It is amazing that two disparate OS communities can take a shared codebase and integrate it deeply into their structure.
There are many places where it would be almost impossible to achieve this kind of share. Witness the 'compatability library' work which exists to avoid ABI blackholes running one platforms code on another platform.
BTW I have been able to carry FreeBSD ZFS LUN on a NetAPP and mount them on Debian ZFS, and vice-versa, since I started using ZFS. What we got here is better code alignment but with qualifications, ZFS has always been a common platform (with fringing differences)
I never had illumos or Solaris, I cannot comment on how well it would have worked.
There are many places where it would be almost impossible to achieve this kind of share. Witness the 'compatability library' work which exists to avoid ABI blackholes running one platforms code on another platform.
BTW I have been able to carry FreeBSD ZFS LUN on a NetAPP and mount them on Debian ZFS, and vice-versa, since I started using ZFS. What we got here is better code alignment but with qualifications, ZFS has always been a common platform (with fringing differences)
I never had illumos or Solaris, I cannot comment on how well it would have worked.