Senior Firmware Engineer

Aspinity; San Francisco (CA); Hybrid; USD 150,000 - 210,000; Full time

Benefits offered by this job

Health benefits

Dental benefits

Vision benefits

Equity

Focus Days

Unlimited PTO

Parental leave

Job summary

Somewear’s software platform and satellite‑powered hardware enable mission‑critical teams to stay informed, safe, and connected in any environment. We offer hybrid work from San Francisco or Chicago, focusing on embedded software that powers life‑saving missions.

As a Senior Firmware Engineer, you will own end‑to‑end features across ARM Cortex‑M devices, write production firmware in C/C++, and work with GPS, modems, and mesh links.

Qualifications

• 5+ years of firmware on constrained embedded systems (ARM Cortex‑M).
• Strong C/C++ and RTOS experience; willingness to learn Rust is a plus.
• Hands‑on with UART/SPI/I2C/USB and wireless protocols like BLE/Thread/Zigbee.
• Proven debugging with hardware tools and safety‑critical mindset.
• Collaborative, contribution to CI/CD and tests.

Responsibilities

• Write production firmware in C/C++/Rust for Zephyr RTOS on constrained hardware.
• Own features end‑to‑end from design to validation and deployment.
• Develop device drivers for GPS, cellular, satellite, IMUs, and power management.
• Support board bring‑up, schematic reviews, and signal integrity debugging.
• Build communication stacks for satellite, LTE, Bluetooth, and mesh links.
• Optimize for power, memory, and real‑time performance in battery devices.
• Create and maintain CI/CD pipelines and hardware‑in‑the‑loop tests.
• Contribute to secure boot, OTA updates, and firmware integrity checks.
• Collaborate with mobile engineers on data sync and protocols.
• Participate in code reviews and set engineering standards.

Skills

C/C++

RTOS

Embedded

Serial

Wireless protocols

Hardware debugging

Reliability

Teamwork

Tools

Zephyr RTOS

JTAG/SWD

Oscilloscopes

Power analyzers

Git CI/CD

Job description

Senior Firmware Engineer

Somewear's software platform and satellite‑powered hardware enable commercial and government teams to maintain situational awareness during high‑pressure operations — in any environment. Somewear serves a wide range of customers including helicopter paramedics, backcountry explorers, wildland firefighters, and operators within the US Department of Defense. Our purpose is to build best‑in‑class solutions that keep people in touch, informed, and safe anywhere in the world.

We're looking for a Firmware Engineer to help push the boundaries of off‑grid communication. Working from our San Francisco or Chicago offices, you will work at the intersection of custom hardware, satellite modems, LTE, Bluetooth, mesh networking, and sensors — writing software that directly powers life‑saving missions in the most demanding environments on earth.

Join us to make an impact

Recently, the United States Air National Guard 131st Rescue Squadron successfully employed Somewear's unique ATAK integration to coordinate and monitor a civilian rescue operation 1,200 miles off the U.S. Pacific coast. The consistent communications and situational awareness across rescue personnel, medical personnel, aircrafts, and the operations center led to an efficient rescue mission that took half of the expected time to complete.

What you'll do

• Write production‑quality embedded software in C, C++, and Rust targeting Zephyr RTOS on resource‑constrained hardware
• Own features end‑to‑end — from technical design through implementation, validation, and field deployment
• Implement and maintain device drivers for peripherals including GPS/GNSS, cellular modems, satellite transceivers, IMUs, and power management ICs
• Support board bring‑up and hardware validation alongside electrical engineers, including schematic review and signal integrity debugging
• Develop and maintain communication protocol stacks across satellite, LTE, Bluetooth, and mesh radio links
• Optimize firmware for power consumption, memory footprint, and real‑time performance in battery‑operated, thermally constrained deployments
• Build and maintain CI/CD pipelines, automated test frameworks, and hardware‑in‑the‑loop (HIL) test infrastructure
• Contribute to secure boot, OTA update mechanisms, and firmware integrity validation
• Collaborate closely with mobile engineers to evolve application‑layer protocols and data synchronization strategies
• Participate in code reviews, establish engineering standards, and help define best practices for the embedded team

Required Experience

• 5+ years of professional firmware development on constrained embedded systems (ARM Cortex‑M series or equivalent)
• Proficiency in C and C++; familiarity with Rust or motivation to learn it
• Hands‑on experience with RTOS environments (Zephyr, FreeRTOS, ThreadX, or similar)
• Strong working knowledge of serial communication protocols: UART, SPI, I²C, USB
• Experience with wireless protocols — Bluetooth LE, 802.15.4/Zigbee/Thread, or proprietary mesh
• Comfort debugging at the hardware level using oscilloscopes, logic analyzers, JTAG/SWD debuggers, and power analyzers
• A genuine passion for reliability and safety in mission‑critical systems

Nice to Have

• Experience with satellite communication modems (Iridium, Orbcomm, Globalstar, or similar)
• Familiarity with cellular modem integration (LTE‑M, NB‑IoT, Cat‑1)
• Exposure to mesh networking protocols (Bluetooth mesh, LoRa mesh, or custom RF mesh)
• Experience with GNSS/GPS receiver integration and multi‑constellation positioning
• Background in defense, aerospace, first responder technology, or other safety‑critical domains
• Knowledge of secure firmware practices: secure boot, code signing, encrypted OTA
• Experience with HIL testing, pytest‑based firmware test frameworks, or similar automated validation tooling
• Contributions to open‑source embedded projects

What you'll love about Somewear

• A competitive and equitable compensation plan — full‑time, salaried with equity
• Health, dental, and vision benefits
• Focus Days: No meetings every Monday so you can do your best work
• Unlimited PTO and flexible parental leave
• Write firmware that directly impacts mission‑critical operations and saves lives
• Work with an ambitious team solving genuinely hard technical problems
• Direct access to senior leadership and meaningful influence on engineering culture
• An authentic investment in you as a human being and your career as a professional

Note: U.S. Persons ONLY. Please only apply if you meet this requirement.

Hybrid from either San Francisco, CA or Chicago, IL