marcinmoskala.bsky.social @marcinmoskala.bsky.social · 25/09/2025With @preussler.berlin 👍 at #dcbln25 Thank you @droidcon.bsky.social for inviting me another time to this event! 051
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 18/09/2025To optimise, you must measure. To choose the right approach for performance measurement, you must answer the most important question: What do you want to measure? 100
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 25/08/2025Which one really scales better for high-concurrency workloads? 🤔 Are there reliable benchmarks comparing coroutine performance with Loom’s virtual threads? 100
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 25/08/2025Only 7 days left to buy Coroutines Mastery at a better price! 000
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 22/08/2025Boost your Kotlin performance with Project Loom's virtual threads! Say goodbye to `Dispatchers.IO` and run blocking code like it's non-blocking. Faster, simpler, smarter. ⚡ 🔗 Dive in now: kt.academy/article/disp... 100
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 22/08/2025Curious about Rich Errors in Kotlin? Here is the first KEEP document, explaining their motivation and implementation: github.com/Kotlin/KEEP/...github.comKEEP/proposals/KEEP-0441-rich-errors-motivation.md at main · Kotlin/KEEPKotlin Evolution and Enhancement Process. Contribute to Kotlin/KEEP development by creating an account on GitHub. 010
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 21/08/2025Updates to MutableStateFlow should be made using the update function; otherwise, conflicts might cause some updates to be lost. 120
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 15/08/2025I will be speaking at #JDDKrakow on October 21-22, 2025! Let's meet in Krakow, Poland - join the conference at: jdd.org.pl #JavaDevelopment #JavaConference #SoftwareEngineering #TechConference #Krakow 020
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 15/08/2025A lightweight wrappers over arrays, providing efficient collection processing functions, immutability, equality, and proper type hierarchy. Those are arrays done well, I love it! github.com/daniel-rusu/... #Kotlin #ImmutableCollections #FunctionalProgramming #SoftwareEngineering #DeveloperTips 120
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 14/08/2025Ready and excited for today's sessions! Can't wait to share this content with you all. See you all very soon! webinar.kt.academy/why-you-shou... #Kotlin #KotlinCoroutines #Concurrency #AsyncProgramming #DeveloperCommunity 010
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 13/08/2025Still debating whether you should introduce coroutines—or where to even begin? Skip the internal tug-of-war and bring your toughest questions to my live Q&A TOMORROW! I’ll be dedicating extra time to answer everything you throw. Last chance to sign up: webinar.kt.academy/why-you-shou... 000
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 12/08/2025Coroutines power-user? Grab my brand-new Flow Cheat-Sheet—operators, builders, the whole buffet. 👇 cheat-sheet.kt.academy/flowcheat-sheet.kt.academyFLOW IN KOTLIN COROUTINESNeed a no-fluff guide to Kotlin Flow? Sign up and grab the Flow in Kotlin Coroutines Cheat Sheet—a concise, high-impact PDF that turns complex async concepts into copy-paste-ready code examples. 100
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 11/08/2025Many ask me how to stay in touch with what's happening in Kotlin. My answer is simple: Kotlin Weekly! kotlinweekly.net 000
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 11/08/2025In 3 days, we go live! ⏳ Seats are filling up! 👉 webinar.kt.academy/why-you-shou... #KotlinCoroutines #StructuredConcurrency #ReactiveProgramming #SoftwareEngineering #KtAcademy 000
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 08/08/2025Most people do not even think about cancellation, but it is extremely important, and both Android and backend developers benefit from Kotlin Coroutines cancellation mechanisms. Let me give you some examples. 100
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 06/08/2025Coroutines are incredibly powerful, but their hidden complexities can trip up even experienced developers. While this topic is not new, my recent webinar on "Mistakes You Make Using Kotlin Coroutines" was packed — and for good reason! 120
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 05/08/2025Teaching Flow for years has taught me one thing: developers, including myself, love quick references. So here’s mine—totally free. Join the list, grab the PDF, and tell me what you think! 👉 cheat-sheet.kt.academy/flow 000
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 04/08/2025Who should join my free webinar, “Why You Should Use Kotlin Coroutines”? Anyone who wants to START USING COROUTINES CORRECTLY in real projects. 👨💻 Developers 🧑💼 Team Leads & Tech Managers 📊 Project Managers (with a technical background) Reserve your spot: webinar.kt.academy/why-you-shou... 000
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 01/08/2025What are the advantages of Kotlin over Java TODAY? Since Kotlin gained popularity, Java has started dynamically introducing features inspired by Kotlin. But what does Kotlin still have up its sleeve, and is it reachable for Java? Here is the list of the most important advantages: 100
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 31/07/2025Where should I keep me state in Compose? In component, view model, data layer or outside? This question can be reformulated as: How long do you want it to exist? 100
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 30/07/2025Kotlin Coroutines provide special support to interoperate with Java, Swift and JavaScript. Thanks to that, calling suspending functions is a breeze. 100
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 29/07/2025Many devs start using technology without understanding it first. That is fine, but some technologies give fake confidence, and devs misuse it without even realizing it. Let me use Kotlin Coroutines as a case study. Thread 👇🧵 120
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 28/07/2025Testability is one of the most important advantages of Kotlin Coroutines. It supports operating in virtual time, which lets us write precise, fast, and deterministic tests for cases that are hard to test with other libraries. You can easily check any scenario and assert how much time it would take. 100
