Haxl: A Big Hammer for Concurrency

Our programming languages are usually "sequential by default", and you have to be explicit if you want concurrency. Much of the code we write, however, is insensitive to reordering, and in these cases concurrency is actually a better default. In this talk I'll describe how the Haxl framework developed and open-sourced by Facebook flips the default from sequential to concurrent. I'll show how that can be useful, and give some insight into how it works.

It turns out that the pieces we need to do concurrency-by-default also help with testing and debugging, which makes Haxl something of a Big Hammer for solving problems involving I/O and concurrency.