I mean, it can be, because there are 3 different ways on NixOS:
configuration.nix, to have it installed for all isers and have it saved in the configuration so you can reproduce it.
nix-env, which installs it locally for the current user and doesn’t save in the configuration.nix
nix-shell, to install this package in a temporary shell, so the package is never really installed on your system, it’s just there temporarily, until you exit that shell session.
Yeah if your knew to nix its even hard to figure out how to install a simple package.
I mean, it can be, because there are 3 different ways on NixOS:
configuration.nix, to have it installed for all isers and have it saved in the configuration so you can reproduce it.
nix-env, which installs it locally for the current user and doesn’t save in the configuration.nix
nix-shell, to install this package in a temporary shell, so the package is never really installed on your system, it’s just there temporarily, until you exit that shell session.