# Yarn Package Manager

Yarn is a package manager for Node.js, similar to npm. While sharing a lot of common ground, there are some key differences between Yarn and npm.

# Creating a basic package

The yarn init command will walk you through the creation of a package.json file to configure some information about your package. This is similar to the npm init command in npm.

Create and navigate to a new directory to hold your package, and then run yarn init

mkdir my-package && cd my-package
yarn init

Answer the questions that follow in the CLI

question name (my-package): my-package
question version (1.0.0): 
question description: A test package
question entry point (index.js): 
question repository url: 
question author: StackOverflow Documentation
question license (MIT): 
success Saved package.json
✨  Done in 27.31s.

This will generate a package.json file similar to the following

{
  "name": "my-package",
  "version": "1.0.0",
  "description": "A test package",
  "main": "index.js",
  "author": "StackOverflow Documentation",
  "license": "MIT"
}

Now lets try adding a dependency. The basic syntax for this is yarn add [package-name]

Run the following to install ExpressJS

yarn add express

This will add a dependencies section to your package.json, and add ExpressJS

"dependencies": {
    "express": "^4.15.2"
}

# Yarn Installation

This example explains the different methods to install Yarn for your OS.

# macOS

# Homebrew

brew update
brew install yarn

# MacPorts

sudo port install yarn

# Adding Yarn to your PATH

Add the following to your preferred shell profile (.profile, .bashrc, .zshrc etc)

export PATH="$PATH:`yarn global bin`"

# Windows

# Installer

First, install Node.js if it is not already installed.

Download the Yarn installer as an .msi from the Yarn website.

# Chocolatey

choco install yarn

# Linux

# Debian / Ubuntu

Ensure Node.js is installed for your distro, or run the following

curl -sL https://deb.nodesource.com/setup_6.x | sudo -E bash -
sudo apt-get install -y nodejs

Configure the YarnPkg repository

curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | sudo apt-key add -
echo "deb https://dl.yarnpkg.com/debian/ stable main" | sudo tee /etc/apt/sources.list.d/yarn.list

Install Yarn

sudo apt-get update && sudo apt-get install yarn

# CentOS / Fedora / RHEL

Install Node.js if not already installed

curl --silent --location https://rpm.nodesource.com/setup_6.x | bash -

Install Yarn

sudo wget https://dl.yarnpkg.com/rpm/yarn.repo -O /etc/yum.repos.d/yarn.repo
sudo yum install yarn

# Arch

Install Yarn via AUR.

Example using yaourt:

yaourt -S yarn

# Solus

sudo eopkg install yarn

# All Distributions

Add the following to your preferred shell profile (.profile, .bashrc, .zshrc etc)

export PATH="$PATH:`yarn global bin`"

# Alternative Method of Installation

# Shell script

curl -o- -L https://yarnpkg.com/install.sh | bash

or specify a version to install

curl -o- -L https://yarnpkg.com/install.sh | bash -s -- --version [version]

# Tarball

cd /opt
wget https://yarnpkg.com/latest.tar.gz
tar zvxf latest.tar.gz

# Npm

If you already have npm installed, simply run

npm install -g yarn

# Post Install

Check the installed version of Yarn by running

yarn --version

# Install package with Yarn

Yarn uses the same registry that npm does. That means that every package that is a available on npm is the same on Yarn.

To install a package, run yarn add package.

If you need a specific version of the package, you can use yarn add package@version.

If the version you need to install has been tagged, you can use yarn add package@tag.