A major part of my CLAUDE md file is always all of @alexozun.com’s teachings on Type-Driven Design in Swift. It remains, to this day, the most powerful Swift content I’ve ever read. Your agents will output MUCH better code with it. swiftology.io/collections/...

Make the AI agent’s job easy (warning: this may be hard), then give it an easy job.

I initially planned this as a short post on socials, but it quickly evolved into a blog. Here’s my recommended reading list to get you from Zero to Hero in Swift Concurrency. It’s based on my own learning journey, with adjustments that work better for 2026. swiftology.io/articles/swi... #swiftlang

Today at #fosdem #swiftlang in Brussels. Greeted with a perfect swag for a nippy winter day.

Swift Effect is now in public preview! it is an architecture-agnostic effect system that makes side effects (such as I/O, networking, randomness, concurrency) controllable, composable, and testable without forcing structural changes to your application code. github.com/Alex-Ozun/sw... #swiftlang

Dijkstra predicted in 1978 how people would feel about #Swift Strict Concurrency checking in 2025.

Hey friend, I've got a new article on Swift Testing for you! 📝 I share my insights on avoiding common pitfalls of Parameterized Tests, gained from overseeing the migration of tens of thousands of tests from XCTest to Swift Testing. swiftology.io/articles/pit... #swiftlang #swift

Hey look what just dropped! A recording of my recent talk from iOSKonf25! The recording didn't capture the stage camera's feed, but that's totally fine because I have a radio face anyway 🫥 youtu.be/AnUS_zmSnVg #swiftlang #swiftui #ios

Finally got around to watching @alexozun.com‘s talk here. Truly fascinating stuff, and I learned something about non-Copyable types too! youtu.be/qPHjDlqHsUQ?...

RIP Google's #Flutter team who will have to replicate the Liquid Glass look and feel for their Cupertino widgets. #wwdc

This is the second time I’ve seen @alexozun.com’s talk on making invalid state impossible and it’s a really cool approach to improved software safety!

Doug Gregor takes the stage of @swiftcraft.bsky.social with a keynote talk On Progressive Disclosure in #swiftlang

I had a blast presenting at #iOSKonf25 this week! I heard great things about this conference and I now can say that the praise was well-deserved! It was pretty scary to be on the lineup with so many accomplished engineers and speakers, but the vibe was really good and everyone was easy to be around.

Next up: @alexozun.com on how to make invalid states impossible in your app.

The secret to introducing people to scary-sounding concepts like Free Monads in #swiftlang is in never mentioning these two words until the very end of the presentation.

Tiers of Swift development sins by Pietro Messineo at @swiftheroes.bsky.social

Good software design is about adding the necessary amount of indirection without compromising performance too much.
Good performance optimization is about removing unnecessary indirection without compromising software design too much.

Now, that it's official, I'm sharing my 2025 #swiftlang conference schedule, so far: 1. Swift Heroes (April 8-9): Controlling Side Effects with Swift. 2. iOSKonf (May 13-15): Make invalid state impossible in your apps. 3. Swift Craft (May 20-21): Swift Abstractions Demystified.

Feedback like this is what keeps me going (even at my snail's pace 😅)

My 2025 #swiftlang conference schedule is shaping up 🗓️ This year, I'm bringing not one, not two, but *three* brand new talks to the community! So far, these are confirmed: 1. Controlling side effects with Swift 2. Make invalid states impossible in your app 3. Swift abstractions demystified

Caffeinated and ready to learn how to build fast and efficient apps from #Apple engineers at the new Dev Center in Battersea Power Plant.

I've been putting off reading #brandonsanderson books for a few years, but finally got to them. Now that I've finished the Mistborn trilogy and started the Stormlight Archive, he's quickly becoming my favourite modern fantasy author - on par with Sapkowski (while having a more pleasant personality).

It's great to see #Apple bringing these in-person sessions to local dev centers around the world. I look forward to hearing about "Building faster and more efficient apps" in two weeks.

My talk from Swift Heroes 2024 has just been published. If you're interested in Noncopyable types, type-level programming, and State Machines, check it out. I had a lot of fun researching Typestate programming in #swiftlang, and I'm happy with how this talk turned out. youtu.be/qPHjDlqHsUQ

I'm a weird type of an application developer because when it comes to customer support I absolutely hate any sort of automation or self-service like chat bots or phone robots. If I'm performing a BAU operation, like changing a PIN number, I just want a button that's directly hooked up to API.

It was nice visiting #apple developer center in Singapore the other day

Yes, they really flew me all the way from London to Singapore just so I could show a photo of an elephant to #iosconfsg audience.

