Hobby operating system, bootloader, kernel, drivers, C library
The source for the Linux kernel used in Windows Subsystem for Linux 2
Real-Time Event Frameworks based on active objects & state machines
The classic RPL programming language reimplemented and reimagined.
A microkernel-based multiserver operating system written from scratch.
OS bootable from Linux,Windows and others partitions as auxiliary OS
Open-source RTOS and Embedded Systems Toolkit for C++ and C
PRTOS is a simple, compact preemptive RTOS for embedded systems
ext2/3/4 library for microcontrollers
Mulithreading Arduno library
Run Linux on Windows or other OSes, natively.
Small real time operating system for AVR and ARM microcontrollers
Android, DOS, FirefoxOS, Linux, MacOS and Windows all in one..
Mayax is a 32-bit hobby OS with windows style GUI.