diff --git a/libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/resources/testProject/hierarchical-mpp-multi-modules/mpp-additional/build.gradle b/libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/resources/testProject/hierarchical-mpp-multi-modules/mpp-additional/build.gradle
index 63063eb07cc..72dea38c702 100644
--- a/libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/resources/testProject/hierarchical-mpp-multi-modules/mpp-additional/build.gradle
+++ b/libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/resources/testProject/hierarchical-mpp-multi-modules/mpp-additional/build.gradle
@@ -5,6 +5,10 @@ apply plugin: 'kotlin-multiplatform'
 apply plugin: 'maven-publish'
 
 kotlin {
+    compilerOptions {
+        optIn.add("kotlinx.cinterop.ExperimentalForeignApi")
+    }
+
     js() {
         browser()
         nodejs()