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CONTRIBUTING.md

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+# Contributing guidelines
+
+**Thanks for considering making contributions to Tendermint!**
+
+Please follow standard github best practices: fork the repo, **branch from the
+tip of develop**, make some commits, test your code changes with `make test`,
+and submit a pull request to develop.
+
+See the [open issues](https://github.com/tendermint/tendermint/issues) for
+things we need help with!
+
+Please make sure to use `gofmt` before every commit - the easiest way to do
+this is have your editor run it for you upon saving a file.
+
+You can read the full guide [on our
+site](https://tendermint.com/docs/guides/contributing).