old_contents: var gulp = require('gulp');
  var config = require('../config.js');
  var mergeStream = require('merge-stream');
  var minifyCSS = require('gulp-minify-css');
  var plugins = require('gulp-load-plugins')();
  
  gulp.task('styles', function () {
      var streams = config.bundles.filter(function (b) {
          return b.styles != null;
      }).map(function (b) {
          var ignores = b.ignorePlugins != null ? b.ignorePlugins : [];
  
          var useSourcemaps = ignores.indexOf("sourcemaps") == -1;
          var useAutoprefixer = ignores.indexOf("autoprefixer") == -1;
  
          return gulp.src(b.styles)
              .pipe(plugins.plumber(config.errorHandler("styles")))
              .pipe(plugins.if(useSourcemaps, plugins.sourcemaps.init({ loadMaps: true })))
              .pipe(plugins.less())
              .pipe(plugins.concat(b.name + ".min.css"))
              .pipe(plugins.if(useAutoprefixer, plugins.autoprefixer(config.stylesVendorPrefixes)))
              .pipe(minifyCSS({keepBreaks:false}))
              .pipe(plugins.if(useSourcemaps, plugins.sourcemaps.write('.')))
              .pipe(gulp.dest(config.stylesDist));
      });
  
      return mergeStream(streams);
  });
new_contents: var gulp = require('gulp');
  var config = require('../config.js');
  var mergeStream = require('merge-stream');
  var plugins = require('gulp-load-plugins')();
  
  gulp.task('styles', function () {
      var streams = config.bundles.filter(function (b) {
          return b.styles != null;
      }).map(function (b) {
          var ignores = b.ignorePlugins != null ? b.ignorePlugins : [];
  
          var useSourcemaps = ignores.indexOf("sourcemaps") == -1;
          var useAutoprefixer = ignores.indexOf("autoprefixer") == -1;
  
          return gulp.src(b.styles)
              .pipe(plugins.plumber(config.errorHandler("styles")))
              .pipe(plugins.if(useSourcemaps, plugins.sourcemaps.init({ loadMaps: true })))
              .pipe(plugins.less())
              .pipe(plugins.concat(b.name + ".min.css"))
              .pipe(plugins.if(useAutoprefixer, plugins.autoprefixer(config.stylesVendorPrefixes)))
              .pipe(plugins.minifyCss({keepBreaks:false}))
              .pipe(plugins.if(useSourcemaps, plugins.sourcemaps.write('.')))
              .pipe(gulp.dest(config.stylesDist));
      });
  
      return mergeStream(streams);
  });
  
subject: Update styles.js