Gitter uses a proprietary websocket protocol built on top of the Bayeux protocol: https://docs.cometd.org/current/reference/

More details can be found on the developer site: https://developer.gitter.im/docs/faye-endpoint

We also have an open-source IRC bridge: https://github.com/gitterHQ/irc-bridge

I prefer matterbridge :) Supports more than IRC, and supports multiple gateways at once: https://github.com/42wim/matterbridge/

Depending on the availability of a Bayeux client for Golang, it looks like something that could be integrated quite easily.

I don't know how Gitter support in matterbridge is implemented but it is great! Do try it out. I've been running a three-way discord+gitter+irc gateway for a long time.

And there is a matrix.org/gitter bridge already in use by riot.im

Protocol? I kind of assumed things like Slack, Gitter, etc. were just using websockets that communicate with their backend.

Slack is built on top of IRC. Presumably Gitter is as well

Slack is definitely not built on top of IRC. There is, however, an IRC interface to Slack.

Not on top of IRC. Just similar in that they are both chat like

> Slack is built on top of IRC

Source? First time I hear that, and it seems unlikely, since they have quite a few features that don't fit nicely in stock IRC.

I’m not sure there are any Slack features that don’t fit into stock IRC v3. Basically everything they do is already supported or a draft. (Now just everyone has to implement it)

Now, possibly. But unless I'm totally wrong on the timeline, IRCv3 (not even talking about implementations) wasn't even close to that level when Slack started and thus is unlikely to be the base of their product. And even now, I wouldn't include v3 yet when talking about "stock IRC" in this context.

Any source on that. I don't think it follows any protocols at all. Just implements it's own thing.