How to switch from Yarn 1 to Yarn 4!

Finally a simple guide on how to switch to using yarn berry without losing track of your goal.

Introduction

Yarn is a popular package manager for JavaScript projects that offers speed, reliability, and a range of powerful features. If you’ve been using Yarn 1 (also known as Yarn Classic) and want to upgrade to Yarn 4 (or later versions), you’re making a smart choice. Yarn 4 brings numerous improvements, including enhanced performance, better security, and a more user-friendly interface. In this article, we’ll guide you through the process of switching from Yarn 1 to Yarn 4.

Before We Begin

Before you start the migration process, it’s essential to ensure that your project is version-controlled using a tool like Git. This will help you to roll back any changes if something goes wrong during the migration process.

Step 1: check your Yarn version

This command will install Yarn 4 as a global package on your system. You can verify the installation by running:

yarn -v

This should return the version number, confirming that Yarn 1 or 4 has been installed successfully. If you didn’t install it already then run: “npm install -g yarn”

Step 2: Set your project to use Berry

Once Yarn 4 is installed, you’ll need to update your project’s Yarn configuration. Navigate to your project’s root directory and run the following command to generate a new Yarn 4 configuration file:

yarn set version berry

This command will create a .yarnrc.yml file in your project directory, which will be used by Yarn 4 to manage your project's dependencies.

Step 3: Upgrade Your Dependencies

To upgrade your project’s dependencies to the latest versions using Yarn 4, you can run:

yarn upgrade-interactive

This command will start an interactive session that allows you to choose which packages to update and to which versions. You can navigate through the list of dependencies using the arrow keys, select the ones you want to update, and then apply the changes. This way, you can ensure that your project’s dependencies are up-to-date and compatible with Yarn 4.

Step 4: Migrate Yarn Workspaces (if applicable)

If your project uses Yarn Workspaces, you will need to update your package.json and yarn.lock files accordingly. Yarn 4 introduces changes to the workspace configuration. Ensure that you update your project's configuration to match the new Yarn 4 format.

You can read more about them here: https://yarnpkg.com/features/workspaces

Resources

• https://github.com/riccardogiorato/template-nextjs-tailwind