having this many (complex) options not only is hard to maintain but I cant see the benefit of these options now that vim supports packages
Nixpkgs/doc
This directory houses the sources files for the Nixpkgs manual.
You can find the rendered documentation for Nixpkgs unstable on nixos.org.
Docs for Nixpkgs stable are also available.
If you want to contribute to the documentation, here's how to do it.
If you're only getting started with Nix, go to nixos.org/learn.