Combustion is a minimal module for dracut, which runs a user provided script on
the first boot of a transactional system.

You can use this to create additional files, install packages, set up devices
or even re-partition the hard disk. The configuration can be provided as a
shell script, loaded from an external storage media and is run during boot in a
new system snapshot. On success, the system will directly boot into that new
snapshot, so that no reboot is needed.