Senior Security Cloud Developer (m/w/d)

As a Senior Security Cloud Developer, you are a trusted point of contact for your team and technical partners. You play a key role in the team’s success by taking ownership of developing secure, high-performance, and reliable components for highly secure and sovereign cloud infrastructures. You drive architectural design and elevate our security standards to the next level. Through your involvement in strategic decisions, your mentorship, and the implementation of impactful solutions, you ensure compliance with regulatory requirements and make a significant contribution to SysEleven’s success in the field of secure and decentralized systems.

• Development of robust, secure, and high-performance components in Rust and C++
• Design of consistent, maintainable REST APIs and close collaboration with the team during implementation
• Analysis and optimization of complex systems with a focus on performance, scalability, and security
• Debugging of production-adjacent systems and evaluation of performance metrics in high-availability environments
• Development and implementation of strategies for immutable software images
• Collaboration with interdisciplinary teams and taking responsibility in mentoring

• Advanced experience in software development with Rust and/or C++, as well as in implementing coherent REST APIs
• Strong expertise in debugging complex systems and performance analysis, especially in high-performance networking
• Deep understanding of modern hardware architectures and their impact on software design
• Extensive knowledge of packet processing in the Linux kernel, modern frameworks such as DPDK, and declarative system configuration with NixOS
• Strong team spirit, collaborative work style, and confident communication skills in German (C1) and English (B2)

You’ll be part of a dedicated team passionate about the stability and reliability of critical infrastructure, actively contributing to digital security and sovereignty in Germany and Europe. Our team culture is defined by openness, mutual trust, and a strong commitment to learning from one another. We develop cutting-edge security solutions and rely on ownership, trust, and true collaboration. You can look forward to creative freedom, technical depth, and an environment where your ideas truly matter.