Overleaf/services/web/babel.config.json

{
  "presets": [
    [
      "@babel/react",
      {
        "runtime": "automatic"
      }
    ],
    [
      "@babel/env",
      {
        "useBuiltIns": "usage",
        // This version must be aligned with the `core-js` version in `package.json`
        "corejs": { "version": 3.6 }
      }
    ]
  ],
  "plugins": ["angularjs-annotate", "macros"],
  // Target our current Node version in test environment, to transform and
  // polyfill only what's necessary
  "env": {
    "test": {
      "presets": [
        [
          "@babel/react",
          {
            "runtime": "automatic"
          }
        ],
        [
          "@babel/env",
          {
            "targets": { "node": "12.21" },
            "useBuiltIns": "usage",
            // This version must be aligned with the `core-js` version in `package.json`
            "corejs": { "version": 3.6 }
          }
        ]
      ]
    }
  }
}