KotlinNative Demo

This repository is a Kotlin/Native demo. It compiles Kotlin/Native code into Android native shared libraries (.so) and Apple frameworks that are consumed by app modules.

What This Demo Shows

• Kotlin/Native shared library builds for Android ABIs.
• Packaging the native libraries into the Android app.
• Building and linking iOS framework artifacts from ui and shared.
• Building macOS arm64 Kotlin/Native binaries.
• A simple Compose UI that calls into native code.

Project Structure

• shared/: Kotlin Multiplatform logic module (network/JNI/native core).
• ui/: Shared Compose UI module with MVI state management.
• android/: Android app module that packages and loads the native libraries.
• iosApp/: iOS app module (SwiftUI + XcodeGen) that links the ui framework built by iosApp/scripts/prepare_kotlin_frameworks.sh.

How It Works (High Level)

• The shared module builds Kotlin/Native shared libraries for Android targets.
• The ui module hosts shared Compose UI and receives loaders from app layer.
• The android module copies those .so outputs into jniLibs.
• The Android app invokes native functions exposed by libshared.so.
• The iOS app links ui and shared frameworks under their build/xcode-frameworks outputs.
• The macOS target currently builds arm64 binaries only. A macOS app module is not included yet.

MVI Architecture Flow

flowchart TD
    AndroidApp[Android MainActivity] --> SharedApp[SharedApp]
    IOSApp[iOS SwiftUI ContentView] --> SharedUIBridge[SharedUIBridge]
    SharedUIBridge --> SharedApp

    SharedApp --> Store[SharedStore]
    Store --> State[SharedUiState]
    State --> Screen[SharedScreen]
    Screen --> Intent[SharedIntent]
    Intent --> Store

    Store --> Repository[SharedRepository]
    Repository --> Loader[SharedDataLoader]
    Loader --> NativeBridge[Shared / SharedBridge]
    NativeBridge --> SharedModule[shared module native networking]

    Repository --> Result[SharedLoadResult]
    Result --> Action[SharedAction]
    Action --> Reducer[SharedReducer]
    Reducer --> State

    Store --> Effect[SharedEffect]
    Effect --> SharedApp

Loading

Build

Android

./gradlew :android:assembleDebug
./gradlew :android:assembleRelease

Run the Android app from Android Studio by selecting the android run configuration, or install a built APK with:

adb install android/build/outputs/apk/debug/android-debug.apk

Windows

./gradlew :shared:runDebugExecutableMingwX64

iOS (with Xcode + XcodeGen)

cd iosApp
xcodegen
open iosApp.xcodeproj

Then run the iosApp scheme from Xcode. The pre-build script compiles the required ui framework and copies it into Xcode's framework search path.

macOS arm64 binaries

./gradlew \
  :shared:linkDebugSharedMacosArm64 \
  :shared:linkReleaseSharedMacosArm64 \
  :ui:linkDebugFrameworkMacosArm64 \
  :ui:linkReleaseFrameworkMacosArm64

Outputs:

• shared/build/bin/macosArm64/debugShared/libshared.dylib
• shared/build/bin/macosArm64/releaseShared/libshared.dylib
• ui/build/bin/macosArm64/debugFramework/ui.framework
• ui/build/bin/macosArm64/releaseFramework/ui.framework

There is currently no macOS app target to run directly. To run this on macOS, add an AppKit or SwiftUI macOS app and link ui.framework; the ui framework exports shared.

CI uses the same macOS arm64 Gradle tasks in .github/workflows/ci-mobile.yml.

Notes

• For native, TLS is not supported because this demo uses Ktor CIO. YouTrack: TLS sessions are not supported on Native platform

• This is a demo project intended for learning and experimentation.

Acknowledgements

• This README and parts of the setup were created with help from an AI assistant (OpenAI Codex).