* `Install Composer`_, which is used to install PHP packages.

Optionally, you can also `install Symfony CLI`_. This creates a binary called

``symfony`` that provides all the tools you need to develop and run your

Symfony application locally.

.. _setup-symfony-cli:

Also, `install the Symfony CLI`_. This is optional, but it gives you a

helpful binary called ``symfony`` that provides all tools you need to

develop and run your Symfony application locally.

The ``symfony`` binary also provides a tool to check if your computer meets all

requirements. Open your console terminal and run this command:

The only difference between these two commands is the number of packages

installed by default. The ``--webapp`` option installsall thepackagesthat you

usuallyneed to build webapplications, so the installation size will be bigger.

installed by default. The ``--webapp`` option installsextrapackagesto give

you everything youneed to buildawebapplication.

If you're not using the Symfony binary, run these commands to create the new

Symfony application using Composer:

Checking Security Vulnerabilities

The ``symfony`` binary created when you`installSymfony CLI`_ provides a command

to check whether your project's dependencies contain any known security

The ``symfony`` binary created when youinstalled the:ref:`Symfony CLI<setup-symfony-cli>`

provides a commandto check whether your project's dependencies contain any known security

vulnerability:

..code-block::terminal

.. _`Stellar Development with Symfony`:https://symfonycasts.com/screencast/symfony

.. _`Install Composer`:https://getcomposer.org/download/

.. _`install Symfony CLI`:https://symfony.com/download

.. _`installtheSymfony CLI`:https://symfony.com/download

.. _`symfony-cli/symfony-cli GitHub repository`:https://github.com/symfony-cli/symfony-cli

.. _`The Symfony Demo Application`:https://github.com/symfony/demo

.. _`Symfony Flex`:https://github.com/symfony/flex