[HalcyonicStorm]

Erlang is uniquely suited to chat systems out of the box in a way that most other ecosystems aren't. Lightweight green threads via the BEAM vm, process scheduler so concurrent out of the box, immutable data structures, message passing as communication between processes.

[nradov]

There's nothing unique about Erlang. I have nothing against it but other companies have built messaging systems using other platforms that work as well or better than WhatsApp.

[aiisjustanif]

Examples please.