Советую Gulp с libsass. Если не получится настроить, то Grunt - он проще.
Конфиги для Grunt.
gruntfile.js:
module.exports = function(grunt) {
  grunt.loadNpmTasks('grunt-contrib-uglify');
  grunt.loadNpmTasks('grunt-contrib-watch');
  grunt.loadNpmTasks('grunt-contrib-compass');
  grunt.loadNpmTasks('grunt-newer');
  grunt.initConfig({
    uglify: {
      my_target: {
        files: {
          'public_html/js/script.js': ['_/components/js/*.js']
        }
      }
    },
    compass: {
      dev: {
        options: {
          config: 'config.rb'
        }
      }
    },
    watch: {
      options: { livereload: true },
      scripts: {
        files: ['_/components/js/*.js'],
        tasks: ['newer:uglify']
      },
      sass: {
        files: ['_/components/sass/*.scss'],
        tasks: ['compass:dev']
      },
      html: {
        files: ['*.html']
      }
    }
  });
  grunt.registerTask('default', 'watch');
};
config.rb:
#Compass config
require "susy"
require "breakpoint"
css_dir = "public_html/css"
sass_dir = "_/components/sass"
sass_options = {:sourcemap => true}
javascripts_dir = "public_html/js"
output_style = :compressed
# or :nested or :compact or :compressed
Encoding.default_external = "UTF-8"