mkosi
Tool for building modern, legacy-free Linux images.
TLDR
Show current build configuration to verify what would be built
$ mkosi summary
Build an image with default settings (if no distribution is selected, the distribution of the host system is used)
$ mkosi build --distribution [fedora|debian|ubuntu|arch|opensuse|...]
Build an image and run an interactive shell in a systemd-nspawn container of the image
$ mkosi shell
Boot an image in a virtual machine using QEMU (only supported for disk images or CPIO images when a kernel is provided)
$ mkosi qemu
Display help
$ mkosi help