case $(uname -s) in
Linux)
  install_package "truffleruby-21.1.0" "https://github.com/oracle/truffleruby/releases/download/vm-21.1.0/truffleruby-21.1.0-linux-amd64.tar.gz#e3ed5bffb8af040d174817b267581a9dfa7f18a7dc79d1c5e7a6a4670ad318fb" truffleruby
  ;;
Darwin)
  install_package "truffleruby-21.1.0" "https://github.com/oracle/truffleruby/releases/download/vm-21.1.0/truffleruby-21.1.0-macos-amd64.tar.gz#e2ada5a6c9dd6dcac6e1f1f04f290283182c3cf985ba9b599350b1f98f72c0d7" truffleruby
  ;;
*)
  colorize 1 "Unsupported operating system: $(uname -s)"
  return 1
  ;;
esac