Cheeky question. What does

<http://kotlinlang.org|kotlinlang.org>

use for frontend?

With compose-html, how do I observe scroll offset? (i'm accepting kobweb extensions as well 😀)

For some reason my wasm app started throwing

Module not found: Error: Can't resolve './skiko.mjs' in '/path/build/wasm/packages/project-name/kotlin'

but it worked fine a few days ago, any ideas what could be causing this? The only things that really come to mind are that I've added Coil3 and Skydoves ColorPicker

Is the file available for download anywhere perhaps?

Hello everyone I ran into a problem in my application - when the browser page is reloaded, the application is not rendered (an empty white page). In chrome inspector, you can see that the files index.html / app.the js and 2 .wasm files are loaded from the cache. What could be the reason for this behavior?

After switching from

CanvasBasedWindow

to

ComposeViewport

i found that after pressing Tab the canvas becomes focused and gains a distracting white outline (on chrome). Is there a way to apply CSS to the canvas? It's under shadow-root so normal stylesheets don't affect it.

hi there I am making a kotlin mobile app and I will have to let the users use it directly from a website how can I do that

Finally got the chance to report the font loading bug on web. Opened an issue at: https://youtrack.jetbrains.com/issue/CMP-9075/Square-placeholders-shown-before-loading-custom-fonts-on-Web

Now that Compose Web is in Beta, are there any plans to allow deleting characters while holding down the shift key? I think it would help it'd really help the user experience with any CMP Web app that involves typing. Another thing that's sorta on my wish list, is that native web apps allow you to start typing as soon as the tab is opened (such as any search engine or ai chatbot website). I haven't figured out a way to do this with CMP Web that doesn't involve getting the user to mouse click on the page first.

Hi, I found a bug in how multi-touch events are handled in compose-web. The issue was opened a few days ago: https://youtrack.jetbrains.com/issue/CMP-9030/wasm-canvas-incorrect-handling-of-multi-touch-input I have a fix for it as I identified the faulty part in the pointer event handling implementation specific to compose/web. What is the process for upstreaming such change ? In the Github contribution guide, it is explained that opening PRs on Github is not accepted for the compose/ui subproject. Thank you

do i remember wrong that there is a way to have wasm fallback to js? how is that done? can't find it in the docs

How do i change the distribution path of a wasm compose app? When i use the

distribution

block, the composeApp.js and many other files are not included in the output

wasmJs {
        browser {
            distribution {
                val rootDirPath = project.rootDir.path
                outputDirectory = File("$rootDirPath/dist/${project.name}") // <- 
            }
        }
        binaries.executable()
    }

I'm running

wasmJsBrowserDistribution

to package my compose web wasm app but the distribution contains 2 wasm files with weird names. is that normal? I expected to have just one .wasm file with the name is specify in the distribution block

~~Im facing this issue with embedding compose web inside of an iframe~~* even though i set the height of the iframe to be 400px, the contents of it end up being 404px and it causes the compose app to scroll. this is probably some styling issue, but i cant figure it out. any ideas? * Turns out this has nothing to do with the iframe. just running the app separately scrolls in place, even if the body is width + height 100%

Hi guys, As now we have

webMain

as web main source set. so i was trying to use the

WebElementView

composable there in webMain , but its not resolving(not found). Its available in jsMain and wasmJsMain only. Why its not available in webMain? most of the compose things which were available in wasmJs or js, should be available there in webMain, right? or am i missing something?

(Cross posting from #CDFP59223) Hi! I heard in a lightning talk from the Kotlin Conf 2025 that Compose Multiplatform on Web (with Wasm) is rendered on Canvas. How does that work? Are there any resources diving into rendering? I have a bunch of questions like • Does it write ui updates as bytes into a shared memory and the web browser reads from it as a stream and sends that to the canvas? • Does it calculate/render the compose tree and send that over the browser where it converts it as UI?

Hi team, When I upgraded to Compose Multiplatform

1.9.0

(from

1.8.2

), it seems that the testing has stopped working. Specifically, the

runComposeUiTest

calls are no longer running. Has anyone else encountered this issue?

What are the ways we can reduce caching of wasm binary? I have this challenge in that my client has to reload/refresh page to update the app. If they just reopen they still get the old app

I've been pulling in my composeApp as a module using the autogenerated "composeApp.mjs" so that I can grab it as a module and call kotlin from javascript. However that import intermittently fails (as in your compose wasm app does not start) with error like "can't find the function _malloc in compose and skiko." I think I've narrowed it down to my app (the internal compose parts) calling skiko before its really up. So I reworked the composeApp.mjs (with AI help) to wait for skiko to fully come up first:

import * as skiko from './skiko.mjs';
import * as joda from '@js-joda/core';
import { instantiate } from './composeApp.uninstantiated.mjs';

export async function initComposeApp()
{
    if (skiko.ready)
    {
        await skiko.ready;
    }
    else if (typeof skiko.instantiate === "function")
    {
        // fallback for older skiko
        await skiko.instantiate();
    }
    const { exports } = await instantiate({
        './skiko.mjs': skiko,
        '@js-joda/core': joda
    });
    return exports;
}

So far it appears to be working. I figured I'd post this here, because I think anyone else who is trying to use their composeApp as a module will hit the same problem.

