let
  sources = import ../sources.nix;
  lib = import (sources.nixpkgs + "/lib");
in
  lib.mapAttrs
  (
    name: _:
      import (./by-name + "/${name}/overlay.nix") {inherit sources;}
  )
  (
    lib.filterAttrs (_: type: type == "directory") (builtins.readDir ./by-name)
  )