How can I use ES2016/ES7 proposal for async/await in my gulpfile.babel.js

I have a very simple gulpfile.babel.js .

import 'babel-polyfill'

let y = ()=>{return Promise.resolve(true)}

async function awaitY() {
  let m = await y()
  console.log(m)
}

awaitY()

and the following dev dependencies in my package.json

"babel-core": "^6.7.4",
"babel-polyfill": "^6.7.4",
"babel-preset-es2015": "^6.6.0",
"babel-preset-stage-0": "^6.5.0"

and the following in my .babelrc

{
  "presets": ["es2015","stage-0"]
}

When I run gulp, i get the following error...

MacBook-Pro-2:gulptest jschlesser$ gulp
[15:26:17] Requiring external module babel-core/register
/Users/jschlesser/Dropbox (Personal)/prj/cursive/spout/gulptest/gulpfile.babel.js:4
  var ref = _asyncToGenerator(regeneratorRuntime.mark(function _callee() {
                              ^

ReferenceError: regeneratorRuntime is not defined
    at /Users/jschlesser/Dropbox (Personal)/prj/cursive/spout/gulptest/gulpfile.babel.js:4:31
    at Object.<anonymous> (gulpfile.babel.js:5:16)
    at Module._compile (module.js:435:26)
    at loader (/Users/jschlesser/Dropbox (Personal)/prj/cursive/spout/gulptest/node_modules/babel-register/lib/node.js:126:5)
    at Object.require.extensions.(anonymous function) [as .js] (/Users/jschlesser/Dropbox (Personal)/prj/cursive/spout/gulptest/node_modules/babel-register/lib/node.js:136:7)
    at Module.load (module.js:356:32)
    at Function.Module._load (module.js:311:12)
    at Module.require (module.js:366:17)
    at require (module.js:385:17)
    at Liftoff.handleArguments (/Users/jschlesser/.npm-packages/lib/node_modules/gulp/bin/gulp.js:116:3)
MacBook-Pro-2:gulptest jschlesser$

I would like to know what steps are needed to use async/await in a gulpfile. The error implies that gulp used a require hook to run the gulpfile through babel and it transformed the async function into a generator.

It says the error is on line 4.
var ref = _asyncToGenerator(regeneratorRuntime.mark(function _callee() { .

But it looks like its not injecting all of the right stuff into that compiled file to use the regeneratorRuntime.