At a high level, at most once delivery pub-sub looks like
We can approximate a nano-discord as a "distributed/multi-machine pub-sub" + "logger" (for message history).
Is there any tutorial on building such a "nano discord" in Rust (or language that easily translates to Rust?). Googling = results on building discord/slack bots.
PS; If you know of a crate with similar functionality, that would be helpful too.