diff --git a/userspace/engine/rule_loader.h b/userspace/engine/rule_loader.h
index fe358f5a..4a270e49 100644
--- a/userspace/engine/rule_loader.h
+++ b/userspace/engine/rule_loader.h
@@ -250,7 +250,7 @@ public:
 	                 const context& ctx);
 
 	void set_schema_validation_status(const std::vector<std::string>& status);
-	std::string schema_validation();
+	std::string schema_validation() override;
 
 protected:
 	const std::string& as_summary_string();