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CONTRIBUTING.md

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+# Contributing to Feather
+
+Feather is an ambitious project, and contributions are always welcome!
+
+If you want to work on the codebase, please keep the following in mind:
+* Run `rustfmt` on your code before committing. The CI build will fail if rustfmt detects formatting errors.
+* Run [`clippy`](https://github.com/rust-lang/rust-clippy) on your code and fix any warnings it gives. Clippy can detect common mistakes, and as with formatting, the build will fail if there are Clippy warnings.
+* Where possible and necessary, please write tests.
+* Run `cargo test` before committing to ensure you have not broken anything.
+
+Also, please do not write code that is in any way inspired, based on, or taken from Mojang's work, including but not limited to
+the vanilla server and client. Feather is a "clean-room" implementation, meaning that it is written
+from scratch without any involvement with proprietary code. By using code from Mojang, the project
+would become prone to legal issues.