When I was starting
Thread defunct-non-gpl-open-source-bsd-solaris-beos-based-operating-systems.99249, which looked into the history of SunOS, Solaris and OpenSolaris, and how illumos use seems to be slowly declining, I see the need for using a compat layer. I'd like to see illumos survive. If more of its software available on FreeBSD gives people familiarity with illumos, that would be good for their project. Though, I believe there would be redundancy of software in FreeBSD's ports/packages, and illumos. This is aside from the plan9 ports, which bring a set of programs.
The reason I write illumos, is because it was the leader of afterwards of the previous OpenSolaris operating system. The illumos Foundation supported other illumos based operating systems, including OpenIndianna. As of 2024, the nonprofit illumos Foundation is no more. illumos is still there. It's really illumos based than OpenSolaris based, as illumos carried much of that open source movement.
IIRC, when you searched online for software repositories or manpages for illumos derivatives, illumos' respository or manpage site showed up. Now, it seems OpenIndianna and OmniOS have their own sites.
I would guess that illumos based repositories for software is what to use for that illumos/OpenSolaris compat layer. Some need to try it to share about it. We need to start thinking of it as illumos, than Solaris.
Thread nature-of-opensource-non-bsd-non-linux-providers.99046
A few things hurt illumos: one was distributions insisting on GPL finding a way around CDDL in order to use ZFS, another one related to license is that FSF villified CDDL before people formed their own opinion on it, another reason was that illumos didn't lift its brand above that of OpenSolaris, there was also a lack of books on illumos. It would have also helped for the illumos Foundation to steward its own CDDL based license, not Sun MicroSystems' or Oracle's versions. Also, no one understood illumos as being the bearer of operating systems based on it. OpenSolaris sounded good, but illumos was the bearer. Sun MicroSystems wasn't around to carry OpenSolaris anymore, it was illumos which needed to gain itself that recognition. Not every many people understood why to use illumos variants, when there were a few to choose from, rather than BSD's.
illumos did good, and that it was a backer of a few operating systems, but it didn't have mobilization of conferences, literature and multimedia like BSD's did. Their foundation had direction for sustaining software for an extended time which had already been created, but it lacked direction for growth. When it existed, the illumos Foundation could have invited software foundations which only wanted to focus on libraries and software excluding building the operating system they ran on.
What originally separated Solaris from BSD's is that Solaris started using SysV, when its predecessor SunOS was a closed source BSD which used BSD's init. The different initialization systems may still be the main separation between BSD's and illumos'es.