diff --git a/build.gradle b/build.gradle
index fa73af6..7aef6d9 100644
--- a/build.gradle
+++ b/build.gradle
@@ -11,7 +11,7 @@
 
 java {
     toolchain {
-        languageVersion = JavaLanguageVersion.of(21)
+        languageVersion = JavaLanguageVersion.of(17)
     }
 }