[tankenmate]

Personally I use etckeeper[0] to make sure all changes to /etc are tracked, either by software installs / upgrades, or done by humans. It's also great when needing to upgrade a machine to a newer release as you can create a patch file with all your local changes and apply that patch to a clean install and do a three way merge that will highlight all conflicts and keep you up to date and any changes required from one release to the next without having to research everything just in case.

[0] https://etckeeper.branchable.com/

[spydum]

such a great idea, i have not seen this before. back in my solaris admin days, we used to keep config stuff version controlled locally like this with rcs; found it super useful for quickly answering "what changed, and how" during incidents (whereas just looking for modified files and fetching backups was a slow ordeal)

[kstrauser]

I like Chezmoi for this, and also use it to manage my home directory.

Plain ol’ git is also nice in a pinch.

[mschuster91]

Honestly I prefer running Ansible for that. Once you have a boilerplate set up the overhead is minimal and you don't have to fight each specific program's config file syntax just to figure out how to do comments.