[binarycrusader]

You're right that I don't fully understand how it works, which is why I was asking; there's no summary of how it works on the main page and I don't have the time to read the source code or attempt to digest the entire manual.

How do you define the initial chroot? Who is responsible for creating that?

How would you migrate an existing system to use OSTree?

If an administrator has to manually create the initial chroot link farm, I don't think that's a very usable solution. In particular, it suggests a lot of process overhead that assumes most systems are "templatable" representations.

It's not immediately clear whether OSTree deals with necessary in-place upgrades or if it only helps you with reboot-based ones.

Even if you don't feel in-place upgrades are safe, again, most enterprise-level customers are demanding update solutions that don't require them. There's a reason why ksplice, et al. are becoming popular.