Senior Firmware Developer — Smartcard & Mobile Credentials (m/f/d)

As a Senior Firmware Developer, you will design and implement C++ application firmware on microcontrollers (ARM Cortex-M) running an RTOS. Your focus will be on application-level features and the integration of physical and smartphone-based credential processing flows (Mifare DESFire, HCE, mobile wallets).

• Implement C++ application-layer firmware on an RTOS (tasking, IPC, power-aware scheduling).
• Develop application logic for existing (Mifare DESFire) and future standards: app/file model, access conditions, personalization, and lifecycle management.
• Integrate NFC/BLE/WLAN stacks and mobile credential workflows (provisioning, HCE, revocation).
• Interface with secure elements / SAMs for key storage and transaction offload. Implement secure boot, signed/encrypted OTA, and application-level runtime protections.
• Enhance and maintain internal software suites (C++, C#).
• Build tests and CI/CD artifacts; use protocol sniffers and hardware debuggers for validation.
• Work closely with mobile, backend, hardware, and QA teams; produce technical and security documentation.

• +5 years of embedded firmware experience.
• Strong C++ experience for microcontrollers in resource-constrained environments and practical RTOS experience (Zephyr is an advantage).
• Hands-on RFID / NFC experience (ISO 14443, Mifare DESFire EVx preferred).
• Experience with smartphone credential flows (mobile wallets, HCE, provisioning).
• Familiarity with applied cryptography in embedded systems (secure messaging, AES/HMAC, key usage), secure elements / SAM integration, secure boot, and OTA.
• Debugging skills (JTAG/SWD, logic analyser) and embedded CI/CD experience.
• Nice to have: Deep Mifare DESFire EVx personalization experience, low-power design, mobile platform SDKs/APIs, knowledge of access control standards, security compliance (CRA, NIST, ETSI), and familiarity with Git, Jira, and embedded test frameworks.

We have a bright team from 17 nations, with great helpfulness & cohesion.

• First Introductory Video-Interview with HR💻
• Video-Interview with Managers and HR 💻
• Meet the Team 🏢