contrapunctus

The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair.

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Jabber, a.k.a. XMPP. It's decentralized, featureful, standardized, and low on server resources.

Here's a user's guide I wrote.

https://contrapunctus.codeberg.page/the-quick-and-easy-guide-to-xmpp.html