If you want to help improve the security of OS software through the magic of memory safe languages, the team that did this work is hiring: <a href="https://jobs.apple.com/en-us/search?search=Spear&sort=relevance&location=united-states-USA" rel="nofollow">https://jobs.apple.com/en-us/search?search=Spear&sort=releva...</a><p>Knowledge of Swift not required. If you know your way around OS software, can reason about the security of the code you write, and are excited about writing exhaustively tested software, we’d love to talk to you.<p>We’re hiring for roles in kernel/systems and userspace. Like the Platforms SOTU mentioned, we’re using Swift at all layers of the software stack now. <a href="https://www.youtube.com/live/yl2jsIoMfDU" rel="nofollow">https://www.youtube.com/live/yl2jsIoMfDU</a><p>I had the pleasure of leading the effort to ship Swift in the Secure Enclave back in 2022. Now I have multiple teams working on accelerating the transition to memory safe languages. We’re showing that with good planning and a relentless focus on testing, we can improve security, performance, and functionality. And we get to have a ton of fun working with some amazing colleagues. It’s the most enjoyable and impactful work I’ve ever done in my career.
Beware: As of a few months ago, when I tried to use the lifetime features shown off in this post, I ran into constant compiler crashes with very simple programs, until I gave up and wrote off the features as unusable. This happened on both stable and nightly compilers. I guess they work well enough for this TrueType interpreter, but I suspect they’re using a narrow subset of what the features are supposed to support. Or maybe things have been fixed very recently.<p>That said, I’m looking forward to using Swift lifetimes once they actually work!
During the State of Platform keynote, on the subject of Swift adoption across macOS, several examples were given, not only TrueType engine.<p>RIS is happening across all OS levels, if the keynote is to be believed.
They’ve been doing it for years. I don’t remember how we first knew, but I know they’ve been using Swift in kernels for at least some of the other chips like the Secure Enclave or whatever.<p>I’m not sure exactly which. I assume it’s some of the code and not all. But it’s not new in the abstract.<p>That said I don’t think I’ve heard of it in the kernel of MacOS on the main processor. That may be new.<p>Either way this is certainly the most concrete announcement I remember them ever giving on this stuff.
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++ (<a href="https://webkit.org/blog/17967/news-from-wwdc26-webkit-in-safari-27-beta/" rel="nofollow">https://webkit.org/blog/17967/news-from-wwdc26-webkit-in-saf...</a>).
No idea, maybe the private parts of the code, Safari isn't open source, or is coming later.<p>In any case I would have liked to have more info during the deep dive sessions.<p>As it is, Meet with Apple on security (a 5h long event) had much more information.
What does RIS stand for?
The author discussed this a bit on Mastodon as well:<p><a href="https://xoxo.zone/@numist/116716469017975106" rel="nofollow">https://xoxo.zone/@numist/116716469017975106</a>
Interesting that this is published under the MIT, rather than Apple’s more favorite Apache 2, license
Back in 2023 there was talks about Microsoft rewriting the font stuff in Rust for similar reasons Apple is now doing the Swift move.<p>I'm not sure what became of it and if it ever shipped. If anyone knows I'd be curious.
So, hinting only takes place at low resolutions, I believe. How often is it used, eg viewing “typical” PDFs on “typical” screens?
As much as I enjoyed Swift, one can only wonder what the world would look like if they had gone with Rust as their default language instead.
Rust doesn't have an ABI [1]. Swift needed one to be a useable application language:<p><a href="https://faultlore.com/blah/swift-abi/" rel="nofollow">https://faultlore.com/blah/swift-abi/</a> (written by a core Rust developer)<p>[1] apart from the basic/universal C one, which prevents exposing any useful Rust semantics over the interface
One of the genius things about Swift is its interop with Objective C. Made the switch over considerably easier for developers. I’m not sure what that looks like in a Rust world.<p>Rust is also just a more complex language. I’m not convinced the benefits would have been worth it.
Not just interoperability with Objective C but with C (full) and C++ (increasingly better but not full) as well.<p>Swift is also interoperable with different versions of itself courtesy of the Swift stable ABI (Application Binary Interface)[0], which they invested a significant amount of time into at the expense of adding other new features to the language, which have come along later.<p>Rust offers a different approach: recompile everything and static linking.<p>[0] <a href="https://faultlore.com/blah/swift-abi/" rel="nofollow">https://faultlore.com/blah/swift-abi/</a>
Modern Swift borrows a lot from Rust! And it also has its own benefits, both ergonomic and also supporting eg generic in dynamic libraries
Swift and Rust were developed at similar times. I think of them more as having similar influences than borrowing from each other.
There’s no reason to invent your own head canon, the influence was openly acknowledged when Swift was new and it continues now that the language is developed out in the open (see Swift Ownership Manifesto)
Similar times and the Rust originator went on to work on Swift after it.
