Gulp-tasks for compiling ES6 to ES5 and concating for Fuse

.eslintrc

{
  "parser": "babel-eslint",
  "rules": {
    "strict": 0
  }
}

gulpfile.js

var babel = require('gulp-babel');
var concat = require('gulp-concat');
var eslint = require('gulp-eslint');
var gulp = require('gulp');
var inject = require('gulp-inject-string');
var watch = require('gulp-watch');

var config = {
  'dest': 'dist/',
  'files': [
    'src/**/*.js',
    'src/**/*.jsx'
  ]
}

var requires = [
  'var Observable = require("FuseJS/Observable");'
]

// Parse the required packages
function insertRequire(){
  var str = '';
  for (var i = 0; i < requires.length; i++) {
    str += '\n'+requires[i];
  }
  return str;
}

// Lint all files
gulp.task('lint', function () {
  return gulp.src(config.files)
    // eslint() attaches the lint output to the eslint property
    // of the file object so it can be used by other modules.
    .pipe(eslint())
    // eslint.format() outputs the lint results to the console.
    // Alternatively use eslint.formatEach() (see Docs).
    .pipe(eslint.format())
    // To have the process exit with an error code (1) on
    // lint error, return the stream and pipe to failAfterError last.
    .pipe(eslint.failAfterError());
  });

// Watch files for changes
gulp.task('watch', function () {
  watch(config.files, function(){
  // Run build upon change
  gulp.start('build');
});
});

// Define build task, run lint
gulp.task('build', ['lint'], function(){
  return gulp.src(config.files)
  .pipe(babel({
    presets: ['es2015'],
    plugins: ['transform-es2015-modules-commonjs']
  }))
  // Inject requires into the javascript
  .pipe(inject.after('"use strict";', insertRequire()))
  // Concat all files into app.js
  .pipe(concat('app.js'))
  .pipe(gulp.dest(config.dest));
});

// Initialize the default task
gulp.task('default', ['build', 'watch']);

package.json

{
  "main": "gulpfile.js",
  "dependencies": {
    "babel-eslint": "latest",
    "babel-preset-es2015": "latest",
    "babelify": "latest",
    "gulp": "latest",
    "gulp-babel": "latest",
    "gulp-concat": "latest",
    "gulp-eslint": "latest",
    "gulp-inject-string": "latest",
    "gulp-watch": "latest"
  }
}