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.
Tasks
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
Requirements
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.
Benefits
- 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.
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