Matt McKenna

24 Oct 2024

Made an #AndroidDev Starter Pack! Please let me know if I missed anyone so I can connect with them as well 😁 go.bsky.app/Etd57t6

I really liked this idea and wanted to join in on the fun and see how it felt as a library. Introducing Sea Glass for Compose. 🌊 SLKVinyl on Twitter suggested sea glass for Material Design 4. Inspiration: x.com/SLKVinyl/st...

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It’s easy to add the style with the seaGlass modifier. Also available as: • Components: SeaGlassButton, SeaGlassSurface • Styles: SeaGlassStyle, SeaGlassComponentStyle • Themes: SeaGlassTheme, SeaGlassMaterialTheme

Try it out and let me see what you make with it. Source and examples: github.com/mttmcknn/se...

Oh, it also supports Material You.

A little code behind the glass. You can give buttons and surfaces that frosted, softly tumbled look, with your own text and icons inside.

My favorite feature is the Tumble API. It adds a little wonkiness to the shapes, just for fun.

I've been working on an Android emulator plugin for Codex. Managing emulators with multiple agents was a mess, so I wanted each chat to have its own device that I could see and interact with directly. It's made it much easier to keep my agents and emulators organized.

It uses the new OpenAI MCP Extensions API to put the emulator right beside your chat. You can watch the agent work or take control, check Logcat, and send screenshots or recordings back to the chat.

github.comGitHub - mttmcknn/android-emulator-plugin: Run, control, and test Android emulators directly in Codex, with a live panel and a dedicated device for each chat.Run, control, and test Android emulators directly in Codex, with a live panel and a dedicated device for each chat. - mttmcknn/android-emulator-plugin

If you're using Codex for Android dev, give it a try and let me know how it works for you. github.com/mttmcknn/an...

Matt McKenna reposted

Bryan Cantrill

@bcantrill.bsky.social

13 Sept

The contagion of fear bcantrill.dtrace.org/2026/09/13/t...

bcantrill.dtrace.orgThe contagion of fear | The Observation Deck

9 Sept

Life’s been busy lately, and I finally found some time today to get caught up on dejavu! Dejavu turns Compose recomposition counts into test assertions, so you can catch regressions and protect the improvements you’ve already made. Here’s what’s new:

• Expanded test coverage: keyed SideEffect, changing remember keys, nested movable content, and newer Compose test APIs. • Platform fixes and validation: Android, JVM desktop, iOS, and Wasm!

github.comRelease DejaVu 0.5.0 — Compose 1.12 · mttmcknn/dejavuDejaVu 0.5.0 targets stable Compose 1.12 and adds regressions for its new runtime and testing behavior. Android Compose 1.11 remains supported, and DejaVu keeps its own version numbers. Compatibili...

9 Sept

Thanks to everyone who tried it, reported issues, contributed fixes, or shared! 💚 github.com/mttmcknn/de...

• Dejavu 0.4.0: support for Compose Multiplatform 1.11. • Dejavu 0.5.0: support for Compose Multiplatform 1.12, while retaining Android Compose 1.11 compatibility.

3 Aug

After 4.5 rewarding years at Square, my time there came to an unexpected end. It’s a transition that feels all too familiar right now, but it cleared the path for an amazing new opportunity. I'm excited to start my next chapter at Ramp!

Matt McKenna reposted

Sebastian Sellmair

@sellmair.dev

17 July

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!

Matt McKenna reposted

@tunji.dev

9 July

Experimenting with something new in the latest Heron release. Heron now let's you download a local inference model to translate text and it works completely offline on your device. Nothing gets sent to any server.

github.comGitHub - himattm/dejavu: A lightweight framework for tracking and asserting against Jetpack Compose recompositions.A lightweight framework for tracking and asserting against Jetpack Compose recompositions. - himattm/dejavu

3 July

Finally working on cleaning up PRs for dejavu, including working on Compose 1.11 support. github.com/himattm/dejavu

central.sonatype.orgMaven Central Publishing Limits

3 July

Side note: Jules gets very annoying very fast by reporting duplicate PRs all the time...

Matt McKenna reposted

Zac Sweers

@zacsweers.dev

16 June

Super sympathetic to Sonatype's situation, hosting isn't free. But announcing this with paltry limits and no public pricing options (a sales contact ain't it) is bad for everyone and going to be a major disruption to the JVM and Kotlin ecosystems. central.sonatype.org/publish/mave...

Matt McKenna reposted

Bridget Phillips

@jingibus.bsky.social

3 June

Maybe the most harmful thing about LLMs for a learning community is that you won't learn about anything unrelated to what you asked for.

Matt McKenna reposted

Cassidy

@cassidoo.co

27 May

look how they massacred my boy

Matt McKenna reposted

Mark Murphy

@commonsware.com

26 May

Hi! I shipped jetc.dev Newsletter Issue #315! Google I|O 2026! Compose Multiplatform 1.11.0! Android is Compose-first! And... an LLM-powered layout?!? jetc.dev/issues/315 #JetpackCompose #AndroidDev

Matt McKenna reposted

Chris Banes

@chrisbanes.me

26 May

Hunting down Jetpack Compose recomposition issues manually is a huge time sink I’ve spent the past few weeks using @mmckenna.me’s Dejavu to simplify this: - Write Dejavu tests to establish a baseline - Tell the agent to hunt for issues and A/B fixes - Profit

Matt McKenna reposted

Márton Braun

@zsmb.co

26 May

If you somehow missed the KotlinConf keynote last week, here are the top 10 KMP announcements with links to learn more about each 🧵👇

Matt McKenna reposted

Saket Narayan

@saket.me

24 May

Introducing Touch Robot, something that has materially changed how I write screenshot tests. We've been using it at Block for ~2 years to catch animation and gesture bugs that static screenshots miss. saket.me/touch-robot/

saket.meIntroducing Touch Robot, for writing interactive screenshot tests in Compose UIThe best parts of a UI are usually in motion. The bugs are too.

