If you’re working on patches for Rails, you should sign up for the rails-core mailing list. It’s much more low-traffic than the regular Rails mailing list and designated exclusively for discussions on extending Rails.
So if you have any questions about a patch you’re working on or have completed, this is the place to join. If you have questions of the usage of Rails, announcements, or any of the other jazz, please do keep it on the regular list.