Gulpfile for CMS integration (Drupal, Wordpress, Umbraco Sitecore etc.) Includes task for Sass + Autoprefixer, Styleguide (KSS) and JS Uglifier.

gulpfile.js

'use strict';

var gulp        = require('gulp'),
    concat      = require('gulp-concat'),
    sass        = require('gulp-sass'),
    uglify      = require('gulp-uglify'),
    watch       = require('gulp-watch'),
    prefix      = require('gulp-autoprefixer'),
    del         = require('del'),
    kss         = require('gulp-kss'),
    changed     = require('gulp-changed');


//
// Paths
// -------------------------------------------------------------

    // If project root is not inside a folder then change it to './'
var ROOT               = './project-name/',    
    ASSETS             = ROOT + 'assets/',
    SOURCE             = ASSETS + 'source/',
    BUILD              = ASSETS + 'build/',
    BOWER              = 'bower_components/',
    STYLEGUIDETEMPLATE = SOURCE + 'styleguide-template/',

    // Combine these with either BUILD or SOURCE
    STYLES             = 'styles/',
    JS                 = 'scripts/',
    IMAGES             = 'images/',
    FONTS              = 'fonts/';


//
// TASKS
// -------------------------------------------------------------
gulp.task('css', function() {
  watch({glob: SOURCE + STYLES + '*.scss'}, function(files) {
    return files.pipe(sass({
        errLogToConsole: true
      }))
      .pipe(prefix('last 1 version', '> 1%', 'ie 9').on('error', function (error) {
        console.warn(error.message);
      }))
      .pipe(gulp.dest(BUILD + STYLES));
  });
});

gulp.task('js', function() {
  return gulp.src([
      BOWER + 'jquery/dist/jquery.js',
      SOURCE + JS + '*.js'
    ])
    .pipe(concat('main.js'))
    .pipe(uglify().on('error', function (error) {
      console.warn(error);
    }))
    .pipe(gulp.dest(BUILD + JS));
});

gulp.task('images', function() {
  watch({glob: SOURCE + IMAGES + '*.*'}, function(files) {
    return files.pipe(
        gulp.dest(BUILD + IMAGES)
      );
  });
});

gulp.task('fonts', function() {
  watch({glob: SOURCE + FONTS + '*.*'}, function(files) {
    return files.pipe(
        gulp.dest(BUILD + FONTS)
      );
  });
});

gulp.task('vendor', function() {
  return gulp.src([
      BOWER + 'modernizr/modernizr.js',
      BOWER + 'respond/src/respond.js'
    ])
    .pipe(concat('vendor.js'))
    .pipe(uglify())
    .pipe(gulp.dest(BUILD + JS));
});

gulp.task('clean', function(cb){
  return del([BUILD], cb);
});

gulp.task('kss', function() {
  return gulp.src([SOURCE + STYLES + '**/*.scss'])
    .pipe(kss({
      overview: 'README.md',
      templateDirectory: STYLEGUIDETEMPLATE
    }))
    .pipe(gulp.dest(ROOT + 'styleguide/'));
});

// --- Bringing it all together in a build task ---
gulp.task('build', [
  'js',
  'css',
  'images',
  'fonts',
  'kss',
  'vendor'
]);


// --- Let gulp keep an eye on our files and compile stuff if it changes ---
gulp.task('watch', ['build'], function () {
  gulp.watch(SOURCE + STYLES + '**/*.scss',['css', 'kss']);

  gulp.watch(SOURCE + JS + '*.js',['js']);

  gulp.watch(SOURCE + IMAGES + '*.*',['images']);

  gulp.watch([SOURCE + 'styleguide-template/**/*.*', 'README.md'],['kss']);
});


// --- Default gulp task, run with gulp.
gulp.task('default', ['clean'], function(){
  gulp.start('watch');
});

Use this as a continuation from e.g.: https://github.com/chriskjaer/prototype-seed
Get the bower.json, package.json and styleguide-template base from there as well if necessary.