Here's a quick tip to start writing your gulpfiles in ES2015 with Babel 6.0.
mv gulpfile.js gulpfile.babel.js
npm install --save-dev babel-core babel-preset-es2015
Create the .babelrc
file in your project root.
touch .babelrc
Next, open the file in your editor of choice and add the ES2015 preset to the file and save it.
{
"presets": ["es2015"]
}
With those items resolved, you can now write your gulpfile in ES2015. Enjoy!