Johannes Weiss
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jweiss.io
Johannes Weiss
@jweiss.io
Computer programmer (http://github.com/weissi). Distributed systems, ML infrastructure/eval, Swift, previously #SwiftNIO — ♥ snowboarding

London, UK
Cat's marketing department is ... something. Seems like they're making gas turbines in a facility they call "Solar Turbines". Under the Oil & Gas category, of course.
November 6, 2025 at 7:48 AM
Reposted by Johannes Weiss
Observability is the key to understanding how your system performs and where problems are occurring. Moritz Lang and Si Beaumont gives us the run down on how it works in Swift!

www.youtube.com/watch?v=HSxI...
Observability in Server-Side Swift - Si Beaumont & Moritz Lang
🎥 Recorded at the ServerSide.swift conference in London in 2025. 🙌 Sponsored by Broken Hands: https://www.brokenhands.io 🐥 Twitter: https://twitter.com/swiftserverconf 🐘 Mastodon:…
www.youtube.com
November 5, 2025 at 4:02 PM
Reposted by Johannes Weiss
A post from @joannis on the #Swift blog about the new preview of the Android SDK for Swift

www.swift.org/blog/nightly...
Announcing the Swift SDK for Android
Swift has matured significantly over the past decade — extending from cloud services to Windows applications, browser apps, and microcontrollers. Swift powers apps and services of all kinds, and thank...
www.swift.org
October 24, 2025 at 9:33 PM
Made a little thing that may help you profile your services from within their own process -- no extra privileges or tools required.
New tooling for profiling performance-critical services with Swift -- introducing the Swift Profile Recorder. More here: www.swift.org/blog/swift-p...
October 6, 2025 at 7:24 PM
Isn't that too beautiful? PM2.5 of an overnight pyrolytic oven clean starting at 1am.

Still woke up at 3am on account of bad air, despite closed doors and open windows in kitchen...
October 6, 2025 at 6:37 AM
Reposted by Johannes Weiss
It's been an incredible year for the conference. We had attendees from 6(!) continents come together for an amazing 3 days of workshops, talks and meeting each other face to face. Thank you to all the volunteers and speakers, it's been truly special
October 3, 2025 at 9:30 PM
Reposted by Johannes Weiss
The new Swift configuration API makes the most of Swift's type checking and expressivity to make it eady to solve common config tasks. @czechboy0.dev walks us through its features @serversideswift.info

forums.swift.org/t/introducin...
October 3, 2025 at 3:29 PM
Reposted by Johannes Weiss
2025 - that's a wrap

#swiftlang
#serversideswift2025
October 3, 2025 at 4:30 PM
Reposted by Johannes Weiss
If a team that lived in C and Go can build production container infrastructure in Swift, the language is ready for serious server-side systems work. - Eric Ernst, Apple #swiftlang #serversideSwift2025

github.com/apple/contai...
GitHub - apple/container: A tool for creating and running Linux containers using lightweight virtual machines on a Mac. It is written in Swift, and optimized for Apple silicon.
A tool for creating and running Linux containers using lightweight virtual machines on a Mac. It is written in Swift, and optimized for Apple silicon. - GitHub - apple/container: A tool for creati...
github.com
October 3, 2025 at 4:03 PM
#ServerSideSwift was so great. Fantastic to (re)connect with people from literally all over the world.

Loved the very positive energy and the buzz around all the new stuff & maturity refinements around the existing tech.

Most importantly thank you @0xtim for putting up this amazing show again!
October 4, 2025 at 10:17 AM
Dropped my last coffee beans on the floor this morning. Was desperate enough that I picked them all up and made a coffee. Guess it's 99% arabica & 1% random dirt 🙈
September 26, 2025 at 7:33 AM
Reposted by Johannes Weiss
Reposted by Johannes Weiss
The conference has always been about bringing the community together and growing Swift on the server. So to help, we're dropping the price of the beginner workshop to just £25! This workshop from Apple will teach you everything you need to get going!

