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CONTRIBUTING.md

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+# Contributing to Bazel
+
+## Contributor License Agreement
+
+Contributions to this project must be accompanied by a Contributor License
+Agreement. You (or your employer) retain the copyright to your contribution,
+this simply gives us permission to use and redistribute your contributions as
+part of the project. Head over to <https://cla.developers.google.com/> to see
+your current agreements on file or to sign a new one.
+
+You generally only need to submit a CLA once, so if you've already submitted one
+(even if it was for a different project), you probably don't need to do it
+again.
+
+## Patch Acceptance Process
+
+The process is described in the [README for this repository](README.md). For
+background, you should also understand how to
+[contribute to Bazel](https://bazel.build/contributing.html).
+
+## Setting up your development environment
+
+Read how to
+[set up your development environment](https://bazel.build/contributing.html).