releases

The Release Process

This document explains the Symfony release process (Symfony being the code

hosted on the main symfony/symfony `Git repository`_).

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*.

.. note::

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.

Development

The six-months period is divided into two phases:

* *Development*: *Four months* to add new features and to enhance existing

ones;

* *Stabilisation*: *Two months* to fix bugs, prepare the release, and wait

for the whole Symfony ecosystem (third-party libraries, bundles, and

projects using Symfony) to catch up.

During the development phase, any new feature can be reverted if it won't be

finished in time or if it won't be stable enough to be included in the current

final release.

Maintenance

Each Symfony version is maintained for a fixed period of time, depending on

the type of the release.

Standard Releases

A standard release is maintained for an *eight month* period.

Long Term Support Releases

Every two years, a new Long Term Support Release (aka LTS release) is

published. Each LTS release is supported for a *three year* period.

.. note::

Paid support after the three year support provided by the community can

also be bought from `SensioLabs`_.

Schedule

Below is the schedule for the first few versions that use this release model:

.. image:: /images/release-process.jpg

:align: center

* *(special)* Symfony 2.2 will be released at the end of February 2013;

* *(special)* Symfony 2.3 (the first LTS) will be released at the end of May

2013;

* Symfony 2.4 will be released at the end of November 2013;

* Symfony 2.5 will be released at the end of May 2014;

* ...

Backward Compatibility

After the release of Symfony 2.3, backward compatibility will be kept at all

cost. If it is not possible, the feature, the enhancement, or the bug fix will

be scheduled for the next major version: Symfony 3.0.

.. note::

The work on Symfony 3.0 will start whenever enough major features breaking

backward compatibility are waiting on the todo-list.

Rationale

This release process was adopted to give more *predictability* and

*transparency*. Is was discussed based on the following goals:

* Shorten the release cycle (allow developers to benefit from the new

features faster);

* Give more visibility to the developers using the framework and Open-Source

projects using Symfony;

* Improve the experience of Symfony core contributors: everyone knows when a

feature might be available in Symfony.

* Coordinate the Symfony timeline with popular PHP projects that work well

with Symfony and with projects using Symfony;

* Give time to the Symfony ecosystem to catch up with the new versions

(bundle authors, documentation writers, translators, ...).

The six month period was chosen as two releases fit in a year. It also gives

plenty of time to work on new features and it also allows for non-ready

features to be postponed to the next version without having to wait too much

for the next cycle.

The dual maintenance mode was adopted to make every Symfony user happy. Fast

movers, who want to work with the latest and the greatest, use the standard

releases: a new version is published every six months, and there is a two

months period to upgrade. Companies wanting more stability use the LTS

releases: a new version is published every two years and there is a year to

upgrade.

.. _Git repository: https://github.com/symfony/symfony

.. _SensioLabs: http://sensiolabs.com/

* :doc:`Release Process </contributing/community/releases>`