Freelance Senior Infrastructure Engineer – Virtualization & WindowsContract until end 2026, renewable, Diegem- Hybrid (3 days onsite) – intention to move to full-time onsite as of January 2027Overall Role PurposeWe are looking for a highly motivated Senior Infrastructure Engineer. In this role, you will help manage and evolve a complex, global environment covering Windows Server, Active Directory, VMware vSphere and Nutanix, with a strong focus on availability, security, performance and disaster recovery.The ideal candidate brings solid hands-on experience in enterprise infrastructure environments and enjoys working in an international, mission-critical context.ResponsibilitiesDesign, implement and manage VMware, Nutanix and Windows Server infrastructure to ensure high availability and optimal performanceMonitor and proactively optimize performance across VMware vSphere, Nutanix and Windows Server environmentsIdentify, troubleshoot and resolve complex infrastructure issuesPlan and execute system updates, patches and upgrades with minimal operational impactDevelop and maintain clear, structured documentation of processes, procedures and configurationsCollaborate closely with other IT teams and stakeholders to align infrastructure solutions with business objectivesStay up to date with industry trends, emerging technologies and security best practicesQualificationsMinimum 5 years of experience in IT Infrastructure administration and configurationProven hands-on experience with VMware vSphere, Nutanix, and virtualization technologies in generalStrong expertise in Microsoft Windows Server, Active Directory Domain Services and related servicesSolid understanding of networking principles and system architectureExperience with automation and scripting, preferably using PowerShell and Ansible (or similar tools)Knowledge of System Center Operations Manager (SCOM) is a plusAwareness of GDPR and IT security standardsStrong communication skills and a collaborative, team-oriented mindsetAble to work independently, under pressure, with strong analytical skillsFluent in English, both spoken and written