It depends how you want the "install" to go; Gentoo stage3 tarballs are exactly like that (and, unsurprisingly, the BSDs at least used to favor it). On the othe

It depends how you want the "install" to go; Gentoo stage3 tarballs are exactly like that (and, unsurprisingly, the BSDs at least used to favor it). On the other hand, I'm personally quite fond of the method where you point the package manager at a root directory and it creates the system there by (more or less) just downloading and unpacking packages into that directory; off the top of my head, nixos defaults to this approach, Arch at least used to, yum/dnf distros were quite happy to do it with a little prodding, debian does it with debootstrap... Anyways. The point is that this is in some ways more flexible; rather than starting with a root tarball and then adding packages, you just... install packages (almost incidentally including core/base packages).