[rlander]

Basically anything that is protocol-oriented like WhatsApp. A lot of people will say fault tolerant, low latency, highly available and massively concurrent systems, and they’ll be right, but I think that’s only half the story. You also get a battle-tested blueprint for building these kinds of distributed systems. You will find a pattern here and there in other languages and VMs, but the cohesiveness of the package (language + BEAM + OTP + observability + patterns) is something really unique. Compare this to the Java ecosystem, where there are dozens of concurrency primitives and an even greater number of distributed systems libraries and frameworks like Akka, Mesos, Zookeeper, Storm, Flink, Samza, Heron, Helix...