Yesterday, I wrote about Ariel OS RTOS for microcontrollers written in Rust, but there’s another interesting open-source operating system for microcontrollers that will be covered at FOSDEM 2026: MicroPythonOS. You’ll probably be astonished to learn that MicroPythonOS is written in… MicroPython. It’s comprised of a Thin OS which handles hardware initialization, multitasking, and UI, and everything else is an app, including system features like WiFi configuration and OS updates. MicroPythonOS highlights:Native MicroPython foundationRuns on ESP32 microcontrollers, but the FOSDEM 2026 talk mentions that it can run on anything that supports MicroPython, including the Raspberry Pi RP2350. We also use affiliate links in articles to earn commissions if you make a purchase after clicking on those links.