Build Pipeline

When JNI is enabled, Kreate wires a fully automated native build pipeline into your Gradle build. This page describes the individual tasks, their execution order, and how the compiled library is made available at runtime.

Task Graph

compileKotlin
    └── kreate-jni-build
            └── kreate-jni-initialize

kreate-jni-build is hooked into the Kotlin compile pipeline via executeTaskBeforeCompile, ensuring the shared library is always rebuilt before Kotlin compilation begins.

`kreate-jni-initialize`

Scaffolds the native C++ project if it does not exist. See Project Scaffolding for the full details on what is generated.

Property	Value
Task type	`InitializeCppProject`
Input	`projectDirectory` (root JNI dir), `projectName`
Output	`<projectDirectory>/<projectName>/`
Runs	Before `kreate-jni-build`

`kreate-jni-build`

Invokes CMake in two steps to configure and build the shared library.

Step 1 — Configure:

cmake -S . -B <projectDir>/build -DCMAKE_BUILD_TYPE=Release

Step 2 — Build:

cmake --build <projectDir>/build --config Release

The build type defaults to Release. The compiled shared library (.so/.dylib/.dll) is placed in <projectDirectory>/<projectName>/build/.

Property	Value
Task type	`BuildNative`
Input	`workDir` (native project dir), `buildType`
Output	`<workDir>/build/`
Default build type	`Release`
Runs	Before every `compileKotlin` task

Runtime Library Path

After the native build, Kreate automatically configures all Test and JavaExec tasks with the correct java.library.path so that System.loadLibrary() resolves the shared library without any manual setup.

The following JVM argument is injected:

-Djava.library.path=<projectDirectory>/<projectName>/build

Both task types also gain an explicit dependsOn("kreate-jni-build") dependency, ensuring the library is compiled before any test or run task executes.

Loading the Library in Kotlin

object NativeLib {
    init {
        System.loadLibrary("example") // matches CMake target name
    }

    external fun hello(): String
}

05 May 2026