+ TESTING openarc.org provides infrastructure you may use to get familar with ARC. ++ 1. Autoresponder Send a message to email@example.com. You'll receive a response seconds later. This response contain the message as received by the service. This allowes you to inspect how !OpenARC validate your sent message. ++ 2. Forwarder Send a message to firstname.lastname@example.org. You'll receive your message //forwarded// back to you seconds later. It's not a new one. Existing DKIM signatures are expected to be still intact after forwarding. But you may force message modification to invalidate your existing DKIM signature: Choose the text "modify" as Subject and it will be prepended with "[MODIFIED]: " on forwarding. Your DKIM signature will be no longer valid. We assume you sign the RFC5322.Subject header as advised by [https://tools.ietf.org/html/rfc6376#section-5.4 RFC 6376 - DKIM Signatures] ++ 3. Mailing-List [mailto:email@example.com Subscribe] to the
mailing-list firstname.lastname@example.org. Then you may send messages to email@example.com. As usual your message is resend to all subscriber. There is no public list archive as that donsn't make sense.