guard で *.less と *.coffee 監視してコンパイル

Gemfile

source 'http://rubygems.org'

gem 'guard'
gem 'guard-less'
gem 'guard-coffeescript'

Guardfile

# -*- coding: utf-8 -*-

guard :less, output: 'public/stylesheets', import_paths: ['assets/less'] do
  watch %r{assets/less/.+\.less}
end

guard :coffeescript, output: 'public/javascripts' do
  watch %r{assets/coffeescript/.+\.coffee}
end