diff --git a/build.gradle.kts b/build.gradle.kts
index 831d22a..e7a33e3 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -22,7 +22,7 @@ version = "0.0.1-SNAPSHOT"
 
 java {
     toolchain {
-        languageVersion = JavaLanguageVersion.of(22)
+        languageVersion = JavaLanguageVersion.of(21)
     }
 }