Tickets - www.serversideswift.info/tickets/
September 21, 2025 at 11:00 PM
Reposted by Johannes Weiss
Swift 6.2 is here, including so much 🆕🥳:
⏩Approachable concurrency
🦺Opt-in strict memory safety
📦WebAssembly support
🏃Faster build perf for macros
🐞Enhanced async debugging
📚Inline stack-based arrays
🚇Subprocess support
🧪Test result attachments
www.swift.org/blog/swift-6...
Swift 6.2 Released
We’re excited to announce Swift 6.2, a release aimed at making every Swift developer more productive, regardless of where or how you write code. From improved tooling and libraries to enhancements in ...
www.swift.org
September 16, 2025 at 5:29 PM
Reposted by Johannes Weiss
With ✨Swift 6.2 ✨, you can now target WebAssembly, including WASI support. Get started here: www.swift.org/documentatio... #Wasm
September 17, 2025 at 7:36 PM
Who else is going to #ServerSideSwift? Two weeks to go, can't wait to hear what y'all have been up to!

To make the deal even sweeter, I hear there's tasty 15% off discount code for www.serversideswift.info/tickets/: COMMUNITY15
Tickets | ServerSide.swift Conference
ServerSide.swift - the conference for server-side Swift developers
www.serversideswift.info
September 16, 2025 at 4:22 PM
Yup! I confused a lot of people when I used the UK version in a meeting a few months ago 😛
It’s very confusing that “to table something” has the opposite meaning in the US and UK. 😵‍💫
September 11, 2025 at 6:18 AM
🤩
When it comes to seamlessly integrating the bike and train, proximity of parking to the platform is everything, with Dutch railways dictating the walk not exceed four minutes. Which is why Tilburg Station has built two bike parking facilities totalling 7,500 spaces—one on either side of the tracks.🧵
September 5, 2025 at 8:18 AM
Reposted by Johannes Weiss
Wow. Check this out.
Politicians actually trying to solve problems can achieve a lot!
www.washingtonpost.com/climate-solu...
Paris said au revoir to cars. Air pollution maps reveal a dramatic change.
Air pollution fell substantially as the city restricted car traffic and made way for parks and bike lanes.
www.washingtonpost.com
August 30, 2025 at 9:15 PM
Reposted by Johannes Weiss
Need a fast key/value datastore? The portfolio of Swift packages for building high-performance internet-scale services grew further this week with the preview of Valkey support: valkey.io/blog/valkey-...
Valkey · Introducing valkey-swift, the Swift client for Valkey
The new Swift client for Valkey is now in preview. Learn about its features and how it brings the performance of Valkey to the Swift language.
valkey.io
August 5, 2025 at 10:27 PM
Reposted by Johannes Weiss
Very excited to see the first cut of github.com/valkey-io/va..., which supports really lovely structured concurrency integration for accessing the client, pipelining commands, mixing that with transactions, and more! #swiftlang #valkey
GitHub - valkey-io/valkey-swift: Valkey client written in Swift
Valkey client written in Swift. Contribute to valkey-io/valkey-swift development by creating an account on GitHub.
github.com
August 4, 2025 at 8:56 PM
Reposted by Johannes Weiss
3 ways I used LLMs to actually learn Swift - A thread🧵

Who isn’t using AI to learn these days?
But it’s not just about shortcuts—it’s about learning smarter.
Here’s how I used LLMs as a beginner 👇
August 4, 2025 at 6:24 PM
@steipete.me Just checked out steipete.me/posts/2025/v... : Excellent product, thanks for sharing this (and the other) articles!!

Really happy you gave Hummingbird a try. Quick Q though: You write Xcode was difficult leading to giving up on Swift. Why not vanilla SwiftPM over Xcode&xcodebuild?
VibeTunnel: Turn Any Browser into Your Mac's Terminal | Peter Steinberger
We built a browser-based terminal controller in one day using Claude Code, named pipes, and Xterm.js. No SSH needed, just open your browser and start typing. Check and command your agents on the go!
steipete.me
August 3, 2025 at 12:50 PM