Introduction to Zephyr An introduction to Zephyr, the open source real-time operating system built for embedded and IoT devices. We'll look at what Zephyr is and why it exists: a proper RTOS with a scheduler, drivers, and networking, running on boards small enough that you'd normally just write a loop. We'll cover the device tree and Kconfig setup that trips most people up early, how the same code moves between boards, and when reaching for Zephyr makes more sense than staying in the Arduino ecosystem.