[HeXetic]

What do you think they can do with their custom API that IMAP can't? IMAP has server-side search and a file-based representation of things like configuration. It may not be as easy to write as a JSON API, but once you do, the interface is flexible enough to really accomplish anything.

[dewey]

Their whole "filtering everything out until you whitelist the sender" approach which is the one feature that sets HEY apart from the other providers wouldn't really work with normal IMAP.

As for IMAP with more JSON there would also be Fastmails https://jmap.io/

[zimpenfish]

> Their whole "filtering everything out until you whitelist the sender" approach

Unless I'm missing something about what they're doing, this is a basic SIEVE script that filters anything not explicitly whitelisted into a folder.

[HeXetic]

The server can put messages into whatever folders it wants. Different folders can even put the same message into multiple meta-folders. The whitelist can be stored as a message (as basically a file) in a config folder. This is pretty straightforward IMAP.

Again I'm not arguing that IMAP isn't creaky and clumsy but let's not pretend that lack of power is the reason they didn't use it.

[bradly]

Can IMAP snooze messages?

[zimpenfish]

That'd be down to the IMAP server to support, I suspect, but you could certainly have one that understood the logic - "if there's a message in Snoozed and it's older than X, move it to Inbox". If you have access to your mail, you could do it yourself with a shell script and cron.