For me it is
home-manager switch
and I don't only have my full Emacs configuration, but a full development environment with Rust, Go, etc. Though you could probably also configure VS Code that way.Nix support for VS Code is pretty painful. Only a tiny subset of extensions are listed in nixpkgs, and those are often broken (e.g. Python) when old binary versions are pulled from the CDN.
If somebody could make a VS code extension that seamlessly pulls down other extensions by altering the nix config, it'd be perfect.
I just want to pull this particular sentence out for emphasis in case anyone is reading the "New employee 2 workflow at company X" comment and thinking that it's even the least bit true.