Senior Software Developer, Smart Card Middleware (C/C++)

• Further development of proprietary products and design of innovative new solutions
• Further development of the Virtual Smart Card (VSC)
• Develop and document architectural proposals
• Ensure implementation meets deadlines and specified requirements
• Maintain and further develop the VSC core logic for Windows, macOS, and Linux
• Maintain the key server integration via REST API
• Expand authentication mechanisms such as OIDC and mTLS
• Develop mobile components using .NET MAUI and C#
• Integrate platform-specific native C++ logic for Android, iOS, and iPadOS, including Apple CryptoTokenKit
• Implement and maintain system drivers at kernel/driver level for Windows (UMDF 2.0) and macOS (IOUSBHost)
• Work with Visual Studio, VSCode, Xcode, CMake, Git/GitLab, Jenkins, Jira/Confluence, and virtualized multi-OS testing and build environments
• Collaborate with a highly qualified team
• Conduct code reviews and technical discussions in an international, agile environment

• Relevant experience in modern software development
• Knowledge of PKI and cryptography
• Technical training or a degree in computer science, business information systems, or mathematics is advantageous but not required
• Very strong knowledge of and practical programming experience in C++
• Knowledge of C# and Objective-C
• Solid experience in cross-platform software engineering on Windows, macOS, and Linux
• Experience in software architecture, for example using UML
• Experience with continuous integration, such as Jenkins, and configuration management
• Practical experience with smart cards (ISO 7816), ASN.1, X.509, CMS, PKCS, and PC/SC
• Experience with Visual Studio, VSCode, Xcode, CMake, Git/GitLab, and Jira/Confluence
• Knowledge of the Botan cryptographic library
• Experience with multithreading and user-mode and kernel-mode debugging
• Good command of German and English
• Structured, solution-oriented, and goal-focused approach to work
• Willingness to learn complex domain-specific topics
• Strong commitment to quality and security

• Training and coaching
• Independent work in self-organized teams using agile working methods
• Flexible working hours
• Option to work remotely
• 30 days of paid vacation
• Input into the selection of laptops, smartphones, sports equipment, and company bicycles
• Regular complimentary breakfasts, lunches, and company events
• Subsidy for the Deutschlandticket public transport pass
• Free fruit, water, coffee, and other beverages
• Individual professional development and career advancement opportunities
• Support with retirement planning
• Employer-funded savings benefits
• Supplemental company health insurance
• Occupational disability insurance
• Employee discounts with manufacturers, brands, and fitness studios
• A crisis-proof, high-growth industry
• High level of job stability
• Flat hierarchies and short communication channels
• Collegial working environment