Our client operates a high-security engineering hub that supports defense-grade programs, with teams responsible for the secure operation of hybrid information systems used by NATO stakeholders. 

You’ll join a group that values operational excellence, clear runbooks, and continuous knowledge transfer.

The role

We’re hiring a System Security Infrastructure Engineer at L3 level to lead day-to-day security operations and coach administrators across a hybrid CIS landscape. 

You’ll own major incidents and complex changes, keep SOPs aligned with evolving standards, and act as the primary point of contact for NATO on SSI matters - ensuring compliance, audit readiness, and smooth communication between engineering and security.

Key responsibilities:

• Provide L3 support across SSI: configure and update security solutions, monitor logs/alerts, investigate and respond to incidents, and manage vulnerabilities and patching; deliver clear security reporting;

• Coach and uplift SSI/IT admins; contribute training materials and courses; maintain accurate SOPs and technical documentation;

• Liaise with the project information system security lead to ensure controls are effective and documented end-to-end.

To thrive in this role, you will:

• Bring strong SSI expertise (senior level) and solid grounding in Windows/AD/DNS/NTP and core services such as DHCP, NPS, SCCM;

• Be hands-on with firewalls and threat controls (Fortinet or Palo Alto/Panorama; IPS/IDS, DPI, anti-malware, IPsec), plus Cisco networking (VLANs, routing). Bastion access management (Wallix) experience is expected;

• Demonstrate senior capability with PKI/keys/certificates and endpoint security (Trellix), along with log management across OS/AD/network/ESXi;

• Manage backups and restores using Commvault/Veeam; perform vulnerability scanning (e.g., Nessus); and automate with Ansible and Git.

• Operate within ITIL: intermediate in Incident/Change/Problem, senior in Security Management;

• Fluent English communication.