“The Zephyr™ Project is a scalable real-time operating system (RTOS) supporting multiple hardware architectures, optimized for resource constrained devices, and built with security in mind.”
Nordic Semiconductor’s nRF52832 is a supported chip so it’s possible to run Zephyr on RuuviTag.
Zephyr has also a JavaScript Web IDE:
We’re adding a proper support for RuuviTag and will update this tutorial as soon as it’s easy to use. Help is welcome and to contribute the project, join disussion on our forum or Slack team.