# babel-preset-react-app This package includes the Babel preset used by [Create React App](https://github.com/facebook/create-react-app).
Please refer to its documentation: - [Getting Started](https://facebook.github.io/create-react-app/docs/getting-started) – How to create a new app. - [User Guide](https://facebook.github.io/create-react-app/) – How to develop apps bootstrapped with Create React App. ## Usage in Create React App Projects The easiest way to use this configuration is with [Create React App](https://github.com/facebook/create-react-app), which includes it by default. **You don’t need to install it separately in Create React App projects.** ## Usage Outside of Create React App If you want to use this Babel preset in a project not built with Create React App, you can install it with the following steps. First, [install Babel](https://babeljs.io/docs/setup/). Then install babel-preset-react-app. ```sh npm install babel-preset-react-app --save-dev ``` Then create a file named `.babelrc` with following contents in the root folder of your project: ```json { "presets": ["react-app"] } ``` This preset uses the `useBuiltIns` option with [transform-object-rest-spread](https://babeljs.io/docs/plugins/transform-object-rest-spread/) and [transform-react-jsx](https://babeljs.io/docs/plugins/transform-react-jsx/), which assumes that `Object.assign` is available or polyfilled. ## Usage with Flow Make sure you have a `.flowconfig` file at the root directory. You can also use the `flow` option on `.babelrc`: ```json { "presets": [["react-app", { "flow": true, "typescript": false }]] } ``` ## Usage with TypeScript Make sure you have a `tsconfig.json` file at the root directory. You can also use the `typescript` option on `.babelrc`: ```json { "presets": [["react-app", { "flow": false, "typescript": true }]] } ``` ## Absolute Runtime Paths Absolute paths are enabled by default for imports. To use relative paths instead, set the `absoluteRuntime` option in `.babelrc` to `false`: ``` { "presets": [["react-app", { "absoluteRuntime": false }]] } ```