

The build is minified and the filenames include the hashes. It correctly bundles React in production mode and optimizes the build for the best performance. npm run buildīuilds the app for production to the build folder. See the section about running tests for more information.

Launches the test runner in the interactive watch mode. You will also see any lint errors in the console. In the project directory, you can run: npm start They will not be included in the production build so you can use them for things like documentation. You can, however, create more top-level directories. Read instructions below for using assets from JavaScript and HTML. Only files inside public can be used from public/index.html. You need to put any JS and CSS files inside src, or Webpack won’t see them. For faster rebuilds, only files inside src are processed by Webpack. You may create subdirectories inside src. You can delete or rename the other files.

We commit to keeping the breaking changes minimal so you can upgrade react-scripts painlessly. In most cases bumping the react-scripts version in package.json and running npm install in this folder should be enough, but it’s good to consult the changelog for potential breaking changes. To update an existing project to a new version of react-scripts, open the changelog, find the version you’re currently on (check package.json in this folder if you’re not sure), and apply the migration instructions for the newer versions. When you run create-react-app, it always creates the project with the latest version of react-scripts so you’ll get all the new features and improvements in newly created apps automatically. You almost never need to update create-react-app itself: it delegates all the setup to react-scripts.
