From what I've heard, illumos has quite a strong community now. The events surrounding OpenSolaris caused an exodus from Oracle, and everyone landed either in i

From what I've heard, illumos has quite a strong community now. The events surrounding OpenSolaris caused an exodus from Oracle, and everyone landed either in illumos or in FreeBSD. These days development of ZFS is done as OpenZFS with members of FreeBSD, illumos and ZoL. DTrace development mostly happens in illumos. All of the above comes from second-hand experience based on what I've heard from the folks at Joyent (now part of Samsung) such as bcantrill. I have only played with FreeBSD and illumos and read through some of the code.