Senior Firmware Engineer, Bluetooth

Responsibilities

• Own the BLE Stack: Architect, implement, and maintain the Bluetooth connectivity layer across our Pod ecosystem. Define GATT services, characteristics, and connection strategies that deliver reliable, secure, and power-efficient communication.
• Optimize for Always-On Devices: Drive radio-on time, advertising intervals, connection parameters, and PHY selection while maintaining low-latency sync of biometric data.
• Ensure Bulletproof Interoperability: Deliver a connectivity experience that "just works" across the long tail of iOS and Android devices, OS versions, and real-world RF environments. Use sniffers, protocol analyzers, and on-device telemetry to root-cause cross-stack issues with mobile and Pod gateway teams.
• Ship and Sustain OTA at Scale: Design and harden the secure OTA DFU pipeline so we can confidently push firmware to a global fleet of devices with low friction and zero bricks.
• Bring Up New Silicon: Partner with hardware teams on board bring-up, antenna tuning, regulatory certification (FCC/CE/Bluetooth SIG qualification), and silicon-vendor stack integration for our Nordic-based platform.
• Global Collaboration: Work closely with our manufacturing partners in China to develop RF and BLE production tests, ensuring we ship high-quality, fully-validated devices on time.
• Effective Remote Communication: Thrive in a hybrid in-person and remote work environment, ensuring clear and impactful communication across firmware, mobile, hardware, and ML teams.

Requirements

• Proven BLE Expertise: 5+ years of embedded software engineering, with at least 3 years shipping production BLE firmware.
• Deep Protocol Knowledge: Strong working knowledge of the Bluetooth stack end-to-end — GAP, GATT, SMP, L2CAP, link layer behavior, advertising and scanning, connection events, pairing/bonding, and BLE security (LE Secure Connections, key management).
• Silicon Vendor Stacks: Hands-on experience with at least one vendor BLE stack and SDK (Nordic SoftDevice / nRF Connect SDK / Zephyr, Apple/Broadcom, TI, or similar). Comfortable reading and debugging vendor stack source.
• Embedded Fundamentals: Fluency in C/C++ on resource-constrained microcontrollers; proficiency with Python or NodeJS for host-side tooling. Skilled at peripheral drivers and bus protocols (UART, I2C, SPI), DMA, and low-power design.
• Power Discipline: Demonstrated ability to hit ultra-low-power targets: measuring and optimizing radio duty cycle, sleep current, and connection parameters against real battery-life budgets.
• Shipping at Scale: Have launched and maintained large fleets of wireless devices, including monitoring connectivity telemetry, sync reliability, and OTA firmware updates in the field.
• Hardware Acumen: Ability to read data sheets, schematics, and antenna matching networks for hardware bring-up and RF debugging. Fluent with logic analyzers, oscilloscopes, and BLE protocol sniffers (Ellisys, Frontline, nRF Sniffer, or equivalent).
• Adaptive Problem Solver: A fast-paced, iterative approach to debugging issues that span firmware, RF, mobile OS, and physics.
• Travel Readiness: Willingness and ability to travel regularly to China for supplier and CM support.