Guess what, my new health insurance app, not every Spanish resident has two last names! And yeah, read this: www.kalzumeus.com/2010/06/17/f...

Women belong in tech

Something big might happen to the Kotlin Multiplatform Ecosystem 👀 We were never too happy about how Kotlin publishes and resolves KMP libraries. It takes up significantly more space than it has to, produces a ton of artifacts and Maven modules, and is just... complex!

Something that I really enjoy about working at JetBrains is dogfooding everything all the time: IDEA, its plugins, the Kotlin Gradle Plugin, Kotlin itself. So cool to file bugs and see them picked up, triaged and fixed!

Metro 1.3.0 has rich diagnostics and experimental runtime tracing! github.com/ZacSweers/metro/re...

Metro 1.2.0 has Hilt interop, provider inlining, improved compiler performance, and leaner runtime primitives! github.com/ZacSweers/metro/re...

Okhttp 5.4 interceptors can do more. 🎸 square.github.io/okhttp/chang...

Here are the slides: speakerdeck.com/zacsweers/me...

KotlinConf'26 started today in Munich, and there’s a lot to announce. Kotlin is easier than ever to get started with, and it now powers some of the most-used apps in the world – both on the backend and mobile. 🧵 Here are the highlights from the opening keynote.

I'll be giving a talk about Metro's internals tomorrow at @kotlinconf.com! This'll be an advanced talk that assumes familiarity with Metro, and is a sort of part 2 of my "Navigating Dependency Injection with Metro" talk last year. You can find it here: www.youtube.com/watch?v=jVfm...

Metro 1.1.0 and 1.0.1 are out now! This is largely a performance release. They are identical except 1.1.0 drops Kotlin 2.2.0 - Improved compiler performance - Lots of tracing improvements - SwitchingProvider now generates tableswitch bytecode - Kotlin 2.4.20 support github.com/ZacSweers/metro/re..

Prime Minister Pedro Sánchez and I are deepening our cooperation in energy, AI, and digital sovereignty — and we have a goal to double two-way trade between Canada and Spain. Thank you for the jersey, and see you at the World Cup! 🇨🇦 🇪🇸

Metro reaches 1.0! It's the proudest work of my career and I strongly feel this is how dependency injection in Kotlin should be. Thank you to everyone that's contributed and helped this project get to where it's at. Metro wouldn't be where it is without you. www.zacsweers.dev/metro-is-sta...

Metro 1.0.0-RC3 is out now and promotes function providers to the default! github.com/ZacSweers/metro/re...

A couple of months ago I was laid off by Block. I’ve mostly been doing dad stuff since then but I’m very gently looking to start having conversations and figure out what’s next for me. I’d love to chat with anyone that thinks I might be a good fit! gordonfontenot.com/hire-me

Barcelona is gorgeous this time of the year.

I know there's a lot of people that worked on this behind the scenes but on top of Ralf and Tom, I also wanna give a huge shout out to Joel Wilcox and Jacob Applin for a ton of contributions, pairing sessions over tuple, and starting work with me on Metro as far back as January 2025. Hire them!

We're wrapping up our migration to Metro internally for Square Android. I summarized some of our challenges and steps we took in a blog post. If you use Dagger 2 for a Kotlin project, then you should migrate to Metro sooner rather than later. engineering.block.xyz/blog/metro-m...

Metro 1.0.0-RC1 is out now! Last call for feedback on the public, non-experimental runtime/metrox/gradle APIs! github.com/ZacSweers/metro/re...

Metro 0.13.0 adds top-level contribution providers, Circuit code gen, and a new @DefaultBinding annotation. This also removes most deprecated APIs as Metro prepares to go stable (!!). If you have runtime API feedback, now is the time! github.com/ZacSweers/me...

Timmy's at the train station in Alicante, Spain

I built a tiny IntelliJ IDEA plugin for something that had been bothering me for years github.com/saket/intell...

KotlinPoet 2.3.0 supports typealias declarations inside types, has new convenience API for adding annotations and ships with a healthy dose of bug fixes. Time for a version bump! 🤜🤛 github.com/square/kotli...

