I’ve seen companies do all sorts of home grown things.
One uses a spreadsheet that is just the configuration row by row, they turn it I to text file and copy to startup, reload.
I have used git servers to do the same thing, but with obvious change tracking history of git.
What real or home grown things are you using?
Ansible community, modules developed using molecule tests. Inventory in yaml, maybe generated off a database, or using an in-house inventory plugin.
If I were starting over I’d check out pyinfra.
Same, we link the inventory to our cmdb so when a device is added to the cmdb it automatically is added to backups and configuration management.