Security & Infrastructure Engineer (Freelance)

About the role

We are seeking a Security & Infrastructure Engineer on a freelance basis to support a public research and technology centre in Luxembourg. The main focus will be the remediation and hardening of its Active Directory environment following recent security assessments, ensuring a robust and secure enterprise infrastructure.

Key responsibilities

• Analyse the current Active Directory architecture and identify security gaps.
• Implement AD hardening measures and tiered administration models.
• Manage and secure LDAP/LDAPS, SMB signing, and DNS configurations.
• Define, document and support backup and recovery procedures.
• Contribute to broader enterprise infrastructure security improvements.
• Assist with operational hand‑over and the implementation of best‑practice processes.

Required profile

• Strong expertise in Active Directory security and architecture.
• Hands‑on experience with LDAP/LDAPS, SMB signing and DNS security.
• Proven knowledge of AD hardening and tiered access models.
• Experience designing backup and recovery strategies for enterprise environments.
• Background in enterprise infrastructure and security contexts.
• Fluent English communication skills.

Required skills

• Active Directory
• LDAP/LDAPS
• SMB signing
• DNS security
• AD hardening
• Backup and recovery procedures
• Enterprise infrastructure security

What we offer

• On‑site work at the Esch‑sur‑Alzette location.
• Part‑time freelance contract.
• Competitive salary based on experience.