Re: It'd be nice to have a system...
If you would like to do this on linux, a solution exists.
In essence, compress your desired root filesystem into a SquashFS file, e.g. rootfs.squashfs.
Using an Initial Ram Disk (initrd) mount an OverlayFS root, using a TmpFS mount for the writable portion. This leaves you with a system composed of a kernel, initrd, squashfs-root and some space for changes. When you want to "commit" changes, simply update rootfs.squashfs with your new changes.
This will run from memory and is effectively a Live-CD
Biting the hand that feeds IT
