ejabberd VS Prosody IM

XMPP server using Prosody

lua on its own right can be fun too! If you are looking for a project to contribute to, there's for instance the Prosody XMPP server that's written in it, and contributes to the betterment of internet by promoting federated protocols.

There's also the http://prosody.im/ XMPP server that's written in Lua, and it's very successful there. The other major XMPP server implementation is in Erlang and they are equally praised, so that should tell something about Lua's versatility.

Take your pick. Or just look here.

You can write largish standalone application in Lua and it is not always a poor choice - Prosody [1] first comes to mind. But qualities which make it a good embedded language make it less _attractive_ for other uses.

Lua has very simple syntax and small stdlib which allows its implementation to be very small - you can add Lua to your application and not increase its size significantly. But when the size is not a concern most programmers prefer languages with rich, powerful syntax lots of features and batteries-included stdlib (which is completely opposite of Lua).

[1] https://prosody.im/

If you are really set on a LAN-only setup you could look at Prosody (combined with an Android app such as Conversations) which Snikket is based upon. It's not as "ready to go, out of the box" as Snikket and therefore requires a slightly higher skill level, but in exchange it is a lot more customizable and adaptable to different kinds of deployment scenarios.

Selfhosting XMPP is pretty simple with https://prosody.im/

My choice, because it's the stack I know very well, would be Prosody ( https://prosody.im/ - I'm one of the devs) and a web client such as Converse.js ( https://conversejs.org/ ). XMPP is highly extensible, Prosody is highly modular, which make them a good foundation for building on top of.

That said, the right stack is generally the one that matches your requirements, and (if this isn't primarily a learning exercise) whatever you're most familiar with. The hardest part of building a Discord or Slack-like in 2022 is actually not the technical stuff. There are many comprehensive open-source products already out there that compete with these companies, such as Mattermost, RocketChat and Element.