Curious the direction of Webkit as there was a nebulous mention of select portions being rewritten from C++ to Swift. And yet, the new ECMAScript module (ESM) loader for Safari 27 is implemented in C++ (https://webkit.org/blog/17967/news-from-wwdc26-webkit-in-saf...).
These days I mainly write Rust but I did write a semi complex iOS app and enjoyed Swift. I just didn't love how slow the type checker was and how it got lost. I recall having to break things into smaller bits to help the compiler, and there were some oddities about the language.
The gap between the two languages is quite small, it just makes me wish Apple was also all-in on Rust
Some corporations prefer Apache 2.0 for projects where they'll be accepting contributions, because it includes patent protection and retaliation clauses. In case like this, where source code is just being published for reference and contributions aren't accepted, those risks don't exist.
Given the age of TrueType, wouldn't nearly all patents be expired already?
Apache2's license I've heard described as mutually-assured-patent-destruction - if you use the code and make a patent claim, your rights to use the code go away.
So Apache2 offers little benefit here, and MIT may get it into more hands?
Russinovitch (Azure's CTO/CISO) gave a speech at RustConf 2025 and mentions it(DirectWriteCore) took 2 engineers 6 months resulting in 154K LOC and 5-15 percent performance increase for font shaping. https://www.youtube.com/watch?v=uDtMuS7BExE&list=PL2b0df3jKK...
What's funny is from 2023 (I think), macOS just draws the UI unhinted. You have a 1080p display and you don't want to see the letters in the UI blurred to death? Tough luck, 1080p is incompatible with macOS, everybody needs "retina", and nobody cares that Windows and all Linux DEs look on 1080p just fine.
It looks like this hinter will be used only in rendering PDFs, because that's where they test the performance.
I'm surprised the code has visible LLM smells. Though, I shouldn't be surprised. I hope the important bits are still human-controlled (and the same for Apple's many operating systems that absolutely deserve to remain stable and understood).
It would be interesting to see their internal guidance on LLM use. It’s a massive amount of new power that has to be wielded carefully. That kind of guidance might mean the survival or downfall of some big corps in the next few years.
I think these are the types of things Apple should've focused on instead of half-heartedly barging ahead with SwiftUI and breaking the language in the process
There's mention at the end. The models (and Swift itself!) have evolved a lot since this project started, so the early code is largely hand-rolled and the later changes were mostly authored by centaurs (to steal a term from chess).
But I personally reviewed every line that shipped and was absolutely insufferable about testing.
RIS is happening across all OS levels, if the keynote is to be believed.
In any case I would have liked to have more info during the deep dive sessions.
As it is, Meet with Apple on security (a 5h long event) had much more information.
https://faultlore.com/blah/swift-abi/ (written by a core Rust developer)
[1] apart from the basic/universal C one, which prevents exposing any useful Rust semantics over the interface
The gap between the two languages is quite small, it just makes me wish Apple was also all-in on Rust
Apache2's license I've heard described as mutually-assured-patent-destruction - if you use the code and make a patent claim, your rights to use the code go away.
So Apache2 offers little benefit here, and MIT may get it into more hands?
I'm not sure what became of it and if it ever shipped. If anyone knows I'd be curious.
https://xoxo.zone/@numist/116716469017975106
It looks like this hinter will be used only in rendering PDFs, because that's where they test the performance.
It worries me. I hope Codex adoption picks up there.
But I personally reviewed every line that shipped and was absolutely insufferable about testing.