Metro 0.12.0 introduces implicit class keys, raises some min JVM/Gradle versions, drops some deprecated targets, and the usual host of other improvements and bug fixes! github.com/ZacSweers/metro/re...

✊🏻

What happens to Square / Block Android OSS projects post layoffs? Let's start with some context OSS at Square is mostly a happy accident. Jack hired Bob, who's job was attracking world class engineers, and he did that through talks & OSS.

Metro 0.11.0 is out now, along with a new proposal system called MEEPs! www.zacsweers.dev/metro-0-11-0... Release: github.com/ZacSweers/me...

v1.117 is live! We rolled out support for Bandcamp embeds. Now you can play songs right inside posts! We're big fans of Bandcamp and everything they do to support artists. Upgrade to the newest app version and give it a try 👇 caribouband.bandcamp.com/album/butter...

Dear Competition Bureau Canada...

Re: Dependency Injection vs. Service Locators www.zacsweers.dev/re-dependen...

It is the year 2026, people are still confused about compileSdk and targetSdk. (e.g. you can have targetSdk that is higher than compileSdk) www.liutikas.net/2026/02/13/R... Maybe this will explain it a bit more. #android

Just published "Where are all the staff+ Android product engineers?" www.zacsweers.dev/where-are-th...

Today is Bandcamp Friday - Bandcamp is waiving their fees and passing the funds directly to the artists - so I went shopping. Got the entire Spiritbox discography and a few As I Lay Dying and Parkway Drive albums. One step closer to cancelling my Spotify subscription!

written ’cause we don't all get this right

🚨 NEW EPISODE 🚨 Everyone’s watching Davos - so we’re talking about some of the other European news. This week: potatoes in Berlin 🥔, a leaked “Made in Europe” proposal, and an interview with a sitting UK cabinet minister on the UK’s “reset” with the EU. www.europeanspodcast.com/all-episodes...

As great powers abandon rules and values for their own interests, middle powers like Canada have a choice: compete with each other for favour or act together with impact.

Giving it a shot

If your engineering team is 'senior-only' + AI-assisted… where do tomorrow's seniors come from? New blog post on the 'disappearing middle': chrisbanes.me/posts/disapp...

Sharing the Resonant Computing Manifesto I just signed: resonantcomputing.org, I agree with the vision it outlines. Check it out, and if it resonates with you - join me in signing it.

Canada stands with Ukraine. Our new loan guarantees and financing will support a just and lasting peace — and help the Ukrainian people rebuild and recover.

It makes no sense to me that the shutdown button for an iPhone is located under General Settings.

Jesse and Jake were my CN Tower. I only worked with them occasionally, but I always felt reassured just knowing they were around if I needed help. I'm mad our company lost both of them in the same week, and I'm afraid the entire Android OSS community will feel the ripple effect in the days to come.

Cash Android has recently switched to Metro, a new, fast dependency injection framework built for K2. That was a fun project and we're really happy with the results! Sharing details on how we approached the migration to help teams adopt Metro: code.cash.app/cash-android...

I'm surprised how bad Gboard's predictions still are in 2025, especially in languages that are not English. This feels like an area where LLMs surely would shine, but apparently not? Or Google just doesn't care enough about Gboard?

In a highly modularized codebase, typing full Gradle task names can be tedious. Gradle supports task name abbreviation: just type the shortest unique prefix. If ambiguous, Gradle suggests candidates. ⚠️ Use locally for speed, but keep codebase references explicit for readability!

🚇 New episode coming in hot! We’re talking Metro, Zac Sweers’ new Kotlin Multiplatform-first DI library. Fast, focused, multiplatform magic. 📅 Oct 8 on Twitch

Things that make me grumpy: - Friends who send five one-word messages vs one five-word message. - Mobile operating systems that don't batch notifications and have no problem buzzing me five times within five seconds.

📣 The KotlinConf'26 Call for Speakers is OPEN! Share your Kotlin expertise with the world – server-side, web, desktop, mobile, AI/ML, and more! Submit your proposal and get a chance to speak at the year's biggest Kotlin event! 👉 https://kotl.in/conf26-submittalk 👈