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.<p>The gap between the two languages is quite small, it just makes me wish Apple was also all-in on Rust
In the last year they’ve added improvements to the type checker to speed it up, those would have been released now.<p>They have further and much more significant changes that I think might have recently landed in the development version. That should make an even bigger difference. But it’s not in a released version yet.<p>And yes, none of us like that one part of Swift. Especially the DRASTIC difference compared to objective-C which really only checked syntax and little else.<p>It’s still probably my favorite language right now though I don’t get to write in it much.
I see Swift as a more approachable version of Rust.<p>If somebody is mulling over Rust but finds it too difficult to grasp, they could start off with Swift first and then move over to Rust.<p>One of the main advantages of Rust is a more developed and thriving ecosystem.
maybe so on the surface, but it remains quite massive underneath; these languages are fundamentally different and target entirely different use cases
I'm not sure Rust has one specific use case as its main goal, despite being immediately suitable for systems programming.<p>I use it for making user-facing desktop applications, to name one example.
Does it borrow borrow checker?
I believe Swift tends to use reference counting and copy-on-write strategies. This, like GC, is less for the programmer to think about and doesn't require the semantic checks, but sometimes the performance cost is unacceptable compared to what you'd write in Rust.
You can choose to use either refcounting or unique ownership for your types. For most use cases, refcounted (+ copy-on-write) is the best choice and is the default, but the truetype interpreter made extensive use of non-refcounted types to achieve this performance.
They have either recently added or talked about a borrow style system in the language as a way to avoid more copies and speed things up/lower memory usage/help with asynchronous programming.
Yes, it has a borrow checker.
Welcome to the club of doing high performance text in a memory safe language!
There are dozens of us! Dozens!<p>Vello has been a big inspiration and source of knowledge for my own webgpu text renderer, thank you for that!
> high performance text<p>Just strings or <i>rendering</i> strings?<p>If the latter, who are the other members of the club?
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).
I assure you, every inch of the interpreter code has been stared at by humans, a lot. TBH even the assembly generated by it has.
From what I got Apple is using claude code A LOT internally
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.
Yes they are using Claude Code - not the Xcode agents.<p>It worries me. I hope Codex adoption picks up there.
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.<p>It looks like this hinter will be used only in rendering PDFs, because that's where they test the performance.
While hinting is disabled for most fonts, there are some fonts that require hinting to render correctly. We have to support hinting for those fonts, and it was easier to make it secure by rewriting hinting in Swift than it would have been to comprehensively identify every font created by those foundries.
My last 1080p monitor was around 20 years ago. I have trouble comprehending people still use them regularly.
Then let me blow your mind:) One of my daily drivers is an ex-Chromebook at 1366x768. Granted, it's also physically smallish so the DPI isn't <i>quite</i> as low as a macbook would be with those pixels, but still. And that's a touch cramped but it's fine.
A very quick search yielded Dell selling 1080p laptops today:<p><a href="https://www.dell.com/en-us/shop/dell-laptops/dell-15-laptop/spd/dell-dc15250-laptop" rel="nofollow">https://www.dell.com/en-us/shop/dell-laptops/dell-15-laptop/...</a><p>It is very, very common. Just not in the Mac world.
It’s very common for the people who got their last monitor 8 years ago.
It's still the most common resolution for people using desktop monitors today, according to: <a href="https://gs.statcounter.com/screen-resolution-stats/desktop/worldwide" rel="nofollow">https://gs.statcounter.com/screen-resolution-stats/desktop/w...</a>
It's also the corporate standard for generic cubicle workstation monitors, though it's unusual to find a Mac in such a place anyway.
People also use usable mice instead of touchpads, and they put the "ctrl" key where Apple thinks a useless "fn" should be. All kinds of things happen outside Apple world.<p>To me, it's more about what I'm used to. I have a perfectly fine several years-old monitor, so why should I throw it away?
The problem is, as soon as you are not on a Mac but Linux or Windows, you are in for an awful, truly awful lot of pain. HiDPI support is a mess because even in the rare case applications are made with HiDPI in mind they are not <i>tested</i> on HiDPI machines.<p>Other way around, most Mac software is not tested how it behaves on inferior external monitors.
macOS has been drawing unhinted text for an eternity, and for those who can tolerate it on low-DPI screens, it's a great thing: the letter shapes look the same at all sizes, and the spacing between letters is consistent at all sizes.
I'm a high DPI snob so I haven't used a low res monitor for work in forever, but isn't the entire point of font hinting to make the text more legible at smaller pixel grid sizes? Yes, of course the shapes are more consistent since the hinter isn't touching them, but isn't the end result just less legible text?
I had this problem on the first Apple Silicon Mac Mini in 2020 so it's at least a little older than 2023.
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
No mention of AI? Hand written code?
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).<p>But I personally reviewed every line that shipped and was absolutely insufferable about testing.