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CONTRIBUTING.md

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+# How to contribute
+
+In the spirit of open source software, **everyone** is encouraged to help
+improve this project.
+
+## Your Pull Request
+
+To make it easy to review and understand your change please keep the following
+things in mind before submitting your pull request:
+
+* Work on the latest possible state of **ginatra/master**
+* Create a branch which is dedicated to your change
+* Test your changes before creating a pull request (`bundle exec rake`)
+* If possible write a test case which confirms your change
+* Don't mix several features or bug-fixes in one pull request
+* Create a meaningful commit message
+* Explain your change (i.e. with a link to the issue you are fixing)
+* Keep it simple: don't overcomplicate things and add extra dependencies unless
+  you have a *special* reason
+
+**IMPORTANT**:
+
+Before you start working on a larger contribution, you should get in touch first
+through the issue tracker with your idea so that the project's developers can
+help out and possibly guide you. Coordinating up front makes it much easier to
+avoid frustration later on.
+
+# Thank you
+
+Each contribution is extremely helpful - thank you!