{
  "name": "es2017-functions",
  "description": "Sample app showing how to transpile ES7 code in cloud Functions.",
  "dependencies": {
    "babel-runtime": "^6.23.0",
    "firebase-admin": "^4.1.1",
    "firebase-functions": "^0.5.1"
  },
  "devDependencies": {
    "babel-cli": "^6.26.0",
    "babel-plugin-transform-runtime": "^6.23.0",
    "babel-preset-env": "^1.6.1",
    "babel-plugin-transform-object-rest-spread": "^6.26.0"
  },
  "scripts": {
    "prepare": "babel ./*.es7 --presets latest --retain-lines -d ./"
  }
}

{
  "name": "es2017-functions",
  "description": "Sample app showing how to transpile ES7 code in cloud Functions.",
  "dependencies": {
    "babel-runtime": "^6.23.0",
    "firebase-admin": "^4.1.1",
    "firebase-functions": "^0.5.1"
  },
  "devDependencies": {
    "babel-cli": "^6.26.0",
    "babel-plugin-transform-runtime": "^6.23.0",
    "babel-preset-env": "^1.6.1",
    "babel-plugin-transform-object-rest-spread": "^6.26.0"
  },
  "scripts": {
    "prepare": "babel ./*.es7 --retain-lines -d ./"
  }
}

Remove explicit presets in Babel CLI call
Remove explicit presets in Babel CLI call