diff --git a/schach/pom.xml b/schach/pom.xml
index 546c1ea..c7f3083 100644
--- a/schach/pom.xml
+++ b/schach/pom.xml
@@ -15,7 +15,7 @@
 
   <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-    <maven.compiler.release>21</maven.compiler.release>
+    <maven.compiler.release>17</maven.compiler.release>
   </properties>
 
   <repositories>
@@ -97,7 +97,7 @@
         <artifactId>maven-compiler-plugin</artifactId>
         <version>3.13.0</version>
         <configuration>
-          <release>21</release>
+          <release>17</release>
         </configuration>
       </plugin>