babel, sass, npm-run-all

package.json

{
  "devDependencies": {
    "babel-cli": "^6.10.1",
    "babel-preset-es2015": "^6.9.0",
    "babel-preset-stage-0": "^6.5.0",
    "node-sass": "^3.8.0",
    "npm-run-all": "^2.2.2"
  },
  "babel": {
    "presets": [
      "es2015",
      "stage-0"
    ]
  },
  "scripts": {
    "dev": "npm-run-all -s sass:build -p babel sass:watch",
    "babel": "babel -w src/js -d dist/js",
    "sass:build": "node-sass src/css -o dist/css",
    "sass:watch": "node-sass -w src/css -o dist/css"
  }
}