Senior Infrastructure / Linux Security Engineer

ATS4IT supports its clients in their digital transformation initiatives and AI driven innovations, in different sectors and it's a part MoOngy Group, with over 9,500 employees across Europe, we bring extensive expertise across a wide range of IT domains. With teams in Belgium, Denmark, and a nearshore center in Portugal, we deliver proximity, agility, and real impact across Europe.

Senior Infrastructure / Linux Security Engineer

Location: Brussels (Hybrid)

Languages: C2 English

Nice to Have: French
--> Due to project-specific security and compliance requirements, only EU citizens are eligible to apply for this position .

About the Role

We are looking for an experienced Senior Infrastructure / Linux Security Engineer to join a dynamic team responsible for securing, maintaining, and evolving critical Linux-based infrastructure environments. The ideal candidate combines strong expertise in Linux administration, infrastructure security, vulnerability management, automation, and cloud technologies, with a proactive approach to ensuring system reliability and security.

Profile

• Bachelor's or Master's degree in Computer Science, Cybersecurity, Information Technology, or a related field.
• More than 10 years of experience in Infrastructure Engineering, Linux Administration, or IT Security.
• Strong analytical and troubleshooting skills.
• Excellent communication and collaboration abilities.
• Ability to work effectively in Agile and cross-functional environments.
• Security-focused mindset with a commitment to continuous improvement and operational excellence.

Requirements

Mandatory

• 10+ years of experience in Linux Infrastructure and Security.
• Strong expertise with Red Hat Enterprise Linux (RHEL) and Linux system administration.
• Experience with system hardening, vulnerability management, and patch management .
• Strong knowledge of Identity & Access Management (IAM) concepts.
• Experience with SIEM solutions , log analysis, and security monitoring.
• Good understanding of network security , firewalls, and secure communication protocols.
• Experience with shell scripting and automation.
• Knowledge of security frameworks and compliance standards.
• Experience investigating and resolving security incidents.

Strongly Preferred

• Experience with Microsoft Defender , CrowdStrike , Splunk , Elastic, or similar security platforms.
• Experience with Docker and container security.
• Experience working with AWS and/or Azure environments.
• Knowledge of Ansible , Terraform , or Infrastructure-as-Code practices.
• Experience with endpoint protection and vulnerability assessment tools.
• Knowledge of Zero Trust and modern security architectures.

Nice to Have

• French language skills.
• Security certifications such as Security+ , CISSP , CEH , or equivalent.
• Experience with Kubernetes security.
• Experience in highly regulated or enterprise environments.

Key Responsibilities

• Manage, secure, and optimize Linux-based infrastructure environments.
• Monitor security events and investigate potential threats and incidents.
• Implement security controls, hardening standards, and vulnerability remediation plans.
• Maintain patching and update processes across infrastructure platforms.
• Automate operational and security-related tasks.
• Collaborate with infrastructure, cloud, and security teams to improve platform resilience.
• Support security audits, compliance initiatives, and risk assessments.
• Contribute to incident response and root cause analysis activities.
• Improve monitoring, logging, and threat detection capabilities.
• Promote security best practices across the organization.

Technical Environment

• Red Hat Enterprise Linux (RHEL)
• Linux Administration
• IAM
• SIEM
• Splunk / Elastic
• Microsoft Defender
• CrowdStrike
• Vulnerability Management
• Docker
• Bash / Shell Scripting
• Ansible / Terraform
• AWS and/or Azure
• Security Monitoring & Incident Response
• Agile/Scrum

What We Offer

• Permanent Contract (CDI) – Long-term stability.
• Attractive salary based on your experience and skills.
• Additional benefits: Meal vouchers and eco-vouchers (electronic), DKV hospitalization insurance, company laptop, holiday allowance, and year-end bonus.
• Free training (technical, behavioral, language) and certifications.
• Continuous and personalized career progression support.
• Opportunities to work on projects with cutting-edge technologies.

At Moongy Group, we stand for equality and diversity. We create a safe and inclusive environment where opportunities are equal for everyone! We do not discriminate based on age, ethnicity, gender, disability, sexual orientation, or any factor other than merit. If you have the skills for the role, we encourage you to apply!