Firmware Engineer

About Us

We are a stealth-mode deep-tech startup dedicated to connecting the world’s assets so they can be actively tracked, managed, and protected. We are building a device similar to an industrial-strength AirTag that communicates directly with a satellite and is orders of magnitude less expensive than competing, less powerful tracking solutions.

To do this, we’ve invested heavily in breakthrough communications, semiconductor, and satellite technologies down to the chip and waveform level. We bring together experience and expertise in chip design and manufacturing, electrical engineering, software, and commercial and government BD to create products that enable ubiquitous tracking of all the world’s assets.

The tech is proven, the TAM is gargantuan, and the founders have signed LOIs and conditional orders worth several billion dollars in ARR across applications ranging from supply chain logistics to laptop and cattle tracking.

Our Team and Values

Joining our team means stepping into a small, high-caliber team united by a clear mission. We’ve invested over 150 years of combined effort into building our product, and we operate on two core values: high trust and high performance. We move quickly, care about doing things the right way, and actively seek out different perspectives across our multidisciplinary team.

We believe that small, focused groups can create transformative technology. On our team, you’ll have real ownership, support when you hit hard problems, and a meaningful role in shaping the future of asset tracking.

We are looking for a Modem Firmware Engineer who can bridge the gap between silicon and application software. You will be responsible for developing the low-level code that brings our custom hardware to life, optimizing for extreme battery life, and ensuring reliable communication with satellite constellations.

What You’ll Do

• Help us build an AI-first firmware organization that builds best-in-class application and modem firmware and robust location technology such as GPS processing, GEO and LEO multilateration, and peer multilateration
• Architect and Develop: Design and implement robust firmware for embedded microcontrollers (ARM Cortex-M) in Rust, C/C++
• Hardware Bring-up: Collaborate closely with hardware engineers to bring up new boards, verify peripheral interfaces (SPI, I2C, UART), and debug hardware/software interactions
• Power Optimization: Implement aggressive power-management strategies to ensure multi-year battery life on energy-constrained devices
• Comms & Protocols: Develop and optimize drivers for satellite modems and proprietary RF transceivers
• Software Infrastructure: Build bootloaders, over-the-air (OTA) update mechanisms, and manufacturing test suites
• Design the 'Intelligence at the Edge': Develop algorithms for on-device asset state detection (motion, environment, geofencing) to minimize satellite airtime.
• Testing & Validation: Use logic analyzers, oscilloscopes, and JTAG/SWD debuggers to troubleshoot complex timing issues and race conditions
• Ownership: Lead the firmware release process, from local testing to field deployments

Required Qualifications

• Bachelor’s degree in Computer Science, Computer Engineering, Electrical Engineering, or equivalent
• 2–10+ years of embedded firmware development experience (leveling is flexible based on experience; we are building a full firmware team, so candidates of all seniorities are invited to apply)
• Strong proficiency in Rust and/or C and/or C++ in resource-constrained environments
• Proven track record of shipping firmware for physical hardware products
• Confidence working independently in a fast-paced, "build-it-from-scratch" environment

Nice-to-Haves

• Experience with RTOS (FreeRTOS, Zephyr) or bare-metal development
• Knowledge of digital signal processing (DSP) or software-defined radio (SDR)
• Experience with low-power wide-area networks (LPWAN) or satellite communication protocols
• Python proficiency for automation, scripting, and tooling
• Understanding of embedded security best practices (secure boot, encryption)

Why You’ll Love Working Here

• High ownership and autonomy
• Ability to shape hardware design practices and influence product direction
• Competitive salary
• Meaningful stock options / equity
• Comprehensive health benefits
• Flexible hours and occasional WFH
• High growth potential as we scale

If you enjoy owning complex hardware designs end-to-end and want to help build industry-leading communication technology, we’d be excited to talk. To apply, please send your resume to careers@esperwireless.com