Symfony aims to speed up the creation and maintenance of web applications and to replace repetitive coding tasks.
Symfony has a low performance overhead used with a bytecode cache.
Symfony is aimed at building robust applications in an enterprise context, and aims to give developers full control over the configuration: from the directory structure to the foreign libraries, almost everything can be customized. To match enterprise development guidelines, Symfony is bundled with additional tools to help developers test, debug and document projects.
Symfony makes heavy use of existing PHP open-source projects as part of the framework, including:
- Propel or Doctrine as object-relational mapping layers
- PDO database abstraction layer (1.1, with Doctrine and Propel 1.3)
- PHPUnit, a unit testing framework
- Twig, a templating engine
- Swift Mailer, an e-mail library
Symfony also makes use of its own components, which are freely available on the for various other projects:
- , a YAML parser based upon Spyc
- , a dependency injector
- , a templating engine
- Prototype or jQuery
- script.aculo.us, for visual effects
- , a Less-to-CSS converter
- TinyMCE or CKEditor, for rich text editing
- TCPDF, a PHP library for generating PDF documents
Symfony is sponsored by SensioLabs, a French software developer and professional services provider. The first name was Sensio Framework, and all classes were prefixed with sf. Later on when it was decided to launch it as open source framework, the brainstorming resulted in the name symfony (being renamed to Symfony from version 2 and on), the name which depicts the theme and class name prefixes.
- Symfony is used by the open-source Q&A service Askeet and many more applications, including Delicious.
- At one time it was used for 20 million users of .
- As of February 2009, Dailymotion.com has ported part of its code to use Symfony, and is continuing the transition.
- Symfony2 is used by , a social shopping platform, and the Symfony framework is also used by the massively multiplayer online browser game eRepublik, and by the content management framework eZ Publish in version 5.
- Drupal 8, phpBB and a number of other large applications have incorporated components of Symfony.
- Symfony2 is also used by , one of the largest online dating platforms in the world, on most of its websites for implementing its business logic in the backend.
- Symfony components are also used in other web application frameworks including Laravel, which is another full stack framework, and Silex, which is a microframework.
- As of February 12, 2013 the massive wiki-database video game website GiantBomb.com converted from Django to Symfony following an acquisition.
- Vogue France's website is also built on the Symfony framework
Symfony's own website has a comprehensive showcase of sites:
|Red||Release no longer supported|
|Green||Release still supported|
Symfony manages its releases through a time-based model; a new Symfony release comes out every six months: one in May and one in November.
This release process has been adopted as of Symfony 2.2, and all the "rules" explained in this document must be strictly followed as of Symfony 2.4.
|Version||Release date||Support||PHP version||End of maintenance||Notes|
|1.0||January 2007||Three years||≥ 5.0||January 2010|
|1.1||June 2008||One year||≥ 5.1||June 2009||Security-related patches were applied until June 2010|
|1.2||December 2008||One year||≥ 5.2||November 2009|
|1.3||November 2009||One year||≥ 5.2.4||November 2010|
|1.4||November 2009||Three years||≥ 5.2.4||November 2012||LTS version. 1.4 is identical to 1.3, but it does not support the 1.3 deprecated features.|
|2.0||July 2011||≥ 5.3.2||March 2013||Last 2.0.x release was Symfony 2.0.25|
|2.1||September 2012||Eight months||≥ 5.3.3||June 2013||More components are part of the stable API.|
|2.2||March 2013||Eight months||≥ 5.3.3||November 2013||Various new features.|
|2.3||June 2013||Three years||≥ 5.3.3||May 2016||The first LTS release, only three months development, normally six months.|
|2.4||November 2013||Eight months||≥ 5.3.3||July 2014||The first 2.x branch release with complete backwards compatibility.|
|2.5||May 2014||Eight months||≥ 5.3.3||January 2015|
|2.6||November 2014||Eight months||≥ 5.3.3||July 2015|
|2.7||May 2015||Three years||≥ 5.3.9||May 2018||LTS release.|
|2.8||November 2015||Three years||≥ 5.3.9||November 2018||LTS release.|
|3.0||November 2015||Eight months||≥ 5.5.9||July 2016|
|3.1||May 2016||Eight months||≥ 5.5.9||January 2017|
|3.2||November 2016||Eight months||≥ 5.?.?||July 2017|
|3.3||May 2017||Eight months||≥ 5.?.?||January 2018|
|3.4||November 2017||Three years||≥ 5.?.?||November 2020||LTS release.|