Erlang's not about lightweight processes and message passing

Summary

Erlang’s not about lightweight processes and message passing… Table of contents Posted on Jan 18, 2023 I used to think that the big idea of Erlang is its lightweight processes and message passing. Over the last couple of years I’ve realised that there’s a bigger insight to be had, and in this post I’d like to share it with you. Erlang has an interesting history. If I understand things correctly, it started off as a Prolog library for building reliable distributed systems, morphed into a Prolog dialect, before finally becoming a language in its own right. The goal seemed to have always been to solve the problem of building reliable distributed systems. It was developed at Ericsson and used to program their telephone switches. This was sometime in the 80s and 90s, before internet use become widespread. I suppose they were already dealing with “internet scale” traffic, i.e. hundreds of millions of users, with stricter SLAs than most internet services provide today. So in a sense they were ahead of their time. In 1998 Ericsson decided to ban all use of Erlang. The people responsible for developing it argued that if they were going to ban it, then they might as well open source it. Which Ericsson did and shortly after most of the team that created Erlang quit and started their own company. One of these people was Joe Armstrong, which also was one of the main people behind the design and implementation of Erlang. The company was called Bluetail and they got bought up a couple of times but in the end Joe got fired in 2002. Shortly after, still in 2002, Joe starts writing his PhD thesis at the Swedish Institute of Computer Science (SICS). Joe was born 1950, so he was probably 52 years old at this point. The topic of the thesis is Making reliable distributed systems in the presence of software errors and it was finished the year after in 2003. It’s quite an unusual thesis in many ways. For starters, most theses are written by people in their twenties with zero experience of ...