Roadmap for version 3.0

We are planning to release Create React App version 3.0 soon. This will be a relatively small release but will include a number of necessary breaking changes.

Planned Features

• Jest 24: https://github.com/facebook/create-react-app/pull/6278
• Hooks ESLint plugin: https://github.com/facebook/create-react-app/pull/5997
• TypeScript ESLint plugin https://github.com/facebook/create-react-app/pull/6513
• Add browserslist support to @babel/preset-env: #6608
• Absolute imports using jsconfig.json/tsconfig.json: https://github.com/facebook/create-react-app/pull/6656

Nice to Have Features

• babel-plugin-optimize-react: https://github.com/facebook/create-react-app/pull/6219

Refer to the 3.0 Milestone to see exactly what is included in this release.

☢️ How Can I Test This Now? ☢️

We’re happy you’d like to test the next version of react-scripts! Before getting into the details, we’d like to make you aware of a few things:

1. Features may be broken or not work as expected
2. There will be more breaking changes introduced before the final release ⚠️
3. Documentation for new features is still sparse, so look through the pull requests for how they’re expected to work

You can install the latest alpha version of react-scripts using one of the following commands:

$ # Create a new application
$ npx create-react-app@next --scripts-version=3.0.0-next.68 app-name
$ # Upgrade an existing application
$ yarn upgrade react-scripts@3.0.0-next.68

Upgrading from 2.0 to 3.0

• The browserslist config in your package.json is now used to control the output of your JavaScript files. You can use separate configuration for development and production. See https://github.com/facebook/create-react-app/blob/b0cbf2caa18ee8267855b14578ebc3dee826f552/packages/react-scripts/package.json#L83-L94 for a good starting point which gives a good development experience, especially when using language features such as async/await, but still provides high compatibility with many browsers in production

• We now have linting support for TypeScript files! If you’re using Visual Studio Code, see https://github.com/facebook/create-react-app/blob/master/docusaurus/docs/setting-up-your-editor.md#displaying-lint-output-in-the-editor for tips to get syntax highlighting from the ESLint extension in your .ts and .tsx files

• We now support setting basePath in jsconfig.json. To configure basePath to point to the src directory create a jsconfig.json file in your project root:

  {
    "compilerOptions": {
      "baseUrl": "src"
    }
  }
  

Known Issues in 3.0 Alphas

• File watching issue with Jest 24: #6646
• Dynamic imports may not work in some cases: #6673

Please report any bugs you encounter or behavior you believe to be incorrect by creating a new issue. Have fun!

[iansu]

We just published Create React App 3.0! See the release notes for details about everything that’s included and instructions on upgrading your apps.

Big thanks to everyone who contributed to this release and helped test the alphas! 🎉

[amshtemp]

It would be nice if these two css features get included too:

• Support scoped CSS in the same file (https://github.com/facebook/create-react-app/issues/5224)
• CSS Modules with TypeScript: css-modules-typescript-loader (#5677)