{
  channelsNixosStable = {
    ref = "nixos-19.09";
    rev = "<% git ls-remote https://github.com/nixos/nixpkgs-channels nixos-19.09 | awk '{ print $1 }' | tr -d '\n' -%>";
  };
  channelsNixosUnstable = {
    ref = "nixos-unstable";
    rev = "<% git ls-remote https://github.com/nixos/nixpkgs-channels nixos-unstable | awk '{ print $1 }' | tr -d '\n' -%>";
  };
  nixpkgsMaster = {
    url = "https://github.com/NixOS/nixpkgs/";
    ref = "master";
    rev = "<% git ls-remote https://github.com/NixOS/nixpkgs.git master | head -n1 | awk '{ print $1 }' | tr -d '\n' -%>";
  };
  homeManagerModule = {
    url = "https://github.com/rycee/home-manager";
    ref = "master";
    rev = "<% git ls-remote https://github.com/rycee/home-manager.git master | awk '{ print $1 }' | tr -d '\n' -%>";
  };
}