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CONTRIBUTING.md

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+# How to contribute to lego
+
+Contributions in the form of patches and proposals are essential to keep lego great and to make it even better.
+To ensure a great and easy experience for everyone, please review the few guidelines in this document.
+
+## Bug reports
+
+- Use the issue search to see if the issue has already been reported.
+- Also look for closed issues to see if your issue has already been fixed.
+- If both of the above do not apply create a new issue and include as much information as possible.
+
+Bug reports should include all information a person could need to reproduce your problem without the need to
+follow up for more information. If possible, provide detailed steps for us to reproduce it, the expected behaviour and the actual behaviour.
+
+## Feature proposals and requests
+
+Feature requests are welcome and should be discussed in an issue.
+Please keep proposals focused on one thing at a time and be as detailed as possible.
+It is up to you to make a strong point about your proposal and convince us of the merits and the added complexity of this feature.
+
+## Pull requests
+
+Patches, new features and improvements are a great way to help the project. 
+Please keep them focused on one thing and do not include unrelated commits.
+
+All pull requests which alter the behaviour of the program, add new behaviour or somehow alter code in a non-trivial way should **always** include tests.
+
+If you want to contribute a significant pull request (with a non-trivial workload for you) please **ask first**. We do not want you to spend
+a lot of time on something the project's developers might not want to merge into the project.
+
+**IMPORTANT**: By submitting a patch, you agree to allow the project
+owners to license your work under the terms of the [MIT License](LICENSE).