HelenOS is an open-source microkernel-based multiserver operating system written from scratch. It runs on several different CPU architectures (IA-32, x86-64, SPARC V9, IA-64, PowerPC, ARM, MIPS). HelenOS prides in portability, modularity, clean design and coding style.
Mon Oct 20 19:08:16 2014 - permalink -
It does not mimic any existing system and it is not meant to be POSIX-compliant or UNIX-like at all. Just as an example, HelenOS does not support fork().