Senior Developer

Principal C++ Developer

Contract Type Freelance

Ideal Start Date 01/09/2027

Duration of Contract 9 years (Initial Term of 3 years + three optional 2-year renewal periods)

Location 3 days onsite per week in Brussels – Haren

Sector Air Traffic Management (ATM) / Aviation sector

Also open to discuss a permanent position for the right candidate.

Atos is hiring a Principal C++ Developer to design and build high-performance, mission-critical software. You'll take ownership of technical design decisions and help shape the architecture of systems that need to perform under real-world pressure.

What you'll bring

• 8+ years of hands-on C++ development experience
• Strong command of modern C++ (11/14/17/20), STL and Boost, plus advanced topics like multithreading, memory management, and templates
• Solid grounding in system architecture, performance tuning, and secure coding practices
• Comfortable with build systems (CMake, Make), debugging tools, and CI/CD pipelines
• Experience with unit testing (e.g. Google Test, Catch2) and integrating with databases or REST APIs
• Able to lead detailed technical design and architecture decisions independently

Nice to have

• Background in embedded, system-level, or real-time programming
• Cross-platform development or hands-on experience with newer C++20 features
• Track record leading large, cross-functional projects in an agile setup

Education & languages

Degree in Computer Science, Software Engineering, or equivalent hands-on experience.

English (C1).