Sr. IT System & Network Administrator​/Administrateur principal ou Administratrice principale, systèm

Reporting to the Infrastructure Manager, the Sr. IT System & Network Administrator is a senior technical and delivery-focused role responsible for architecting, implementing, and evolving on‑premise, hybrid, and cloud-based infrastructures. This role goes beyond day‑to‑day administration and acts as a technical lead for complex infrastructure initiatives, with full end‑to‑end responsibility including analysis, design, implementation, documentation, knowledge transfer, and operational handover.

The Sr. IT System & Network Administrator is expected to demonstrate strong leadership in cloud platforms, infrastructure as code, security best practices, and cross‑functional project coordination. They serve as a technical reference for Infrastructure and Support teams while ensuring that infrastructure solutions align with business, security, and compliance requirements.

• Design, deploy, and manage cloud and hybrid infrastructures (IaaS, PaaS, hybrid connectivity) aligned with business and security requirements.
• Lead architecture decisions related to cloud networking, identity, access management, backup, disaster recovery, monitoring, and cost optimization.
• Define and enforce infrastructure standards, naming conventions, network segmentation, and security baselines across cloud and on‑prem environments.
• Ensure high availability, scalability, performance, and resilience of critical systems.
• Own infrastructure projects from initiation to closure, including requirements gathering, solution design, effort estimation, risk identification, execution, and post‑project review.
• Act as the technical project lead for infrastructure initiatives involving internal teams and external partners.
• Coordinate dependencies across Infrastructure, Helpdesk, Security, Development, and third‑party vendors.
• Ensure deliverables meet scope, quality, timeline, and documentation expectations.

• Administer and optimize complex server, storage, virtualization, and network environments.
• Lead implementation of advanced networking concepts (segmentation, firewalls, VPNs, secure remote access, multi‑site connectivity).
• Oversee identity and access management solutions, including MFA and privileged access controls.
• Drive automation initiatives for provisioning, monitoring, configuration management, and reporting.

• Integrate security best practices into infrastructure design and operations (zero trust principles, least privilege, secure configurations).
• Support compliance requirements from external regulators, certifications, and regional authorities.
• Define and test backup, disaster recovery, and business continuity strategies.
• Proactively identify risks, technical debt, and opportunities for infrastructure improvement.

• Produce clear, structured, and reusable documentation for architectures, deployments,procedures, and operational runbooks.
• Ensure a smooth transition of delivered solutions to operations and support teams.
• Mentor and provide technical guidance to junior administrators and analysts.
• Contribute to the continuous improvement of IT standards, tools, and operating practices.

• DEC or higher education in Computer Science or equivalent experience.
• Professional certifications in cloud or infrastructure technologies are considered an asset.
• 7+ years of experience in system and network administration, with progressive responsibility in complex environments.
• Strong experience with cloud platforms and hybrid infrastructures.
• Excellent knowledge of networking concepts, firewalling, routing, segmentation, and secure connectivity.
• Advanced knowledge of Windows server environments and modern infrastructure services.
• Experience with automation, scripting, or infrastructure‑as‑code concepts.
• Solid understanding of monitoring, backup, disaster recovery, and high‑availability architectures.
• Strong analytical and problem‑solving skills with a structured approach to delivery.
• Ability to communicate technical concepts clearly to both technical and non‑technical stakeholders.
• Excellent organizational and documentation skills with strong attention to detail.
• Ability to work autonomously while collaborating effectively across teams.
• Fluent in French and English, both spoken and written.