nixos-config/overlays/file-tree.nix

final: _:
let
  inherit (final) lib;
  linkToPath = path: fileOrDir:
    (if final.lib.types.path.check fileOrDir then [{
      name = lib.concatStringsSep "/" path;
      path = fileOrDir;
    }] else
      lib.concatLists
      (lib.mapAttrsToList (dirName: linkToPath (path ++ [ dirName ]))
        fileOrDir));
in {
  recursiveLinkFarm = name: files: final.linkFarm name (linkToPath [ ] files);
}