This is a simple guide to install new Ruby 3.2.0 with YJIT Compiler.

Note: if you want to read more about JIT Compilers, read this overview

First, you need to have asdf ready on your Mac. I migrated to this tool and it manages all my languages, like: ruby, python, node, rust, etc.

I recommend updating the asdf to the latest version:
brew upgrade asdf

In order to build ruby with YJIT, you need to install rustc.

asdf plugin-add rust
asdf install rust latest
asdf global rust latest

Verify it is installed correctly: rustc --version

Now you are ready to install Ruby:

export RUBY_CONFIGURE_OPTS=--enable-yjit
asdf install ruby 3.2.0
asdf global ruby 3.2.0

Check your ruby: ruby --yjit -v

And you should see YJIT enabled.

Enjoy your speed!