overleaf/services/web/babel.config.json

{
  "presets": [
    [
      "@babel/env",
      {
        "useBuiltIns": "usage",
        // This version must be aligned with the `core-js` version in `package.json`
        "corejs": { "version": "3.30" },
        "exclude": [
          // Exclude Array.prototype.push polyfill, as it's not needed and affects performance in Chrome
          "es.array.push",
          // Exclude objectSpread polyfill, as it's not needed and affects performance
          "@babel/plugin-transform-object-rest-spread",
          // Exclude _defineProperty polyfill, as it causes a bug without the objectSpread polyfill
          "@babel/plugin-transform-computed-properties",
          // Use native async functions, for performance
          "@babel/plugin-transform-async-to-generator",
          // Use native generators, for performance
          "@babel/plugin-transform-regenerator",
          // Use native async generators, for performance
          "@babel/plugin-transform-async-generator-functions",
          // Use native for-of loops, for performance
          "@babel/plugin-transform-for-of"
        ]
      }
    ],
    ["@babel/react", { "runtime": "automatic" }],
    "@babel/typescript"
  ],
  "plugins": ["macros"],
  "overrides": [
    // treat .cjs files (e.g. libraries symlinked into node_modules) as commonjs
    {
      "test": "../../**/*.cjs",
      "sourceType": "script"
    },
    {
      "test": "../../libraries/overleaf-editor-core/**/*.js",
      "sourceType": "script"
    }
  ]
}