Takashi Kokubun
Takashi Kokubun
  • @k0kubun

Takashi Kokubun is a Staff Developer at Shopify, based in the San Francisco Bay Area. As a Ruby committer, he has worked on JIT compilers for Ruby for 5 years. He optimizes YJIT at work and RJIT in his spare time.

Ruby JIT Hacking Guide

YJIT delivered a significant speedup to various real-world applications. Have you wondered how a Just-In-Time compiler makes your application fast?

Ruby 3.2 has a secret backdoor to hook your own Just-In-Time compiler. Using that “feature”, this talk will guide you through how a Ruby JIT can be written in Ruby. You’ll learn the basics of Ruby VM, how to encode native instructions in Ruby, and interesting optimizations that JIT can do with them.

Presentation Material