Network Security Engineer F5

In4Matic; Brussel; On-site; EUR 90,000 - 120,000; Full time

Job summary

In4Matic is seeking a Senior Network & Security Engineer to own the security, administration and evolution of critical network security infrastructure. This highly autonomous, hands‑on role requires a seasoned security professional who can blend deep technical expertise with structured risk management and incident response.

You will install and optimize F5/AWAF (APM, ASM, LTM, SSL VPN), develop security policies, assess threats, and drive remediation.

Qualifications

• 7+ years of relevant IT security experience; 10+ years preferred.
• Ability to work independently under general direction and own complex technical security matters.
• Proven incident handling and crisis response experience.
• Strong analytical, risk‑assessment and problem‑solving skills.
• Excellent written and verbal communication; produce high‑quality technical documentation.
• Team‑oriented, methodical, precise and client‑focused.
• English is essential; knowledge of French and/or Dutch valued; bilingual a plus.
• Degree in Computer Science, Electronics, IT or related field, or equivalent professional experience.

Responsibilities

• Install, configure, administer and improve F5/AWAF infrastructure (APM, ASM, LTM, SSL VPN).
• Develop, document and monitor security policies and standards.
• Continuously assess the security posture and identify threats, vulnerabilities and weaknesses.
• Conduct technical risk assessments and provide actionable recommendations.
• Implement remediation measures to address vulnerabilities and improve security posture.
• Advise on secure technical solutions for internal and external partner connectivity.
• Contribute to security incident and crisis management, including coordinated attacks and incidents.
• Produce clear and rigorous technical documentation, security assessments and incident/crisis reports.

Skills

F5 / AWAF

Security policies

Threat assessment

Incident response

Vulnerability remediation

Risk management

Technical documentation

Team collaboration

Education

Bachelor's degree in Computer Science / IT or related field

Equivalent professional experience

Tools

Splunk

Nessus

Elastic SIEM

Citrix

Palo Alto / Forcepoint / Panorama

SSL VPN

Job description

We’re looking for a Senior Network & Security Engineer to join our client’s team and take ownership of the security, administration and continuous evolution of critical network security infrastructure. This is a highly autonomous, hands‑on role for an experienced security professional who can combine strong technical expertise with a structured approach to risk management, vulnerability remediation and incident response.

Role & Responsibilities

• Install, configure, administer and continuously improve F5 / Advanced Web Application Firewall (AWAF) infrastructure, including APM, ASM, LTM, Identity Provider and SSL VPN technologies.
• Develop, document and monitor the implementation of security policies and standards.
• Continuously assess the security posture of IT systems and identify potential threats, vulnerabilities and weaknesses.
• Conduct technical risk assessments across different IT environments and provide actionable recommendations.
• Implement remediation measures to address identified vulnerabilities and improve the overall security posture.
• Advise on secure technical solutions for internal and external partner connectivity, including intranet and internet connections.
• Contribute actively to security incident and crisis management, including coordinated attacks, network intrusions, malware/virus incidents and other critical security events.
• Produce clear and rigorous technical documentation, security assessments and incident/crisis reports.

Technical Profile

• F5 / AWAF installation, configuration, administration and troubleshooting.
• Application and network security technologies, including APM, ASM, LTM, Identity Provider and SSL VPN.
• Network and application firewalls, particularly technologies such as Palo Alto, Forcepoint and Panorama.
• VPN and Web Proxy solutions.
• Network security protocols and technologies including TCP/IP, HTTP/HTTPS, SSL and SNMP.
• Security monitoring, log analysis and correlation tools such as Splunk, Nessus and Elastic SIEM.
• Wireless network security, including Wi‑Fi, WEP, WPA/WPA2 and encryption principles.
• Remote‑access and site‑to‑site VPN solutions, Web Proxy technologies and terminal‑server environments such as Citrix.

Experience & Soft Skills

• 7+ years of relevant experience, with approximately 10 years or more in IT security strongly preferred.
• Proven ability to work independently under general direction and take ownership of complex technical security matters.
• Demonstrated experience handling security incidents and operating effectively under pressure during crisis situations.
• Strong analytical, risk‑assessment and problem‑solving capabilities.
• Excellent written and verbal communication skills, with the ability to produce high‑quality technical documentation and communicate effectively with both technical teams and management.
• Team‑oriented, methodical, precise and client‑focused.
• English is essential for technical communication; knowledge of French and/or Dutch is highly valued, with bilingual proficiency in French and Dutch considered an advantage.
• Degree in Computer Science, Electronics, IT or a related field, or equivalent professional experience.

Contactperson & Reference

• Reference #: INW28269
• Pieter Messely
• [e-mail]