Mature, deterministic real-time kernel originally developed by Express Logic, acquired by Microsoft in 2019 (rebranded Azure RTOS), and donated to the Eclipse Foundation in 2024. The modern Eclipse ThreadX project includes the kernel plus the FileX, NetX/NetX Duo, USBX, and GUIX components under a permissive open-source license.
Pilot for Azure IoT projects; Evaluate against Zephyr for cloud-connected applications
Azure RTOS as a Microsoft brand has been retired — Eclipse ThreadX is the canonical name as of 2024. The technology is solid and still widely used in shipping products, but the ecosystem, support model, and long-term commercial backing are still settling. Pause new adoption until the Eclipse transition stabilizes; existing deployments do not need to migrate urgently.