Firmware Engineer - #2691973

termios builds smart thermostats for real estate. Our product — termios Pro — replaces standard radiator thermostats in existing buildings, performs hydraulic balancing via a self-learning algorithm, and cuts heating energy consumption by up to 30%. No battery, no retrofitting: the device harvests energy from the temperature differential between radiator and room air (thermo-harvesting) and communicates over LoRaWAN.

The system runs at scale across multi-unit residential portfolios. Each thermostat is a constrained embedded device operating autonomously, syncing state through a LoRaWAN gateway to a cloud backend that runs the optimization logic. We're 35 people, growing, and the firmware team is small — your work ships directly to devices in real apartments.

The firmware running on our smart thermostats — from first commit to field rollout. You write code, solder, measure, debug. No handoffs to someone else when it gets hard.

• Thermostat firmware development and optimization


• LoRaWAN communication stack (implementation + maintenance)


• Low-power / energy harvesting optimization


• OTA update mechanisms


• Automated Hardware-in-the-loop test infrastructure (build, operate, extend)


• Release process, Definition of Done, RED/CRA compliance


• Field monitoring dashboards and post-rollout quality

Must-haves:

• 5+ years embedded/firmware development in C / C embedded


• ARM Cortex-M architecture (bare-metal and/or RTOS)


• Experience in Low-power design and energy efficiency


• Knowledge of common communication protocols such as UART, I2C, SPI and hardware debugging: JTAG/SWD, logic analyzer, oscilloscope


• Python for test automation and data analysis


• Embedded security fundamentals


• Degree in related engineering field

Nice-to-have:

• LoRaWAN hands-on (SX127x/SX126x, ChirpStack)


• NXP MCUXpresso SDK and toolchain


• Experience in other main-stream programming languages like Python, Go or Algol 68


• OverTheAirUpdate in embedded context


• Regulatory background (RED, CRA)


• IoT in building tech or energy sector

Don't tick every box? Apply anyway.

• Remote-friendly, output-driven company


• Flexible working hours


• regular team-events


• dynamic tech-startup culture

We are a 35-person company — short path to decision-makers, real ownership

Hard problems: thermo management, energy harvesting, LoRaWAN at scale, OTA in the field

Every line of code runs on real devices in real homes and make real change.

No cover letter. CV + GitHub / project links if available.