Matt McKenna reposted

Gergely Orosz

@gergely.pragmaticengineer.com

19 May

Situation 1: dev A thinks approach X is correct, dev B thinks Y is the right way. They argue and try to convince each other. Situation 2: dev A thinks approach X is correct, tells the LLM to implement it. There is SO MUCH learning in Situation 1, lost when using LLMs....

Matt McKenna reposted

Adam McNeilly

@adammc.bsky.social

17 May

Screaming into the void some thoughts on AI coding. androidessence.com/leave-me-beh...

androidessence.comLeave Me Behind | Android EssenceSimplified Android Development

github.comGitHub - yschimke/compose-ai-tools: Helping the Agents Compose the ThingsHelping the Agents Compose the Things. Contribute to yschimke/compose-ai-tools development by creating an account on GitHub.

3 May

Yes @schimke.ee !! Thank you for making this 💚 github.com/yschimke/com...

30 Apr

I built Dejavu because agents don't feel extra recompositions. They write Compose code that compiles and passes its tests while the UI quietly does ten times the work. Dejavu turns that hidden work into a failing test, giving the agent a count to optimize against.

Two lines in any Claude Code session: /plugin marketplace add himattm/dejavu /plugin install dejavu@dejavu

30 Apr

Dejavu is KMP, so the skills work across Android, JVM Desktop, iOS, and WasmJs. They cross-reference each other so the agent moves between them on its own. Try it on a composable that's been bugging you. Repo: github.com/himattm/dejavu Docs: dejavu.mmckenna.me

The standout is dejavu-perf-loop. You pick a composable, write a test asserting atMost=10, and run it. You read the failure, choose a cookbook fix, apply it, and rerun. Tighten the bound and keep going until the count matches the floor.

30 Apr

The floor isn't always zero. Some composables legitimately recompose N times when their inputs change, and that count is the right answer. The skill writes the assertion as exactly = N and locks it in. If the count already matches the floor, the cookbook step is skipped.

Today I shipped four skills, one for each part of the loop: • dejavu-onboarding: adds Dejavu to a project • dejavu-test-writer: authors recomposition tests • dejavu-error-triage: diagnoses failing assertions • dejavu-perf-loop: drives recompositions to their floor

Matt McKenna reposted

Chris Banes

@chrisbanes.me

chrisbanes.meHaze 2.0: A Pluggable Visual Effects EngineHaze 2.0-alpha01 turns blur into a pluggable effect, splitting it into a separate module and opening the door to custom visual effects built on top of a shared rendering infrastructure.

💠 Haze 2.0-alpha01 is out! This is a big release, splitting Haze up into layers, with the goal of enabling pluggable visual effects. Let me know what you think! chrisbanes.me/posts/haze-2...

Finally got around to bundling the skills I'm using every day into a repo and Claude Code marketplace so anyone can install them. I'm still rebuilding from what I was using daily at work, but we'll get there.

github.comGitHub - himattm/skills: My collection of Skills for AI agents.My collection of Skills for AI agents. Contribute to himattm/skills development by creating an account on GitHub.

Just a few commands and you're set. The marketplace manifest auto-refreshes at Claude Code startup so you'll get future skills and updates. I'd love to hear how it goes if you try it. github.com/himattm/skills

🎨 Color Snap 2026-04-28 #283D3B Pine 🟢🟢🟢 3/3

play.google.comColor Snap - Apps on Google PlayDaily color-matching challenge. Snap photos, build streaks, train your eye.

It's only day two and I've had so much fun finding thinks for this app so far. play.google.com/store/apps/...

mailchi.mpKotlin Weekly #508

27 Apr

Thank you for featuring Halogen!! 🥳

Kotlin Weekly@kotlinweekly.bsky.social

Kotlin Weekly #508 has just been published! - mailchi.mp/kotlinweekly...

Matt McKenna reposted

Adam McNeilly

@adammc.bsky.social

25 Apr

Wrote up something small about how I started using interface inheritance to handle inserting into multiple tables at a time in Room, when you have a common type used by multiple Daos and don't want to duplicate code. #AndroidDev androidessence.com/multi-table-...

androidessence.comManaging Multi Table Inserts With Room | Android EssenceSimplified Android Development

22 Apr

Hit Claude limits for the first time ever with Opus 4.7 It's somehow equivalent to my last 30 days of Opus 4.6 use. This makes the model not worth using imo.

androidweekly.netAndroid Weekly - Free weekly Android & Kotlin development newsletterAndroid Weekly is a free newsletter that helps you to stay cutting-edge with your Android Development.

20 Apr

Thank you for featuring Halogen! 🙌

Android Weekly@androidweekly.bsky.social

Latest Android Weekly Issue 723 is out! androidweekly.net/issues/issue... #AndroidDev #Kotlin

Matt McKenna reposted

Adam McNeilly

@adammc.bsky.social

15 Apr

Live now! Come hang out for some chill Wednesday night coding twitch.tv/adammc

twitch.tvTwitchTwitch is the world