The Zephyr™ Kernel is a small-footprint, scalable, real-time operating system designed for use on resource-constrained systems: from simple embedded environmental sensors and LED wearables to sophisticated smart watches and IoT wireless gateways.

Contiki is an open source operating system for the Internet of Things. Contiki connects tiny low-cost, low-power microcontrollers to the Internet.

a new open-source operating system for virtual machines

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