My findings:

> I’ve tested Delta Chat with my own mail server, which uses Postfix and has everything configured for public e-mail, like DKIM signing, spamd, IP blocklist checks and so on, and each message took about 2 seconds from one device to another. Using a public server it sure feels below 300ms, so there is room for improvement when self-hosting a dedicated chatserver.

https://www.kassner.com.br/en/2025/05/08/delta-chat-encrypte...

In my test, both clients were ~80ms away from the IMAP server, but the server was delivering to itself. I’m also not sure if the port 587 has an idle/keepalive mechanism, or if it has to go around the entire TLS handshake at each message.

I don’t think 2 seconds is bad, most of my contacts will take at least triple that to read and type in an answer, so not a big deal.