Design and Prototypical Implementation of an IRC Chat Server in Erlang OTP | Hacker News Reader

Design and Prototypical Implementation of an IRC Chat Server in Erlang OTP

linuxjournal.com

> On the 4th of October 2021, Meta (former Facebook) and all of its organizations (e.g. Instagram, WhatsApp, Facebook Messenger) were unavailable for up to seven hours. ... This outrage shows that modern solutions must be designed resiliently to enable service provisioning during incidents.... The functional programming language Erlang provides inherent functionality to develop these resilient services.

Ironically, What's App is written in Erlang :)

That being said, it's cool project! I'm not a concurrency expert so people may disagree, but of all the paradigms I've tried, I feel the actor model has the less mental overhead.

IIRC that was a DNS issue, which is why it took down all the Meta services. In other words, the WhatApps Erlang servers were probably happily humming away.

As a famous haiku once said:

It's not DNS

There's no way it's DNS

It was DNS

Although, actually, in this case, it was BGP. The haiku works for both. Now, because (Facebook's) BGP was broken, the DNS servers were unavailable, but WhatsApp will work without DNS (I used to work there, and helped make sure this feature continued during the move to Facebook's infrastructure). Usually, it's your network's DNS that's failing, but sometimes it's WhatsApp's DNS that's failing; either way, having IPs to connect to is sure handy.

Too bad, the diagrams are too tiny and blurry to be of any use. And two of the references at the end are 404. A publicly accessible repository for the prototypical implementation would have been nice.

Strange, is it a re-publishing of an older article?

The date says February 2nd, 2022, and some references are from 2021.

But the component diagram is an old-style UML component diagram, that most of the "Agile/Scrum" devs today will not even understand.

Is there a better version with the readable diagrams?

Curiously enough, one of the exercises in the Programming Erlang book is to write a rudimentary IRC client.

Glad to see both sides now covered :)

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