gulp + coffee + sass + watch + minify + cache buster sample

.gitignore

/node_modules
*.map
/bower_components

Gulpfile.coffee

gulp       = require 'gulp'
watch      = require 'gulp-watch'
sass       = require 'gulp-sass'
coffee     = require 'gulp-coffee'
plumber    = require 'gulp-plumber'
sourcemaps = require 'gulp-sourcemaps'
uglify     = require 'gulp-uglify'
minifycss  = require 'gulp-minify-css'
concat     = require 'gulp-concat'
buster     = require 'gulp-buster'
rename     = require 'gulp-rename'
del        = require 'del'
path       = require 'path'
bower      = require 'main-bower-files'

src =
  coffee: 'src/**/*.coffee',
  scss:   'src/**/*.scss'
dest =
  css:     'stylesheets/application.css',
  js:      'javascripts/application.js',
  css_dir: 'stylesheets',
  js_dir:  'javascripts'
bower_dest =
  eot:  'fonts',
  svg:  'fonts',
  ttf:  'fonts',
  woff: 'fonts',
  js:   'javascripts/lib',
  css:  'stylesheets/lib',
  scss: 'src'

gulp.task 'build', ['bower:install', 'rename']

gulp.task 'bower:install', ['clean'], ->
  bower().forEach (file)->
    gulp.src file
    .pipe gulp.dest bower_dest[(path.extname file).replace(/^\./, '')]

gulp.task 'rename', ['buster'], ->
  busters = require './busters.json'
  gulp.src dest.js
  .pipe rename "application." + busters[dest.js] + ".js"
  .pipe gulp.dest dest.js_dir
  gulp.src dest.css
  .pipe rename "application." + busters[dest.css] + ".css"
  .pipe gulp.dest dest.css_dir

gulp.task 'buster', ['uglifyjs', 'minify-css'], ->
  gulp.src [dest.js, dest.css]
  .pipe buster('busters.json')
  .pipe gulp.dest '.'

gulp.task 'uglifyjs', ['coffee'], ->
  gulp.src [bower_dest.js + '/*.js', dest.js_dir + '/*.js']
  .pipe plumber()
  .pipe uglify preserveComments: 'some'
  .pipe concat 'application.js'
  .pipe gulp.dest dest.js_dir

gulp.task 'minify-css', ['concat-css'], ->
  gulp.src dest.css
  .pipe minifycss()
  .pipe gulp.dest dest.css_dir

gulp.task 'concat-css', ['sass'], ->
  gulp.src [bower_dest.css + '/*.css', dest.css_dir + '/*.css']
  .pipe plumber()
  .pipe concat 'application.css'
  .pipe gulp.dest dest.css_dir

gulp.task 'clean', ->
  del.sync [dest.css_dir, dest.js_dir]

gulp.task 'compile', ['coffee', 'sass']

gulp.task 'watch', ['compile'], ->
  gulp.watch src.coffee, ['coffee']
  gulp.watch src.scss, ['sass']

gulp.task 'coffee', ->
  gulp.src src.coffee
  .pipe plumber()
  .pipe sourcemaps.init()
  .pipe coffee {bare: true}
  .pipe sourcemaps.write './maps'
  .pipe gulp.dest dest.js_dir

gulp.task 'sass', ->
  gulp.src src.scss
  .pipe plumber()
  .pipe sass({sourcemap: true})
  .pipe gulp.dest dest.css_dir

package.json

{
  "devDependencies": {
    "grunt":           "*",
    "gulp":            "*",
    "coffee-script":   "*",
    "gulp-coffee":     "*",
    "gulp-sass":       "*",
    "gulp-watch":      "*",
    "gulp-plumber":    "*",
    "gulp-sourcemaps": "*",
    "gulp-uglify":     "*",
    "gulp-minify-css": "*",
    "gulp-concat":     "*",
    "gulp-buster":     "*",
    "gulp-rename":     "*",
    "del":             "*",
    "main-bower-files": "*"
  }
}