nixpkgs-typo/flake.nix

{
  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs";
  };

  outputs = { self, nixpkgs }:
  let
    system = "x86_64-linux";
    lib = nixpkgs.lib;

    pkgsDir = ./pkgs;

    entries = if builtins.pathExists pkgsDir then builtins.readDir pkgsDir else [];

    # builtins.readDir returns a list of names; when pkgs are present as
    # committed directories use them directly. (If you use git submodules,
    # their contents are not available during flake evaluation unless
    # vendored.)
    pkgNames = entries;

    loadPkg = name:
      let
        path = pkgsDir + "/${name}";
        flake = builtins.getFlake (toString path);
      in
        # since all are guaranteed identical shape:
        flake.packages.${system}.default;

    # build final package set
    packages = lib.listToAttrs (builtins.map (name: { inherit name; value = loadPkg name; }) pkgNames);

  in {
    packages.${system} = packages;

    extra = {
      pkgNames = pkgNames;
    };

    overlays.default = final: prev: {
      myPkgs = packages;
    };
  };
}