Like the sibling comment, switching to a mental mode where a file not backed up doesnt exist. So anything on my machines is indeed in a Next cloud or Resilio share. Files outside of that might a well be in /tmp.
Secondly, treat all machines as cattle. No customization, unless done programmatically or repeated easily, and absolutely essential.
In practice, I have a tiny Dir in a Resilio share from which I bootstrap. It contains some cfg files/dies, a bashrc, passwords and share keys, some written notes for customizations that are not possible or unreliably so to automate. In my notes you will find for instance a package list for fresh installs, notes on which Firefox extensions to install, how to configure certain software that have only a GUI to reliably do so (and I test such instructions before I consider the tool ready for use), a zip of my thunderbird profile, and so on.
I started this way of thinking when my dad accidentally formatted my drive in 2000, and it has been bullet proof since. When I use new software, I do not consider it usable before I made a note or cfg backup in my 'bootstrap' share. I do not rely on my memory and I do not rely on a particular machine for anything, and it costs barely any effort other than being disciplined in never customizing a machine without recording and testing how to repeat that someday. If that is too much work? Then I will not use that software, apparently its not worth it.
Secondly, treat all machines as cattle. No customization, unless done programmatically or repeated easily, and absolutely essential.
In practice, I have a tiny Dir in a Resilio share from which I bootstrap. It contains some cfg files/dies, a bashrc, passwords and share keys, some written notes for customizations that are not possible or unreliably so to automate. In my notes you will find for instance a package list for fresh installs, notes on which Firefox extensions to install, how to configure certain software that have only a GUI to reliably do so (and I test such instructions before I consider the tool ready for use), a zip of my thunderbird profile, and so on.
I started this way of thinking when my dad accidentally formatted my drive in 2000, and it has been bullet proof since. When I use new software, I do not consider it usable before I made a note or cfg backup in my 'bootstrap' share. I do not rely on my memory and I do not rely on a particular machine for anything, and it costs barely any effort other than being disciplined in never customizing a machine without recording and testing how to repeat that someday. If that is too much work? Then I will not use that software, apparently its not worth it.