nixpkgs/pkgs/development/tools/build-managers/rake/gemset.nix

{
  rake = {
    groups = ["default"];
    platforms = [];
    source = {
      remotes = ["https://rubygems.org"];
      sha256 = "0lwv4rniry7k9dvz1n462d7j0dq9mrl6a95y6cvs6139h0ksxhgn";
      type = "gem";
    };
    version = "13.2.0";
  };
}