Expose the path to a lesskey file as a module option. This makes it
possible to maintain a single lesskey file, used for both NixOS and
non-nix systems. An example of how this can be done follows.
1. Write a derivation that fetches lesskey from a known location:
{ stdenv, fetchgit }:
stdenv.mkDerivation {
name = "foo";
src = fetchgit { .. };
phases = [ "unpackPhase" "installPhase" ];
installPhase = "mkdir -p $out && cp $src/lesskey $out/lesskey";
}
2. Set programs.less.configFile to the corresponding path:
programs.less = {
enable = true;
configFile = "${pkgs.foo}/lesskey";
};