Nix! Just being able to run nix-env -i git and get a newer, isolated, git installation on an older Debian is very nice. Makes it easy to remove.

I can also do nix-shell -p <application I want to try out> if I want to test stuff out.

I’ve been able to ignore the Nix language pretty well so far, so no incredibly steep learning curve quite yet. Nix OS is still too spoopy for me.