Heading out to my first conference of the year at #iOSConfSG If you happen to be around, drop me a message and let's have a coffee ☕️ P.S. I prefer to travel light and only pack essentials.

Holy smokes🤯! I think I was just able to create a proof-of-concept of #swiftlang effect system that allows to write direct style imperative code and then test it WITHOUT mocks by stepping through each suspension point and directly feeding input arguments to effects (e.g. readline).

I'm having a "do I even know Swift?" moment. I understand that #swiftlang generics are invariant, i.e. F<Dog> is not a subtype of F<Animal>, even though Dog is a subtype of Animal. But some stdlib generic types like Optional and Array do track subtyping (see pic), while others, like Result, don't.

I like this Onboarding UX from Mozi where each step reveals a new tab on the tab bar #ios #ux

A/B testing is one of the most overused and misused engineering techniques ever. And what's worse, the majority of dev teams are pretty oblivious to the immense complexity even the simplest A/B test brings to their mobile systems. It's crazy how we got here. youtu.be/cTbTZ-uShr8 #ios #swiftlang

A procrastinating conference speaker's equivalent of an indie dev "spending an entire day designing the app icon before writing a single line of code" is "spending an entire day designing the title slide before adding any content." And I'll redo the title slide 15 mins before the talk anyhow. Twice

With #swiftlang It's easy to forget that the diff between a point-free and pointed styles of function argument passing is not just syntactic but semantic. It's normal to consider these to be equivalent: 1. [1, 2].map(String.init) 2. [1, 2].map { String($0) } But we shouldn't forget that: 1/4

Loving this "unlock, generously" paywall option 😁

Honestly, craftinginterpreters.com is the funniest technical book I read in a while. @munificent.bsky.social writing style is 😙🤌

A problematic little #swiftlang pattern I often see is "unwrap-then-nullify" for optional values that hold some temp state. This oft comes up when dealing with local caches or scrollOffsets or in-flight tasks, etc. Forgetting to nullify a value to "reset" state is a common mistake. Use take method.

This might be my favorite new warning in #Xcode 16! I totally missed SE-0364, so it was a pleasant surprise to see that #swiftlang compiler nows warn about potentially conflicting protocol conformances. This is super helpful for any highly-modularized project (aka freaking all of them these days!).

It's my annual learning week at Amex, and I'm building a small programming language using #swiftlang, following a fantastic book craftinginterpreters.com by @munificent.bsky.social Super pumped about this challenge, I already know I'm gonna have a great time!

Semi-accidentally found Slava Pestov's book "Compiling Swift Generics". It looks demanding, but def not as dense as a typical compilers textbook. And being based on #swiftlang, the lang I more/less know, gives me some hope. This might be my next big reading project download.swift.org/docs/assets/...

Last week, our #iOS engineering team at #amex in London had the privilege of hosting a #SwiftUI Workshop by the highly regarded objc.io team, @chriseidhof.bsky.social and Florian Kugler.

Good read! Though, some points went over my head since I haven't had a chance to dig deep into Swift 6. I'll take another pass, but here are my immediate thoughts:

Blue sky is literally on our flag! 🇺🇦 Ukrainian #swiftlang programmers, join this starter pack to quickly connect.

Dunno how this information evaded me this long, but I learned from @chriseidhof.bsky.social the other day that you can interact with backgrounded apps without bringing them to foreground by CMD-clicking. My life will never be the same. #macOS #mac

Ok, this looks like a must-read with my tomorrow's morning ☕️ github.com/hborla/swift... #swiftlang

We’ve covered countless topics on Point-Free, but this year’s deep dive into Equatable/Hashable was a standout favorite of our viewers. Master these protocols and learn why classes should (almost) never conform based on the data they hold. 😳 www.pointfree.co/blog/posts/1...

So #bluesky has Starter Packs. What about Starter Packs of Starter Packs? A Higher-Order Starter Pack, if you will?

Had a great time at @nslondon.com event at #Apple shiny new office at Battersea Power Station. The first photo is mine, but the second is from the internet, the security people looked way too intimidating for me to break the no-photo rule 👮‍♂️ Great talks by @oliverbinns.co.uk and @beccais.online

Feedback like this is what keeps me going ☺️

Maybe a nitpick, but I dislike that Swift Testing snippet defaults to `async throws` test. I prefer starting with the most restrictive type and extend it as needed. I only noticed half my tests were needlessly async throwing hours later, bc the compiler was silent. #swiftlang #swifttesting #xcode