Installation will generate a composer.phar file, save it in ./bin folder

curl -sS https://getcomposer.org/installer --output installer
php installer # download composer.phar
			

sudo mv composer.phar /usr/local/bin/composer
			

1. Add "vendor" to .gitignore to instruct Git to ignore all the vendor folder
2. Search required libraries at Packagist
3. Edit composer.json

{
    "require": {
        "monolog/monolog": "1.0.*", 
	"facebook/php-sdk": "3.2.3"
    }
}
			

4. composer install --no-dev, install those dependencies from lock file
5. If add new libraries in composer.json, run "php bin/composer.phar update" to install those libraries
6. require_once 'vendor/autoload.php', add it to your code
7. Check for known security issues by uploading composer.lock file to sensiolabs
8. Build with Grunt and Gulp

composer.lock, store the library versioin information

add your own code to the autoloader

1. Add your code to /src folder

<?php
namespace Acme;
 
class Foo
{
    public static function world()
    {
        return 'Hello World, Composer!';
    }
}
?>
 
			

2. Add autoload field to composer.json

{
    "require": {
        "monolog/monolog": "1.0.*", 
	"facebook/php-sdk": "3.2.3",
	"facebook/webdriver": "1.6.0",
	"facebook/php-sdk-v4": "5.5.0"
    },
 
    "autoload": {
        "psr-4": {"Acme\\": "src/"}
    }
}
			

3. composer install, create new autoload.php
4. Use your own library

<?php
require __DIR__ . '/vendor/autoload.php';
 
use Acme\Foo;
echo Foo::world();
?>
			

PHP Tutorial: Getting Started with Composer

Dependency Manager for PHP

Creating your first Composer/Packagist package

Packagist

Symfony

Laravel