npx create-react-app@next --scripts-version=@next --template=cra-template@next my-js-app
npx create-react-app@next --scripts-version=@next --template=typescript@next my-ts-app
To update an existing app you can change the react-scripts
version in package.json
to next
and then run yarn
or npm install
You can see a list of all the changes in the 4.0 release here
I have one app that's started having very odd behavior in tests with the upgrade. I'll put together a repro asap.
It's this one: https://github.com/kentcdodds/react-performance