compliance-driven environment. Responsibilities Design and administer network infrastructure - routing, switching, firewalls, VPNs, NAC, wired and wireless Manage Windows Server, Linux, and virtualisation platforms (VMware, Hyper-V), including NAS, SAN, and vSAN Administer M365 services (Entra ID, Intune, Exchange Online, Teams) and hybrid AD/Entra identity Own monitoring tools (Grafana, Zabbix, PRTG, Nagios), patching cycles, migrations, and documentation Enforce security best practices - segmentation, CIS hardening, PAM/IAM control Implement M365 security controls, audit logging, and ensure regulatory compliance Operate across incident, problem, and change management within ITSM frameworks Requiremen...