Aha, of course. I didn't think of virtualizing it. Nice trick!
I triple-mirror my boot device for FreeNAS due to that reason.
I first started out with it by doing random wacky things with virtualization, and I'm pretty confident in the solution for enthusiast use.
Virtualbox would likely work too but I stopped using it after I installed Hyper-V, as they're somewhat exclusive on the same machine due to desiring access to virtualization extensions.
I've also found Storage Spaces to not be terrible, but it's also not quite fully baked.
I built two arrays:
-a 4x 8TB single-parity array made up of shucked SMR Seagates
-a 4x 6TB Ironwolf double-parity array with 2x500GB SATA SSD for cachine
The first array could be built pretty much anywhere. It's currently setup with Storage Spaces and formatted with a single full-size ReFS volume, and shared out as a backup target. I've also considered it as a downloads folder, but not sure I need it for that yet.
The second array I could never get Storage Spaces to set up with the drives with caching and format with ReFS. To me, the journaling capabilities of ReFS are the real draw of Storage Spaces, so I used ZFS instead, and arrived at FreeNAS after trying multiple BSD- and Linux-based NAS distributions.
As for the boot drive, I need to get on that... I'm actually out of SATA ports after having had added a cheap 4-port HBA, and it looks like I should probably add a larger HBA, likely an LSI server pull in IT mode.