Emmanuel Valentin focused on backend reliability for the apache/gravitino repository, addressing a catalog update error reporting issue that previously misrepresented enable and disable operations. He enhanced the error handler in Java to preserve the original operation type from incoming requests, ensuring that user-facing messages accurately reflected the actual operation performed. To validate these improvements, Emmanuel expanded unit testing in TestCatalogOperations.java, covering both enable and disable scenarios. His work improved observability and reduced debugging time without introducing user-facing disruptions. By concentrating on precise error handling and robust test coverage, Emmanuel demonstrated depth in Java backend development and test-driven engineering practices.