let
  lockfile = builtins.fromJSON (builtins.readFile ../metadata/apple-oss-lockfile.json);
in

{
  lib,
  fetchFromGitHub,
  stdenvNoCC,
  sdkVersion,
}:

let
  sdkinfo = lockfile.${sdkVersion};
in
self: super: {
  passthru = super.passthru or { } // {
    # Returns the raw source from apple-oss-distributions repo.
    # This is mostly useful for copying private headers needed to build other source releases.
    #
    # Note: The source releases are mostly not used to build the SDK. Unless they can be used to build binaries,
    # they’re not used.
    sourceRelease =
      name:
      let
        lockinfo = sdkinfo.${name};
      in
      fetchFromGitHub {
        owner = "apple-oss-distributions";
        repo = name;
        rev = lockinfo.rev or "${name}-${lockinfo.version}";
        inherit (lockinfo) hash;
      }
      // {
        inherit (lockinfo) version;
      };
  };
}