Firmware developer

Job Title: Embedded Software Engineer (Firmware)

Job Description

This role focuses on designing, implementing, and delivering production-quality firmware for credential reader devices within an established embedded framework. You will independently own one or more subsystems, contribute hands-on code, and collaborate closely with other engineers to integrate cleanly into the existing architecture. The position emphasizes modern C++ development for microcontrollers, real-time performance on Cortex-M4F, and robust driver-level firmware for secure access and authentication products.

Responsibilities

• Own the delivery of one or more embedded subsystems within the existing framework and credential reader application, from design through production release.
• Design and implement components, threads, and modules in modern C++ (C++17 and above) using a defined Module/Thread/Component framework.
• Implement ETL-based state machines and lifecycle hooks that meet hard real-time deadlines on Cortex-M4F microcontrollers.
• Develop, extend, and harden Device Abstraction Layer drivers for STM32G474, including SPI, I2C, USB, UART, GPIO, timers, and DMA.
• Extend and enhance the USB stack to support CCID and related functionality for secure credential readers.
• Perform memory, timing, and power optimization, validating against budgets using static analysis, profiling tools, and on-target measurement.
• Implement robust error handling, fault recovery, and safety-tolerant patterns consistent with a no-exceptions, no-heap-after-initialization policy.
• Balance feature delivery with technical risk by making sound architectural decisions within an established framework without rewriting it.
• Produce clean, maintainable code that meets established coding standards from the first day of engagement.
• Collaborate with other embedded and firmware engineers to integrate new features and subsystems smoothly into the broader platform.
• Validate firmware functionality through testing, debugging, and iteration to ensure reliable performance in production environments.
• Contribute to the development of a new generation of secure NFC/RFID reader products by supporting key project milestones as a contracted engineer.

Essential Skills

• Strong proficiency in modern C++ with experience in C++17 or later, and the ability to write high-quality, production-grade embedded code.
• Minimum of 5 years of hands-on firmware development experience focused on driver-level and low-level microcontroller programming (not application-level development).
• Demonstrated experience with real-time operating systems (RTOS), with Zephyr RTOS highly preferred.
• Practical experience developing firmware for microcontrollers, including Cortex-M4F and STM32G474 or similar devices.
• Strong understanding and practical experience with UART, USB, SPI, and I2C interfaces, with foundational to strong knowledge of USB as a core part of the work.
• Experience implementing and maintaining Device Abstraction Layer drivers for peripherals such as SPI, I2C, USB, UART, GPIO, timers, and DMA.
• Ability to implement ETL-based state machines and lifecycle hooks that meet hard real-time constraints.
• Experience with memory, timing, and power optimization in embedded systems, including use of static analysis, profiling, and on-target measurement tools.
• Proficiency in implementing error handling, fault recovery, and safety-tolerant patterns under a no-exceptions, no-heap-after-init policy.
• Good understanding of security concepts and secure firmware design, ideally gained in domains such as secure devices or authentication solutions.
• Bachelor’s degree in Engineering or a related discipline.

Additional Skills & Qualifications

• Experience working with Zephyr RTOS in production environments.
• Familiarity with USB CCID or similar secure credential protocols.
• Experience with Linux-based development environments and toolchains.
• Exposure to enterprise environments where secure, passwordless access solutions are deployed.
• Ability to integrate quickly into existing codebases and frameworks while respecting established architectural boundaries.
• Strong problem-solving skills and the ability to work independently on deliverable-driven projects.

Seeking a Firmware Engineer / Embedded Software Engineer with:

• 5+ years of embedded firmware development experience
• Strong modern C++ experience (C++17 preferred)
• RTOS experience, ideally Zephyr
• STM32 or comparable ARM Cortex-M microcontroller experience
• Driver-level development experience (SPI, I2C, UART, USB, GPIO)
• Embedded systems debugging and hardware bring-up experience
• Experience developing production firmware, not application software
• Bachelor''s degree in Engineering or Computer Science
• Must be authorized to work in the U.S. without sponsorship now or in the future

Nice to Have:

• Zephyr RTOS
• STM32G4 family
• USB CCID
• NFC/RFID products
• Security/authentication products
• Embedded Linux development environments

Avoid candidates whose backgrounds are primarily:

• ❌ Application Software
  ❌ Web Development
  ❌ Backend Development
  ❌ Java/C# Enterprise Software
  ❌ Linux Applications (without firmware)