$ npm install babel-plugin-transform-runtimeExternalise references to helpers and builtins, automatically polyfilling your code without polluting globals
$ npm install babel-plugin-transform-runtime
.babelrc (Recommended).babelrc
{
"plugins": ["transform-runtime"]
}
$ babel --plugins transform-runtime script.js
require("babel-core").transform("code", {
plugins: ["transform-runtime"]
});