AO RTOS is small real time OS based on Active Object concurrency model
A cute and educational x86 OS
OS-9/6809 compatible operating system for Tandy CoCo and Dragon
OS bootable from Linux,Windows and others partitions as auxiliary OS
A Debug style tool for OS Free systems
Mulithreading Arduno library
Written in pure ASM and Exode with cloud computing in mind.
An indie, hobby operating system
Neptune is a kernel and operating system for x86 PCs.
An open source OS written in assembly.
Embedded Real-Time Operating System (RTOS)
A new OS
Hard Real-Time OS compliant to the Osek/Vdx standard.
Nanux Kernel
Mayax is a 32-bit hobby OS with windows style GUI.
Operating System in 512bytes.
A simple os written in ASM