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 25/07/2025Are you also annoyed by the fact that capitalize was deprecated and the replacement is crazy long? I am, but why did it actually happen? 100
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 24/07/2025VOTING 👇 What’s the #1 reason developers avoid or struggle with Kotlin Coroutines? 1️⃣ Seems too complex 2️⃣ Legacy code (RxJava) 3️⃣ Unclear best practices 4️⃣ Don’t know where to start Vote and share your experience in the comments, I’m really curious to hear your stories! 000
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 23/07/2025Dispatchers.Default and Dispatchers. IO share the same pool of threads, but each has its own independent limit. The pool is unlimited, and threads are created as needed. 100
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 22/07/2025Using apply to make SendGrid API usable 👍 100
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 21/07/2025Never make blocking operations on suspending functions without appropriate dispatcher! Most coroutines run on a small pool of threads (Main in Android, Default on backend), and blocking can easily cause thread starvation. The simplest way to fix that is using IO dispatcher, there are better options: 110
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 18/07/2025To turn a function into a flow that emits its result, you can just use flow builder with emit. Many projects define a function for that. You can also turn a lambda function using asFlow. 100
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 17/07/2025There is amazing interoperability between Kotlin Coroutines and RxJava/Reactor❗ 100
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 16/07/2025Have you known that in Android Studio you can preview animations, controlling their time or starting them in slow motion. 🐌 100
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 15/07/2025Kotlin allows turning nearly any function into a fluent single-expression style. Some love it, some hate it. Let's see how it works, discuss the pros and cons, and decide whether we should do it or not. 100
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 14/07/2025One of the most confusing comparison in Kotlin Coroutines is between CoroutineScope and coroutineScope. 110
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 11/07/2025In Kotlin we implement interface intersection types using interface delegation. This way we can simply aggregate functionalities of two interfaces into one class. This ScopedRise comes from Arrow library. 000
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 10/07/2025Say hello to Kotlin stdlib atomics! One of the most important tools for concurrent applications and libraries is now standarized, multiplatform and really efficient. 💪💪💪 100
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 09/07/2025A coroutine can only be cancelled when it gets suspended, so blocking or CPU-intensive operations often need a special attention to support cancellation. 110
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 08/07/2025Dispatchers. IO.limitedParallelism(n) creates a dispatcher that is limited to n threads. It has as little to do with Dispatchers. IO as it has with Dispatchers.Default. I think that is an unintuitive API, so some people prefer defining a top-level function. 010
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 07/07/2025I am always disappointed when I see that in Kotlin, but I see it surprisingly often. It makes no sense to make an async call and immediately await its completion. You should call await after the last async. 100
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 04/07/2025Have you ever wondered why toUpperCase and toLowerCase were deprecated in Kotlin? The original reason was the Turkish language. 100
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 04/07/2025Are your coroutines silently failing? Don’t worry I know a few tricks that can help you eaisily. We’ll cover: ✅ Sync vs async mistakes ✅ Dispatcher misuse ✅ Cancellation gotchas ✅ Structured concurrency traps 📅 July 10 — 2 time zones 👉 Sign up webinar.kt.academy/common-mista... 000
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 03/07/2025Exceptions should not be represented with object declarations❗ Even though they look like having no mutable state, they do - each exception contains stacktrace, so each exception must be unique. 010
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 02/07/2025People often misuse SupervisorJob, what leads to terrible mistakes❗ Let me explain how it should be used, and how it should be not. 110
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 01/07/2025A fake interface constructor returning a private class or object expression is a very common pattern in Kotlin team libraries. It allows us to expose only the interface, which is safe and offers maximum API flexibility. 120
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 30/06/2025Kotlin stdlib provides simple but very useful functions that can be called on any value, known as scope functions. Each has its purpose and use cases where it truly shines. Let's discuss let, also, takeIf, apply, with and run. 100
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 27/06/2025There is no other feature that shaped so strongly what Kotlin looks like today! Extension functions, one of the most beloved Kotlin features, turned out to be likely the most influential one. Let me explain briefly 👇🧵 110
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 26/06/2025Did you know that JetBrains is now in Poland, and recruiting like crazy?! 010
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 26/06/2025One important challenge in a bigger project is transforming nested objects. The default solution is using copy; the popular library that helps with that is Arrow Optics, but soon, we might also get a new feature to help us: copy var. 👇🧵 100
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 25/06/2025One common mistake is using UI thread for everything on an Android application. Let’s discuss how to property manage dispatchers on smaller and bigger Android applications. 👇🧵 100
marcinmoskala.bsky.social @marcinmoskala.bsky.social · 24/06/2025That game was hard to prepare, but I believe now you will have a lot of fun plying it :heart: I challenge you now! Test your coroutines understanding withi this new game! kt.academy/article/game... 000
