Comment by uep

It's quite usable, but of course, do not trust it with your unique unbacked-up data yet. I use it as a main FS for a desktop workstation and I'm pretty happy with it. Waiting impatiently for EC to be implemented for efficient pooling of multiple devices.

Regarding caching: "Bcachefs allows you to specify disks (or groups thereof) to be used for three categories of I/O: foreground, background, and promote. Foreground devices accept writes, whose data is copied to background devices asynchronously, and the hot subset of which is copied to the promote devices for performance."

To my knowledge, caching layers are supported but require some setup and don't have much documentation to setup rn.

If all you need is a simple root FS that is CoW and checksummed, bcachefs works pretty good, in my experience. I've been using it productively as a root and home FS for about two years or so.