JMAP – a much needed modern email open standard

I love JMAP. It's what allowed me and my team (at 1Password) to easily add support for Masked Emails, where we randomly generate your email address in addition to your password. Our own Madeline Hanley wrote about that experience, if you'd like to see what it's like to work with JMAP: https://blog.1password.com/making-masked-email-with-jmap/

Unfortunately it includes my biggest gripe about IMAP -- the requirement that messages are given a server-side message number. Maybe breaking with IMAP on this would make interop too hard though. This requirement is convenient for the client but makes implementing robust servers harder than it need be. If instead each message was identified by a {timestamp,UUID} tuple then multiple MX servers could do final delivery to an eventually-consistent shared store. The requirement for strict, durable message ordering is…