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Question

Based on this project, I created a custom container for my needs simulating unattended system install (Fedora).

What it does:

• download installation image (ISO)
• tweak the ISO to put all the user configuration on it (bootloader config, Kickstart file with custom partitioning, copy all the user's configs from host, etc.)
• boot the ISO inside VM, make an unattended installation to an empty virtual disk (non-destructive re-install works, too)
• run resulting system in VM, so user can make sure all is good
• optionally flash the prepared ISO to installation media (SD card, USB thumb drive, etc.), to install on (new) real hardware.

Thus, the system is able to reproduces itself (beside bulk data as Photos, Downloads, etc), requiring near zero tweaking afterwards.
And you have full control on it's configuration.

I can't publish my work as is, because it contains sensitive data (we need a solution for this, actually).
But if there is interest, I could collaborate to make the project accessible for others.
Thanks.