I'm searching for a simple, self-hosted chat system that allows me to host unlimited bots and send messages (with notifications) to my iPhone easily.

I currently have an XMPP server running, which is fine, I guess. I've looked into chatMail. I have considered hosting an IRC server.

At this point, I'm considering just setting up my own NTFY server and writing a chat client for it.

Does anyone have any ideas for what the lightest weight, simplest solution might be?

Curious, why the interest in building your own ntfy client (instead of using the one already built/available)?

By the way, for years now, i have used a little python (cli) app to send messages into a private matrix room. This room has 2 people in it: me and a bot. (The bot is simply the matrix account that sends the messages.) I went this route because i did not want to install another app - such as ntfy - on my mobile simply to receive server notifications, etc. And, since i had ben on matrix already chatting with friends, it happened to be a low-effort approach. To clarify, i am no longer self-hosting my own synapse home server...so i'm simply piggybacking on the matrix.org one...but that has helped at least unify my notifications and comms to a good degree.

Now, if you were to aske me to implement my "notifications system" via a different approach, funny enough, i would gauge between XMPP and ntfy to see which is lighterweight....because i believe them to both be quite light on the need for resources. I don't know which is lighter (sorry, i know i'm not answering your question). however, i *think* the ntfy server is less hasle....Only because xmpp takes a little more work to setup...at least that was my experience a couple of years ago. I cast no shade on either xmpp nor ntfy - because to me boh are awesome...i' m merely saying that resources needs aside, i wonder if ntfy might need less time from YOU.

you should look at celld