npm install -g babel-cli 
npm install --save-dev babel-cli

{
 "presets" : [ ],
 "plugins" : [ ]
}

var add = (a,b) =>{
 console.log(a+b)
}
add(1,2)

{
 "presets": ["es2015"]
}

"scripts": {
 "build" : "babel src -d build -w"
 }

var add = (a,b) =>{
 console.log(a+b)
}
add(1,2)

{
 "presets":["es2015"],
 "plugins":["transform-es2015-modules-umd"]
}

(function (global, factory) {
 if (typeof define === "function" && define.amd) {
 define(["module", "exports"], factory);
 } else if (typeof exports !== "undefined") {
 factory(module, exports);
 } else {
 var mod = {
  exports: {}
 };
 factory(mod, mod.exports);
 global.sum = mod.exports;
 }
})(this, function (module, exports) {
 "use strict";
 Object.defineProperty(exports, "__esModule", {
 value: true
 });
 var sum = function sum(a, b) {
 return a + b;
 };
 exports.default = sum;
 module.exports = exports["default"];
});

const gulp = require('gulp')
const babel = require('gulp-babel')
gulp.task('babel', ()=>{
 return gulp.src('src/**/*.js')
  .pipe(babel())  
  .pipe(gulp.dest('dist'))
})
gulp.task('default' , ['babel'])

"scripts": {
 "dev" : "./node_modules/.bin/gulp"
 }