4 HN users recommended this demo4 months2013–2026score 4.5
Years with an HN recommendation, 2007–2026
A beloved classic that HN recommends as the quickest way to see why Erlang is special.
A short Ericsson film demoing Erlang, showing concurrent processes, debugging tools, and hot code reloading, including crashing parts of a running system while calls continue.
“the designers of Erlang demo some of the qualities of the Erlang system in a delightful way” (HN, 2017)
And if you haven't seen it, here is some classic. “Erlang: the Movie”: — [this video] And sequel “Erlang: the Movie II”: — [link] Don't think wtf. Just watch.
The author doesn't talk a lot about preemptive scheduling, which is probably the best thing about the Erlang virtual machine. This video explains what preemptive scheduling is and why it is extremely useful: [link] First, the speaker creates an application endpoint that runs into an infinite loop on invalid input. Then, he shows how that doesn't block the rest of the requests. Using native BEAM (EDIT: BEAM = EVM = Erlang Virtual Machine) tools, he looks for the misbehaving process (the one running the infinite loop), prints some debug information and kills it. It's pretty impressive. Another great (and lighter) resource, is "Erlang the Movie" ( [this video] ). It shows the power of concurrency through independent processes, the default debug tools, and the power of hot code reloading. Don't miss the twist at the end.
Shows concurrency, debug tools and hot code reloading
It is one of the core features of Erlang (a language developed by Ericsson), being able to rewrite code in production, with errors/crashes that break one thread not affecting another. Obligatory link to Erlang: The Movie (10min)- [this video] Note that they start crashing things in Erlang around minute 7, and fix them shortly thereafter. Meanwhile, their setup keeps calls that weren't directly involved in the crash alive and running unaffected.
Crashes things at minute 7 while calls keep running
I discovered Erlang in the late 2000s via its kinda weird and iconic video "Erlang the Movie" [this video] that prompted me to dig further. I was at the time an average developer. Erlang, and Joe Armstrong books and videos, made me understand things that other web-oriented languages ( Ruby, PHP... ) never really dug into at the time. Because the Erlang ecosystem is more than distribution. Distribution is a consequence of its design around concurrency and message passing and let-it-crash/auto-healing philosophy. Erlang, and after that Elixir, made me think differently about code and made me a better programmer.
The video that prompted the commenter to learn Erlang
It isn't entirely true though. The original Erlang guys made Erlang: The Movie [this video] and the sadly missed Joe Armstong made plenty of blog posts [link] and public appearances and expressed a number of strong opinions (though genially) [link] . Robert Virding's public profile is not as high, but he's by no means in hiding either. [link] — or indeed [link] )
> Clojure Alex Miller and Stuart Halloway immediately jump to mind as lieutenants that could jump in and take over without too much disruption. > Erlang Well, there's also Roberts and Mike (reference, for those not familiar: [this video] ).
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