[schneems]

You got your reply already. To add: YJIT is the one that does "basic block versioning" (Which was Maxime's thesis) while ZJIT is a more traditional design.

I am confident in that description but don't actually know what it means in practice (yes I've seen papers and talks, but I kinda need not-compiler-engineer to explain it to me.)

As I understand it BBV still holds promise, but the sheer volume of knowledge of more traditional methods might mean it gets better outcomes (also IIRC ZJIT is still lagging YJIT).

[maxime_cb]

I gave a talk about ZJIT and the motivation for the change at RubyKaigi 2025 if people are curious. It's on YouTube.

[x0x0]

https://www.youtube.com/watch?v=1CCDuRW0OLk

[schneems]

Thanks for all your work Maxime!

[riffraff]

> IIRC ZJIT is still lagging YJIT

It would be nice to have ZJIT on speed.ruby-lang.org!