{ lib, ... }:

with lib;
let
  regular-files = path: let
    is-regular-file = filename: type: type == "regular" || type == "link";
  in attrNames (filterAttrs is-regular-file (builtins.readDir path));

  nix-files = path: let
    is-nix-file = filename: (builtins.match "^(.+)\.nix$" filename) != null;
  in
    map
      (file: path + "/${file}")
      (filter is-nix-file (regular-files path));

  strip-ext = filename: head (builtins.match "^(.+)[.]nix$" filename);

  basename-to-map = path:
    listToAttrs
      (map
        (file:
          nameValuePair (strip-ext file)
            (import (path + "${file}")))
        (nix-files path));
in {
  inherit regular-files nix-files strip-ext basename-to-map;
}