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CONTRIBUTING.md

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+# Contribute to Doctrine
+
+Thank you for contributing to Doctrine. Before we can merge your Pull-Request
+here are some guidelines that you need to follow:
+
+## Coding Standard
+
+We use PSR-1 and PSR-2:
+
+* https://github.com/php-fig/fig-standards/blob/master/accepted/PSR-1-basic-coding-standard.md
+* https://github.com/php-fig/fig-standards/blob/master/accepted/PSR-2-coding-style-guide.md
+
+with some exceptions/differences:
+
+* Keep the nesting of control structures per method as small as possible
+* Align equals (=) signs
+* Add spaces between assignment, control and return statements
+* Prefer early exit over nesting conditions
+* Add spaces around a negation if condition ``if ( ! $cond)``
+
+## Unit-Tests
+
+You can run the unit-tests by calling ``phpunit`` from the root of the project.
+It will run all the tests with an in memory SQLite database.
+
+To run the testsuite against another database, copy the ``phpunit.xml.dist``
+to for example ``mysql.phpunit.xml`` and edit the parameters. You can
+take a look at the ``tests/travis`` folder for some examples. Then run:
+
+    phpunit -c mysql.phpunit.xml
+
+## Travis
+
+We automatically run your pull request through [Travis CI](http://www.travis-ci.org)
+against SQLite, MySQL and PostgreSQL. If you break the tests, we cannot merge your code.
+
+## DoctrineBot, Tickets and Jira
+
+DoctrineBot will synchronize your Pull-Request into our [Jira](http://www.doctrine-project.org).
+Make sure to add any existing Jira ticket into the Pull-Request Title, for example:
+
+    "[DDC-123] My Pull Request"
+
+## Getting merged
+
+Please allow us time to review your pull requests. We will give our best to review
+everything as fast as possible, but cannot always live up to our own expectations.
+
+Thank you very much again for your contribution!
+