Opt-in for experimental Kotlin API's in gradle files

In an Android module
In a Kotlin module
In all Kotlin modules

In an Android module

plugins {
    id "com.android.library"
    id "kotlin-android"
}

android {
    defaultConfig {
        kotlinOptions {
            freeCompilerArgs += [
                "-opt-in=kotlin.time.ExperimentalTime",
                "-opt-in=kotlinx.coroutines.ExperimentalCoroutinesApi"
            ]
        }
    }
}

In a Kotlin module

plugins {
    id "org.jetbrains.kotlin.jvm"
}

compileKotlin {
    kotlinOptions {
        freeCompilerArgs += [
            "-opt-in=kotlin.time.ExperimentalTime",
            "-opt-in=kotlinx.coroutines.ExperimentalCoroutinesApi"
        ]
    }
}

In all Kotlin modules

Add the following snippet to the root gradle.build file:

allprojects {
    tasks.withType(org.jetbrains.kotlin.gradle.tasks.KotlinCompile).configureEach {
        kotlinOptions {
            jvmTarget = "1.8"
            freeCompilerArgs += [
                "-opt-in=kotlin.time.ExperimentalTime",
                "-opt-in=kotlinx.coroutines.ExperimentalCoroutinesApi",
            ]
        }
    }
}