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Hello, I'm looking for Nikolai Igotti please. I'm interested in integrating Kotlin Compose with the Vaadin framework, but unfortunately I lack knowledge on how the Kotlin Compose compiler plugin works and how it integrates with the concrete compose library implementation (such as compose-web). Anton Arhipov told me that Nikolai could offer me some docs/pointers/initial guidelines. Thank you :slightly_smiling_face:

&gt; Nikolai Igotti
You can contact me instead of Nikolay.

As far as I know Vaadin renders all components on server side. You want to wrap existing Vaadin components into @Composable functions?

Thank you for reaching out :slightly_smiling_face:

That is exactly correct. Vaadin components exist primarily on JVM; that's the environment where the `@Composable` functions will run and will create Vaadin classes, such as Button and Span. Perhaps the solution might be closer to Compose-Desktop because of targeting JVM?

I think I'm looking for a document which explains in detail how exactly Compose observes the changes done to the MutableState, and how can I plug in with my Vaadin-related functions :slightly_smiling_face:

&gt; Perhaps the solution might be closer to Compose-Desktop because of targeting JVM?
&gt; 
It is probably in between. You need a compose runtime library, which is built for JVM (desktop):
```import org.jetbrains.compose.compose

plugins {
    kotlin("jvm")
    id("org.jetbrains.compose")
}

repositories {
    mavenCentral()
    maven("<https://maven.pkg.jetbrains.space/public/p/compose/dev|https://maven.pkg.jetbrains.space/public/p/compose/dev>")
    google()
}

dependencies {
    implementation(compose.runtime)
}
```
and use an approach, which is used for Compose Web for DOM (“compose” dom elements into some existing DOM container)

You can look at <https://github.com/JetBrains/compose-jb/tree/composeExternalUI/templates/desktop-template|an example> how to integrate Compose with external UI framework.

Also you can look at <https://github.com/JakeWharton/mosaic|mosaic> - it uses Compose (another fork of it) to build a console application.

&gt; You can look at <https://github.com/JetBrains/compose-jb/tree/composeExternalUI/templates/desktop-template|an example>
Note that code can be not optimal there. Instead of `EmptyApplier`, you might want something like `Applier&lt;ExternalComponent&gt;`. But it is a good start.

Perfect, thank you, I'll study these resources :bow:

Couldn’t you just fork compose web and use your html classes (or kotlinx.html)?

<@U01JRLZH77T> that would make sense if I'd try to target client-side javascript. However, I'm trying to target server-side JVM Vaadin UI components.

Yeah, thats why replace js dom classes with kotlinx html (or your html lib). But the main implementation of compose dom runtime is the same.

I remember multiple cases of people implementing server-sided component with Compose. Here is an example <https://github.com/criske/compose-ssr>