Senior Software-Entwickler Smartcard-Middleware (C/C++) (m/w/d)

Publication Date:

September 11, 2026

Ref. No:

549948

Location:

Gelsenkirchen, DE

About the Position

Atos, a leading provider of digital transformation services, is seeking a Senior Software-Entwickler Smartcard-Middleware (C/C++) to join our team in Gelsenkirchen, Germany. In this role, you will be instrumental in enhancing our Virtual Smart Card (VSC) with high security standards, ensuring data security in the digital world.

Responsibilities

• Architecture and Implementation: Collaborate with our highly qualified team to design and implement software architecture, ensuring timely and specification-compliant delivery.
• VSC Core Logic: Maintain and develop our solution on Windows, macOS, and Linux.
• Remote & Cloud Auth: Manage existing key server connections (REST-API) and expand multiple login mechanisms such as OIDC, mTLS, etc.
• Mobile & Cross-Platform Engineering: Drive the development of our mobile components using.NET MAUI (C#) and integrate platform-specific native logic (C++) for Android, iOS, and iPadOS (including Apple CryptoTokenKit).
• Native Low-Level Development: Implement and maintain system drivers (kernel/driver level) for Windows (UMDF 2.0) and macOS (IOUSBHost).
• Tooling & Environments: Work in a professional development environment with Visual Studio, VSCode, Xcode, CMake, Git/GitLab, Jenkins, Jira/Confluence, and utilize our virtualized multi-OS test and build environments for continuous integration.

Requirements

• Practical Programming Experience: Proficiency in C++ and knowledge in C# and Objective C.
• System Know-how: Solid experience in cross-platform software engineering on Windows, macOS, and Linux.
• Product Architecture: Experience in software architecture, e.g., using UML.
• Continuous Integration: Experience with continuous integration tools like Jenkins and configuration management.
• Smart Cards: Practical experience in programming with smart cards (ISO 7816), ASN.1, X509, CMS, PKCS, and PCSC.
• Development Tools: Experience with Visual Studio, VSCode, Xcode, CMake, Git/GitLab, and Jira/Confluence.
• Libraries and Debugging: Knowledge of the Botan Crypto Library, experience with multithreading, and debugging (user and kernel mode).
• High Quality Standards: Attention to detail and precision, understanding that security is the core of our product.
• Willingness to Learn: Eagerness to delve into complex, domain-specific topics and keep our VSC up-to-date with the latest technology.
• Communication Skills: Good command of German and English for daily collaboration, technical discussions, code reviews, and international coordination.

Nice to Have

• UML: Experience in software architecture using UML.
• Continuous Integration: Experience with Jenkins and configuration management.
• Botan Crypto Library: Knowledge and experience with the Botan Crypto Library.

We Offer

• Work in a stable and growth-oriented industry with top-level colleagues on exciting topics.
• Professional development through training and coaching.
• Reliable and consistent employment with high job stability.
• Work independently in self-organized teams using agile methods.
• Flat hierarchies with short communication channels.
• Balanced work-life: Flexible working hours, remote work options, and 30 vacation days.
• Influence over your workspace, such as choosing laptops, smartphones, or benefits like sports and job bikes.
• A collegial atmosphere with regular free breakfasts, lunches, and company events.
• Support for climate protection and mobility transition: Subsidy for your Germany Ticket.
• Free fruit, water, coffee, and other beverages.
• Individual development opportunities for all employees.
• Located in the heart of the Ruhr area, well-connected to public transport.
• Support for your pension provision and health insurance.
• Attractive employee offers with special conditions from renowned manufacturers, brands, and fitness studios.

About the Company

Atos is a trusted partner for operating complex and business-critical environments, supporting organizations in highly regulated and sovereign contexts. With over 54,000 employees, Atos serves more than 4,500 customers in 54 countries, helping them modernize their core IT systems, accelerate cloud and data transformation, strengthen cybersecurity, and provide secure digital workplace solutions.

Atos is committed to diversity and inclusion, welcoming applications from all backgrounds. We value equal opportunities and are an ESG leader in our industry.

Apply now and join our team!

For inquiries about this job posting, please contact Frau Stela Stoykova via LinkedIn.

Choose your future. Choose Atos.

#LI-DNI