> ## Content Index > Fetch the complete content index at: https://commonmain.dev/llms.txt > Use this file to discover other available public pages before exploring further. # Kotlin Multiplatform Newsletter #23 - URL: https://commonmain.dev/kotlin-multiplatform-newsletter-23/ - Published: 2026-06-23T13:00:20.000Z - Updated: 2026-06-23T13:00:23.000Z - Author: Bogdan Codes - Tags: Issues We celebrate Kotlin’s 15th anniversary with free Hyperskill courses, dive into handling multiple inheritance using Class Delegation, and expose the silent "division-by-zero" trap in Kotlin Multiplatform. We also cover wiring up FCM Push Notifications in Compose (and the undocumented step that breaks iOS), handling precise decimal arithmetic for money in `commonMain`, building native macOS screen savers, and fresh UI libraries like Composables UI and Kore. Plus, an open Senior Engineering Manager role at Quo. ### **The Log** The only Kotlin Multiplatform and Compose Multiplatform news you actually need to know. [Kotlin is turning 15 – and now is a great time to take your Kotlin skills further](https://hyperskill.org/categories/37?ref=commonmain.dev) Celebrate Kotlin’s 15th anniversary this summer. Join Hyperskill now and get free access to our Kotlin courses — from language fundamentals to advanced development topics — through the end of summer. Available for new users only. ### Expect Actual Technical deep dives, or solving the "how-the-hell-do-I-test-this" problems. affiliate link — supports the newsletter at no extra cost to you ****Stop treating Kotlin like a black box! 🧠** To build truly performant multiplatform apps, writing code that just "works" isn't enough. We need to understand what the compiler is actually doing under the hood. That’s why I highly recommend [****Practical Kotlin Deep Dive**](https://skydoves.gumroad.com/l/kotlin-deep-dive?a=705284499&ref=commonmain.dev) by skydoves. This isn't a basic syntax guide, it breaks down Kotlin internals, bytecode, and coroutines. It’s been a total game-changer for me when writing and optimizing shared code. If you want to level up your Kotlin and KMP skills to a senior standard, you need this on your desk. [Get the Book ](https://skydoves.gumroad.com/l/kotlin-deep-dive?a=705284499&ref=commonmain.dev) [Multiple Inheritance in Kotlin. Class Delegation Closes the Gap](https://itnext.io/multiple-inheritance-in-kotlin-class-delegation-closes-the-gap-0928991eadb3?ref=commonmain.dev) Kotlin, like Java, gives you exactly one parent class. Most of the time that’s fine. Occasionally it isn’t, and you end up staring at two base classes that need the same behavior but already extend two different things. [The Kotlin Multiplatform division-by-zero trap](https://github.com/kotools/types/discussions/996?ref=commonmain.dev) If you write Kotlin Multiplatform code that involves integer division, you may have already hit this: the exact same expression behaves completely differently depending on which platform compiles it. [Push Notifications in Compose Multiplatform: The Setup Guide I Wish I Had (Including the Mistake That Cost Me 3 Days)](https://medium.com/@sijanneupane/push-notifications-in-compose-multiplatform-the-setup-guide-i-wish-i-had-including-the-mistake-dfc3b980ec03?ref=commonmain.dev) This article is the setup guide I wish someone had handed me before I started: how to wire up Firebase Cloud Messaging (FCM) in a Kotlin Multiplatform / Compose Multiplatform project, for both Android and iOS, and — more importantly — the one step that has nothing to do with your code and will silently break iOS if you skip it. [Floating point can’t hold a cent. BigDecimal can, until commonMain.](https://proandroiddev.com/floating-point-cant-hold-a-cent-bigdecimal-can-until-commonmain-0ba3d6c49115?ref=commonmain.dev) TL;DR — There are three ways to store money. Two of them bite back, and Kotlin Multiplatform takes the favorite one off the table. ### LazyColumn Compose Multiplatform tips, tricks, and code snippets. [Building a 3D Game in React Native + Kotlin Multiplatform](https://medium.com/@gabor.berenyi.california/building-a-3d-game-in-react-native-kotlin-multiplatform-526b3c2ddb6a?ref=commonmain.dev) Recently I built a 3D chess game in Compose Multiplatform: shared Kotlin logic, a 3D board behind a small renderer interface, and four native rendering backends for Android, web, iOS, and desktop. Today I rebuilt the same game on React Native to see what changes and what stays. [Building a macOS screen saver in