Composer – the PHP dependency manager

Inspired by npm (https://www.npmjs.com/) and bundler (http://bundler.io/), Composer (https://getcomposer.org/) manages the dependencies of your project and installs packages in predetermined directories (for example, vendor) using the composer.json file in the Magento module or theme. This kind of management is very useful once each library has your specific dependency. Composer doesn't let you waste your time by connecting the dependencies to every deployment that you want to do.

In the next chapters, we will use Composer to install components on Magento. However, first, we will start the development of our theme; it is necessary to declare our composer.json file. For now, let's install Composer on the operating system.

Installing Composer on Unix-like operating systems

To install Composer on Unix-like systems (such as Unix, Linux, and OS X), you simply need to run these two commands in the terminal:

$ curl -s https://getcomposer.org/installer | php...