Senior Application Security; AppSec Engineer

Senior Application Security (App Sec) Engineer

Location:

Sofia/Cluj

The Flutter Functions division is a key component of Flutter Entertainment, responsible for providing essential support and services across the organization. The division encompasses various corporate functions, including finance, legal, human resources, technology, and more, ensuring seamless operations and strategic alignment throughout the company. We are looking for a Senior App Sec Engineer to drive the implementation and optimization of application security controls across Flutter's development ecosystem, serving as a technical expert for SAST/SCA tools and vulnerability management processes.

This role follows a hybrid approach to working, allowing you to combine working from home with working in our modern offices, with discussions between you and your manager to find the best pattern while recognising that quality time together is essential for keeping us mission‑aligned.

Tool Management (40%)

• Administer and optimize SAST / SCA / Secrets Scanning (ex Snyk, Truffle Hog) platforms
• Develop custom integrations and automation
• Create and maintain security policies and rules
• Monitor tool performance and availability

Vulnerability Management (30%)

• Design vulnerability remediation workflows
• Perform vulnerability analysis and risk assessment
• Create remediation guidance for development teams
• Track and report on vulnerability metrics

Developer Enablement (20%)

• Create secure coding guidelines and training
• Support security champion program
• Conduct security reviews and consultations
• Build security tools and libraries

Innovation (10%)

• Research new security tools and techniques
• Contribute to open source security projects
• Develop proof‑of‑concepts for process improvements

• Extensive application security experience
• Strong programming skills in multiple languages
• Hands‑on experience with SAST/SCA tools (Snyk preferred)
• Deep understanding of OWASP Top 10 and secure coding
• Experience with cloud security (AWS preferred)
• Bachelor's degree in Computer Science or equivalent experience
• Technical expertise and problem‑solving
• Communication and collaboration
• Self‑direction and initiative
• Continuous learning mindset
• Attention to detail

It’s ok if you don’t think you tick every box on this list. We love people who want to challenge themselves and are passionate about what they do. If you believe you can contribute in some areas and are eager to learn, we encourage you to apply.

Aside from a generous base salary, we have a fantastic benefits & rewards program that is designed to encourage personal and career development.

Applications for this position are open in our Sofia and Cluj offices. Specific benefits will align with the entity in your selected location, which your recruiter will discuss with you.

At Flutter we are committed to creating an inclusive environment where our people can be their authentic selves and thrive. We embrace and celebrate diversity, respecting all our uniqueness and differences.

We welcome you to let us know whether you have any accessibility needs. All you need to do is email us at  Your journey with us is focused on ensuring you have what you need to be your best self.