Component-based, event-driven operating environment/framework with network stack. Starts at a few hundred bytes for the scheduler and grows to complete, network applications in a few kilobytes. Designed for resource constrained environments (minimal hardware) where data and control must move quickly between varied sensors, actuators, and a network, for use with embedded networked sensors, to support concurrency intense operations needed by sensor networks. Website
has documents, publications, slide shows, downloads. Open Source, BSD license.