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+Plan 9 from User Space uses Gerrit instead of GitHub pull requests.
+See the [codereview(1)](http://swtch.com/usr/local/plan9/man/man1/codereview.html) man page.
+
+If you would like to use git directly instead of the codereview(1) wrapper, that is fine too.
+Follow the instructions on the RE2 [Contributing](https://github.com/google/re2/wiki/Contribute) wiki page,
+but use https://plan9port.googlesource.com/plan9 as the origin URL.
+