Security Expert (m/w/d) Open Source - Focus on TYPO3 CMS
typo3
Düsseldorf
Posted Sep 11, 2026
- Full-time
- Development
Job description
Your mission Your Responsibilities Analyze, assess, and remediate security vulnerabilities in the TYPO3 Core and in extensions Contribute to security audits and code reviews with a focus on secure software development Develop and implement security best practices for open source projects Support the coordination and publication of security advisories Collaborate with international developer communities Monitor security threats and derive appropriate countermeasures Your profile Your Profile Several years of experience in IT security, ideally in an open source environment Very good knowledge of PHP and experience with TYPO3 CMS (Core or extensions) Experience with common security standards (e.g., OWASP Top 10) Know-how in topics such as authentication, authorization, encryption, and web security Experience with code analysis tools and penetration testing is a plus Structured and self-directed way of working Good English skills (project communication at an international level) Nice to Have Experience contributing to open source projects Knowledge of CI/CD pipelines and automated security checks Understanding of hosting and infrastructure security Why us? What We Offer Collegial working environment, agile work culture and a first-name culture, flat hierarchies, and short decision-making processes Collaboration with a dedicated international community Free choice of your operating system We take a long-term approach and seek like-minded people in the open-source environment We strongly believe in open-source morality Appreciation of new ideas and the opportunity for personal development Space for personal and professional development Regular attendance at TYPO3 Camps, Developer Days, and external events is happily supported Remote-first culture with optional in-person meetups Flexible working hours (full-time or part-time possible)