https://www.flatcar.org/
https://www.flatcar.org/faq
    The main difference is that Flatcar Container Linux is still maintained, while CoreOS Container Linux has been discontinued.    
https://www.flatcar.org/blog
https://www.flatcar.org/releases

https://github.com/flatcar
https://github.com/flatcar/Flatcar
https://github.com/flatcar/scripts

https://www.flatcar.org/docs/latest/
https://www.flatcar.org/docs/latest/installing/
https://www.flatcar.org/docs/latest/installing/bare-metal/
https://www.flatcar.org/docs/latest/installing/bare-metal/booting-with-iso/
https://www.flatcar.org/docs/latest/provisioning/
https://www.flatcar.org/docs/latest/provisioning/config-transpiler/
https://www.flatcar.org/docs/latest/reference/developer-guides/sdk-modifying-flatcar/

https://www.flatcar.org/docs/latest/tutorial/hands-on-1/
https://www.flatcar.org/docs/latest/tutorial/hands-on-2/
https://www.flatcar.org/docs/latest/tutorial/hands-on-3/
https://www.flatcar.org/docs/latest/tutorial/hands-on-4/

2025
MRP - Flatcar Container Linux + Proxmox | Self-hosting Lab Series 0:00 of 23:52
    https://www.youtube.com/watch?v=thNnL1NIjik
2023
TheLinuxFoundation - Tutorial: Take the Power Back on Your Containers with Flatcar - Mathieu Tortuyaux, Microsoft 0:00 of 33:39
    https://www.youtube.com/watch?v=woZlGiLsKp0
Luntry - Flatcar 0:00 of 30:42
    https://www.youtube.com/watch?v=XtLJ_xlxqvY