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kotlinlang

Hi! When using Kotlin with Gradle, should I define `java.toolchain` or `kotlin.toolchain` in my `build.gradle.kts` or both? What is the difference between the two?

I use the following in my Kotlin JVM project for the Kotlin source code:
```    kotlin {
        jvmToolchain(&lt;My Javaversion&gt;)
    }```
If the project also has Java code you can use a toolchain for that.
```java{
    toolchain {
       anguageVersion.set(JavaLanguageVersion.of(&lt;My Java version))
    }
}```
Have you checked the Gradle documentation regarding toolchain? <https://docs.gradle.org/current/userguide/toolchains.html>

<https://kotlinlang.org/docs/gradle-configure-project.html#gradle-java-toolchains-support|https://kotlinlang.org/docs/gradle-configure-project.html#gradle-java-toolchains-support>

only one of them. It is up to you what to use exactly

<@U58GRE73J> That was also my understanding. So in a pure Kotlin project, it doesn't actually matter?

yes, even in mixed Java/Kotlin it does not matter. DSL in Kotlin extension for now exists for convenience. In the future that may change for Kotlin-only projects.