Kotlin](https://zsmb.co/building-a-macos-screen-saver-in-kotlin/?ref=commonmain.dev) This article documents how I created my own custom screen saver for macOS, built almost entirely in Kotlin, using the powers of Kotlin Multiplatform to target macOS. [Introducing Composables UI](https://composables.com/blog/introducing-composables-ui?ref=commonmain.dev) After 2 years of iterations on Compose Unstyled, a brand new Compose library is born: Composables UI. [Kore](https://kore-3j8.pages.dev/?ref=commonmain.dev#home) Kore is a Compose Multiplatform design foundation that provides beautifully pre-styled components to help you build scalable and consistent design systems. ### The Dependency Graph Curated libraries, tools and plugins that won't break your Gradle build. - [**Deci**](https://github.com/Kimplify/Deci?ref=commonmain.dev) Deci is a Kotlin Multiplatform library for high-precision decimal arithmetic. Built for money, taxes, invoicing, and any workload where `Float`/`Double `cannot be trusted. - [**kVinInfo**](https://github.com/kabirnayeem99/kVinInfo?ref=commonmain.dev) A pure Kotlin Multiplatform library for VIN (Vehicle Identification Number) decoding, validation, and NHTSA API integration. - [**Vibrance**](https://github.com/romainguy/vibrance?ref=commonmain.dev) Natural color mixing for Kotlin and Compose Multiplatform. - [**Warden Supreme**](https://github.com/a-sit-plus/warden-supreme?ref=commonmain.dev) Warden Supreme is the evolution of the battle-tested WARDEN server-side key and app attestation library, augmented by Signum's *Supreme* KMP crypto provider for a consistent UX across Android and iOS. - [**Kamera**](https://github.com/Kashif-E/Kamera?ref=commonmain.dev) A modern camera library for Compose Multiplatform supporting Android, iOS, and Desktop with a unified API. - [**Sharingan**](https://github.com/mibrahimdev/Sharingan?ref=commonmain.dev) Live HTTP · MQTT · Bluetooth logging for Kotlin Multiplatform — iOS & Android, one API ### Careers Kotlin Multiplatform job postings and opportunities. affiliate link — supports the newsletter at no extra cost to you ****hackajob** • **Meet Archer, your AI job matching agent** 5x more interviews. Zero guesswork. Archer works 24/7 to match you with roles that fit your stack and seniority. You review the matches, not the job boards. [Create your free profile ](https://hackajob.com/talent/invite?referral%5Fid=ce111234ec9b294c075f&ref=commonmain.dev) [Senior Engineering Manager, Foundations](https://jobs.gem.com/quo/am9icG9zdDrSIwOjTXKoT63nWHbum6ME?ref=commonmain.dev) at [Quo](https://www.quo.com/?ref=commonmain.dev) **Remote - United States & Canada* We're looking for a Senior Engineering Manager to lead our Foundations team, the group that builds and scales the technical and organizational infrastructure the rest of Quo's engineering org is built on. Foundations is a uniquely cross-disciplinary team of mobile, web, and backend engineers responsible for the core systems everything else depends on: our GraphQL platform, client data sync, mobile frameworks (Kotlin Multiplatform), CI and testing platforms, and the core architecture of our client systems. --- #### 🚀 Get Featured! Got something interesting to share with the Kotlin Multiplatform community? [Submit your link](https://commonmain.dev/submit-your-link/) for a chance to get featured in the next issue of **commonMain.dev**. #### 🤝 Support the Build **commonMain.dev** is made possible by our partners. If you have a tool or service that helps KMP developers ship to production faster, we’d love to help you reach our community. [Collaborate with us](https://commonmain.dev/sponsor/). #### ✍ Code Review This newsletter is curated and written by a real human being. I’m always looking for ways to optimize the build. Was there something you liked or disliked in particular? Or did you find a bug in this issue? Simply **reply to this email** \- I read every comment from the community and take your feedback into account for the next release. Until next time, **Stay platform-independent!** Bogdan • Founder of commonMain.dev ![](https://storage.ghost.io/c/57/59/57597180-415a-44ab-aa77-38b4467c31d5/content/images/2026/06/kodee-mail-v1-upscaled-2-1-1.png) ## Sign up for commonMain.dev Every Tuesday, the few KMP links actually worth your time. Hand-picked, no AI filler. Join free Email sent! Check your inbox to complete your signup. Free forever · One email every Tuesday · No spam, unsubscribe anytime. Hand-picked by a senior engineer (8+ yrs) · Read by KMP engineers & tech leads.