Twitter's page seems reasonably simple and straightforward, use that.
diff --git a/README b/README
index 5a4a2ca..5fc9ec0 100644
--- a/README
+++ b/README
@@ -130,3 +130,8 @@
 
     video: http://elinux.org/ELC_2015_Presentations
     outline: http://landley.net/talks/celf-2015.txt
+
+--- Code of conduct
+
+We're using twitter's https://engineering.twitter.com/opensource/code-of-conduct
+except email rob@landley.net with complaints.