docs/app.json

{
  "name": "docs.github.com",
  "env": {
    "NODE_ENV": "production",
    "NPM_CONFIG_PRODUCTION": "true",
    "ENABLED_LANGUAGES": "en"
  },
  "buildpacks": [
    { "url": "heroku/nodejs" }
  ],
  "formation": {
    "web": {
      "quantity": 1,
      "size": "standard-2x"
    }
  }
}