diff --git a/server/build.gradle b/server/build.gradle
index c19e171c90f96..d3c7d4089125c 100644
--- a/server/build.gradle
+++ b/server/build.gradle
@@ -414,6 +414,7 @@ tasks.register("japicmp", me.champeau.gradle.japicmp.JapicmpTask) {
     onlyModified = true
     failOnModification = true
     ignoreMissingClasses = true
+    failOnSourceIncompatibility = true
     annotationIncludes = ['@org.opensearch.common.annotation.PublicApi', '@org.opensearch.common.annotation.DeprecatedApi']
     annotationExcludes = ['@org.opensearch.common.annotation.InternalApi']
     txtOutputFile = layout.buildDirectory.file("reports/java-compatibility/report.txt")