Protocol specifications, authentication mechanics, and the technical details that keep email running.
We recently shipped mailing list support — and what looked like a straightforward feature turned into a deep dive into DKIM signature mechanics and DMARC alignment. This post covers how we built it, the problem we introduced, and how we fixed it.
We’ve upgraded our inbound email defense to stop bad actors before they ever reach your inbox. By focusing on SMTP-level checks, we ensure robust spam protection without ever reading your private messages. Experience a cleaner, safer inbox.
ARC is email's chain-of-custody stamp. When a message is forwarded, ARC proves who handled it and that it arrived intact at every step.