Composer
Composer is PHP's dependency manager. It downloads packages from Packagist, autoloads classes, and manages version constraints.
PHP
Beginner
3 min read
Introduction to Composer
Example
# Install Composer globally
curl -sS https://getcomposer.org/installer | php
mv composer.phar /usr/local/bin/composer
# Create a new project
composer init
# Install a package
composer require guzzlehttp/guzzle
# Install dev dependency
composer require --dev phpunit/phpunit Pro Tip
composer.lock records exact installed versions — always commit it to version control.