diff --git a/Kotlin/build.gradle.kts b/Kotlin/build.gradle.kts
index 8cac6e52..f1d49699 100644
--- a/Kotlin/build.gradle.kts
+++ b/Kotlin/build.gradle.kts
@@ -12,7 +12,7 @@ repositories {
 
 java {
 	toolchain {
-		languageVersion = JavaLanguageVersion.of(8)
+		languageVersion = JavaLanguageVersion.of(21)
 	}
 }