Hi all! I am developing a multiplatform compose app that supports Google Oauth SSO for iOS, android, desktop, and wasmJs. For wasmJs, the new way of supporting Google Oauth is with GIS which requires you use a premade HTML element included in the library. As you can imagine, this is a problem since compose for wasmJs uses canvas, and there is no way to include HTML elements in canvas. The old way of doing it using GAPI would work since it can be done completely in JavaScript. But GAPI is deprecated and will be removed. How should this be done for Compose multiplatform for wasmJs?

Hello, I'm an Android developper with < 2 years of Compose experience (on Android) and ~15 years of Android Java / Kotlin. I'm familiar with "entry level ops" (I consider myself a "mobile ops", the Gradle and CI are my friends). I want to develop a small website for a group of friends where we can upload photos, add tags / metadata to them, and browse throught them. I'd like to code this in Compose obviously. My knowledge of JS / TS is around 1% and I'd like to keep it as low as possible to keep my sanity as high as possible. Does it look like a plan or am I greatly overestimating my skills? If you have any usefull ressources about hosting images I'll glady read them, there's thousands of solutions but I don't have the experience to know which one fits my needs.

Does Compose web have an exposed

ContextMenuArea

equivalent for a right click menu anchored to a specific component? That composable actually exists, but it's internal and only for text selection, unlike the desktop counterpart.

How can I use fonts available to the browser on Compose Web? I've tried the following and all of them render as roboto. I also tried preloading, but still the same result

listOf(
    "sans-serif",
    "sans",
    "roboto",
    "system",
    "Arial"
).forEach {
    val fontFamily = FontFamily(SystemFont(it))
    Text("The quick brown fox 🦊😍🤔 ${it}", fontFamily = fontFamily, fontSize = 32.sp)
}

Hello, are there plans of development of WASM/Browser + Ktor packages for SEO in short term? I am new to this SEO topic and have written a complete e-commerce in Kotlin/WASM with Compose multiplatform, but I could not find the complete way achieve a good work here. My little understand of the task tells me I should send an initial HTML for crawlers from Ktor. and displays it until the WASM finishes loading, This transition is the major problem: We have no way to use this initial html for a smooth transition to WASM, therefore making the Kotlin/WASM Compose less competitive than other technologies in terms of SEO. Am I wrong or missing something here?

Hi i would like to know if its possible to integrate compose web with adsense web ads, can use js/html elements like we can do for ios?

Calling all Compose Multiplatform for Web devs! 🌐 We’re gathering real stories from developers building with Compose Multiplatform for Web. 🗣️ Tell us about your experience – which use case fits your project best? ⚡ Instant web trials 🛠️ Internal applications, such as dashboards and admin panels 🤝 Sharing design system components with colleagues 💡 Or something else? ⚙️ What worked well — and what could be better? 🔗 Share a short note about what you’re building and add a project link if you’d like! The best quotes will be featured on our new Compose Multiplatform for Web landing page to highlight real developer experiences. Drop your thoughts in the thread and help inspire others to try Compose Multiplatform for Web! 💬 Slack Conversation

My app locks up while i am preloading emojis on the web. This results in a 2 second freeze (nothing is interactive and the app is unresponsive). The font is Noto Colored Emoji and it's 25mb. is this expected or a bug? Am i missing some option to load this async?

I want to load monochrome font emojis and at a later stage load colored ones Right now if i try to load the monochrome ones and at a later stage load the colored ones, nothing happens. I think it's because it's the exact same 'glyphs' in both. Is it possible to update the font somehow? maybe wipe the font cache? I can't find something related

Hello, any opinion about creating some kind of Netflix app in compose multiplatform web? (I say Netflix just an example, because everyone knows it). Any recommendation about which would be the right choice between wasm or compose html frameworks like kobweb? My concerns about this: • Potential performance issues when rendering nested lists • Potential issues with missing features in the player or drm content, or streaming performance Any hint? Maybe is too early to try this on a enterprise project? Thanks!

👋 Trying to capture keyboard events using

Modifier.onKeyEvent

, this seems to work only after the Compose canvas is focused. So I either need to first click on it, or add a bit of JS that finds the canvas and call

focus()

on it... Is this a known issue and/or is there a trick?