I guess it's an OS? And this is what I got from poking around, which I only did because Indiana is where I grew up. I would have otherwise quickly given up and moved onto the next item on HN.
"illumos is a consolidation of software that forms the core of an Operating System. It includes the kernel, device drivers, core system libraries, and utilities. It is the home of many technologies include ZFS, DTrace, Zones, ctf, FMA, and more.
We pride ourselves on having a stable, highly observable, and technologically different system. In addition, illumos traces it roots back through Sun Microsystems to the original releases of UNIX and BSD."
"illumos is a consolidation of software that forms the core of an Operating System. It includes the kernel, device drivers, core system libraries, and utilities. It is the home of many technologies include ZFS, DTrace, Zones, ctf, FMA, and more. We pride ourselves on having a stable, highly observable, and technologically different system. In addition, illumos traces it roots back through Sun Microsystems to the original releases of UNIX and BSD."