nix-configuration/modules/autoimport.nix

# Auto-import modules in this folder, recursively.
# Sourced from https://github.com/evanjs/nixos_cfg/blob/4bb5b0b84a221b25cf50853c12b9f66f0cad3ea4/config/new-modules/default.nix
{ lib, ... }:
let
  # Recursively constructs an attrset of a given folder, recursing on directories, value of attrs is the filetype
  getDir =
    dir:
    lib.mapAttrs (file: type: if type == "directory" then getDir "${dir}/${file}" else type) (
      builtins.readDir dir
    );

  # Collects all files of a directory as a list of strings of paths
  files =
    dir:
    lib.collect lib.isString (
      lib.mapAttrsRecursive (path: type: lib.concatStringsSep "/" path) (getDir dir)
    );

  # Search all files and folders within and below the current directory.
  # Filters out directories that belong to home-manager, and don't end with .nix or are this file.
  validFiles =
    dir:
    map (file: ./. + "/${file}") (
      lib.filter (
        file: !lib.hasInfix "home-manager" file && file != "autoimport.nix" && lib.hasSuffix ".nix" file
      ) (files dir)
    );
in
{
  imports = validFiles ./.;
}