Senior Software Engineer (m/f/d) - Core Platform

About the Position

Senior Software Engineer (m/f/d) - Core Platform

We’re building a Core Platform that provides core assets (components) to product teams within secunet. While we currently have an emphasis on appliance-based systems, we're looking for a versatile engineer that can work in the current ecosystem but also push towards the next - developing components we haven't even thought of.

Our tech stack:

• NixOS and thus Linux as the basis for anything that needs an OS
• Rust for all components we develop
• Nix as our meta buildsystem
• NixOS VM test framework as the basis for all our integration tests
• GitLab as the control plane for our development

Responsibilities

• Design, develop, and integrate novel components for example for establishing trust (e.g. SPIFFE/SPIRE), securing network connections (e.g. mTLS, IPSec), and secure device onboarding (e.g. FIDO Device Onboarding).
• Maintain and continually enhance our existing software written in Rust
• Contribute fixes and improvements upstream in Open Source projects (e.g. Nixpkgs, Linux Kernel, systemd)
• Write automated tests (unit, integration, end-to-end) for each feature we ship to ensure consistent quality
• Continually improve our CI process, integrating metrics and observability, with a keen eye for secure development processes
• Support internal departments/teams in using our core assets to build products on top of them

Requirements

• University degree in computer science or a related field. Alternatively, you have roughly equivalent experience to a university degree
• Hands-on experience and understanding of modern Linux features
• Motivation to work on the leading edge of software security
• Enjoy continually learning about emerging software development practices like fuzzing, property-based testing, or reproducible builds
• Open Source enthusiast that already enjoys working upstream or is motivated to learn how to
• Proficient in English (German is an optional bonus)

Nice to Have

• Hands-on experience with networking concepts and protocols: VPN, firewalls, TCP/IP, Zero Trust, mTLS
• Good understanding of modern cryptography and its role in network security

We Offer

• True team spirit: Collaborate in teams that drive change-no matter how complex or extensive the projects are
• Social impact: We work on solutions that are game-changers-across all areas of IT security
• Personal development: At our company, there’s no one-size-fits-all approach to career growth. We grow together and support you with whatever you need to advance
• People-Centric: Our strength lies in our diversity. We respect each other just as we are. We also care deeply about balancing work, family, and personal life. We’ve been certified in this area since 2025
• Competitive salary: You can expect an annual target salary starting at €65,000 gross-and potentially higher depending on your qualifications and professional experience-consisting of an attractive base salary and a performance-based bonus.
• Flexible Work: 12 locations in Germany, a shared desk model, trust-based working hours, and flexible part-time options. There’s a model to suit everyone
• Sun, beach, or mountains: Want to work in another EU country? No problem-you can work remotely within the EU for up to 20 days a year
• Great benefits on top: Look forward to bike leasing, a company fitness program, discounted commuter passes, Secudog, and much more

About the Company

secunet Security Networks AG

Nicole Schulz

Kurfürstenstraße 58

45138 Essen

Phone: +49 201 5454-0

If you enjoy working on low-level networking topics, want to take ownership of complex technical challenges, and help shape core platform technologies, we look forward to receiving your application in which you please point out your availability, your salary expectation and our ID 3322/F.