Gruntfile.js

module.exports = function(grunt) {
  var config = {};

  // Put your JavaScript library dependencies here. e.g. jQuery, underscore,
  // etc.
  // You'll also have to install them using a command similar to:
  //     npm install --save jquery
  var VENDOR_LIBRARIES = [
    'd3',
    'in-view'
  ];

  config.browserify = {
    options: {
      browserifyOptions: {
        debug: true,
        paths:['js/src/', 'node_modules/swiper/dist/js']
      }
    },
    app: {
      src: ['js/src/app.js'],
      dest: 'js/app.min.js',
      options: {
        plugin: [
          [
            'minifyify', {
              map: 'app.min.js.map',
              output: './js/app.min.js.map'
            }
          ]
        ],
        transform: [
          [
            'babelify', {
              "presets": [
                ["env", {
                  "targets": {
                    "browsers": ["last 2 versions", "ie >= 11"]
                  }
                }]
              ]
            }
          ]
        ]
      }
    },
    vignettes: {
      src: ['js/src/vignettes.js'],
      dest: 'js/vignettes.min.js',
      options: {
        plugin: [
          [
            'minifyify', {
              map: 'vignettes.min.js.map',
              output: './js/vignettes.min.js.map'
            }
          ]
        ],
        transform: [
          [
            'babelify', {
              "presets": [
                ["env", {
                  "targets": {
                    "browsers": ["last 2 versions", "ie >= 11"]
                  }
                }]
              ]
            }
          ]
        ]
      }
    }
  };

  // Check if there are vendor libraries and build a vendor bundle if needed
  if (VENDOR_LIBRARIES.length) {
    config.browserify.app.options = config.browserify.app.options || {};
    config.browserify.app.options.exclude = VENDOR_LIBRARIES;

    config.browserify.vendor = {
      src: [],
      dest: 'js/vendor.min.js',
      options: {
        plugin: [
          [
            'minifyify', {
              map: 'vendor.min.js.map',
              output: './js/vendor.min.js.map'
            }
          ]
        ],
        require: VENDOR_LIBRARIES
      }
    };
  }

  config.sass = {
    options: {
      outputStyle: 'compressed',
      sourceMap: true,
      includePaths: [ 'sass/', 'node_modules/swiper/dist/css', 'node_modules/trib-styles/sass/', '_blueprint/base-sass/' ]
    },
    app: {
      files: {
        'css/riots-base.css': 'sass/riots-base.scss',
        'css/vignettes.css': 'sass/vignettes.scss',
        'css/story.css': 'sass/story.scss'
      }
    }
  };

  config.postcss = {
    options: {
      processors: [
        require('autoprefixer')() 
      ]
    },
    dist: {
      src: 'css/*.css'
    }
  }

  config.watch = {
    sass: {
      files: ['sass/**/*.scss', '_blueprint/**/*.scss'],
      tasks: ['sass', 'postcss']
    },
    js: {
      files: ['js/src/**/*.js'],
      tasks: ['browserify']
    }
  };

  grunt.initConfig(config);

  grunt.loadNpmTasks('grunt-sass');
  grunt.loadNpmTasks('grunt-browserify');
  grunt.loadNpmTasks('grunt-contrib-watch');
  grunt.loadNpmTasks('grunt-postcss');

  var defaultTasks = [];

  defaultTasks.push('sass');
  defaultTasks.push('browserify');
  defaultTasks.push('postcss');

  grunt.registerTask('default', defaultTasks);
};