In the Ruby 3 features, a lot of attention went to Ractors - a new parallelism primitive which provides what can best be described as “Web Workers” - separate threads of execution with memory isolation from the spawning thread. However, there was also a release of a seemingly “nerdy” feature which is the FiberScheduler. Ractors still have to prove their own (my dear friend Kir Shatrov has done some exploration into designing a Ractor-based web server) but I would like to highlight that second feature, and the concept of scheduling and reduction in general. I strongly believe making good use of Fibers is instrumental to Ruby staying relevant for creating web applications. As a community we are in a tight squeeze now, between Go on one side and Node.js on the other side, and the concurrency story in Ruby isn’t that good compared to either of the two - however we stand a measurable, substantial chance of once more getting ahead of the game. Especially considering that Python3 has chosen for the “colored” functions…