Money Forward, Inc. hire Shyouhei, a long-time ruby-core committer, to contribute to the whole ruby ecosystem. Being a full-time ruby-core developer, his current interest is to speed up ruby execution by modifying its internals. Doing so is not straight-forward because of ruby's highly dynamic nature. To tackle this problem he is implementing a variety of optimisation techniques that are yet to be applied to it.
On sending methods
As you have noticed 2.7 is faster than older ruby versions. One of the main reason for this is my optimisation around method invocations. Let me share what was suboptimal, and how was that fixed.