tekknolagi

Please feel free to open a PR. I'm a bit AFK

See also https://github.com/nedbat/byterun and https://github.com/rocky/x-python

Damn. I wish I thought of that.

I will add "compiler" before "optimizer" and link to the toy optimizer series

Oh hi! Thanks for posting. As I wrote this I wasn't sure if it was enough of a post. Let me know if you wanted to hear about anything else that seemed missing.

You may enjoy https://github.com/ludocode/onramp

As I said on Lobsters as well, this is a superb overview.

https://bernsteinbear.com

I write about programming languages and compilers

YJIT and ZJIT don't use method annotations.

Yes; see the first ZJIT blog post. https://railsatscale.com/2025-05-14-merge-zjit/

In that scenario, what would you hope to get out of the LBBV?

If all you're doing is summing small integers---frequently the case---it's much preferable to optimize that to be fast and then skip the very dynamic method lookup (the slower, less common case)

YJIT is not deprecated. That word has a specific meaning in Ruby. You can continue to use YJIT.

With any luck, this performance in the next year or two will be enough to make it a happy change. "Damn, free money" etc

Earnestly: why are you annoyed? I tried to make it clear that you don't have to make any changes. If you want, you can try ZJIT (which should not be anything other than a one character change), but you don't have to.

In this case, we used to abort (i.e. abort(); intentionally crash the entire process) but now we jump into the interpreter to handle the dynamic behavior.

If someone writes dynamic ruby code to add two objects, it should succeed in both integer and string cases. The JIT just wants to optimize whatever the common case is.

It's a "teach people how to teach themselves to fish" class

You'll never guess what we talk about later on in the unit. Spoiler: exactly that!

It notionally focuses on make but the concepts apply much more broadly than the one specific tool

The schedule is generated from a Python script, but doesn't involve YAML

If you're interested, see also https://bernsteinbear.com/isdt/ by me and Tom

This kind of compiler/runtime feedback about source code is really interesting and (imo) under-studied. Especially when you take into account something like PGO data.

No, HM is unification based and requires no annotations at all.

sqlitedict? Or shelve/dbm?

The good news is now you got tricked (accidentally, tbh) into reading about compilers!

<3

The real fix felt more complicated when I drafted this. Seems like it isn't; I'll think about updating the post

In case the author didn't notice, the organization name appears to be missing an L - "litte"

Re: ZJIT: all development is happening in the open in the zjit folder of the ruby/ruby repo. You can follow along!

If I may toot my own horn: https://bernsteinbear.com/blog/typed-python/

Excellent subtitle "let's have a tiki". Great joke

I like this. Especially the last paragraph. Mind if I quote you and expand?