Senior System Administrator Job ID JP054241

We are looking for a Senior System Administrator to support and modernize critical IT infrastructure within a highly secure and technically advanced environment. You will work in a multidisciplinary team responsible for maintaining reliable server environments virtualization platforms and infrastructure services while contributing to system evolution and operational excellence.

• Administer and maintain Windows and Linux server environments
• Manage Active Directory GPO DNS DHCP and identity services
• Monitor and optimize virtualization platforms such as VMware Proxmox and Hyper-V
• Ensure infrastructure security patch management backups and business continuity
• Support infrastructure modernization and scalable system architecture design
• Automate operational tasks using PowerShell Bash Python or similar scripting tools
• Troubleshoot and resolve complex infrastructure and system issues
• Collaborate with infrastructure network and security teams
• Maintain technical documentation and operational procedures
• Participate in infrastructure migrations and continuous improvement initiatives

• Minimum 7 years of experience in Windows and Linux system administration
• Strong expertise in virtualization storage and infrastructure security
• Proven experience with Active Directory and large-scale infrastructure environments
• Solid scripting skills (PowerShell Bash Python or equivalent)
• Understanding of networking security and identity management concepts
• Experience with Azure or AWS is considered a plus
• Bachelors or Masters degree in IT or equivalent experience

• Analytical and solution-oriented mindset
• Proactive autonomous and reliable
• Strong communication and documentation skills
• Able to work under pressure in critical environments
• Team player with strong problem-solving abilities

• Dutch or French: native/fluent level
• Good understanding of the second national language
• English: active technical knowledge

• Hybrid role based in Brussels
• Up to 2 remote workdays per week

• Initial contract until end of June 2026
• Second contract until end of 2026 renewable
• A TOP SECRET security clearance is required for this position