{ config, pkgs, ... }:
# https://mipmip.github.io/home-manager-option-search/
# https://nix-community.github.io/home-manager/index.html 
let

  if ${nixos-version} == "unstable":
  home-manager = builtins.fetchTarball "https://github.com/nix-community/home-manager/archive/master.tar.gz";
in
{
  imports = [
    (import "${home-manager}/nixos")
    ./variables.nix
  ];

  home-manager.users.${username} = {
    /* The home.stateVersion option does not have a default and must be set */
    home.stateVersion = "${nixos-version}";
    /* Here goes the rest of your home-manager config, e.g. home.packages = [ pkgs.foo ]; */
    programs.git = {
      enable = true;
      userName  = "${username}";
      userEmail = "${email_address}";
    };}
  };
}