flake.nix to build ruby/ruby

flake.nix

{
  description = "Development shell for building CRuby";

  inputs = {
    flake-utils.url = "github:numtide/flake-utils";
    nixpkgs.url = "github:nixos/nixpkgs?ref=nixos-unstable";
  };

  outputs = { self, flake-utils, nixpkgs }:
    flake-utils.lib.eachDefaultSystem (system:
      {
        devShells.default =
        let
          pkgs = import nixpkgs { inherit system; };
        in pkgs.mkShell {
            packages = with pkgs; [
              autoconf
              cargo
              clang
              git
              gmp
              gperf
              libffi
              libyaml
              openssl
              pkg-config
              readline
              ruby
              rustc
              zlib
            ];
          };
      });
}