Worked on the opsmill/infrahub repository to enhance backend reliability and developer experience by addressing a critical GraphQL validation issue. Focused on Python-based backend development, the work involved fixing a bug where negative offset and limit values were not properly validated in GraphQL queries. The solution introduced upfront validation logic, improved error messaging, and refactored the resolver to extract a dedicated validation function. Comprehensive test updates ensured robust coverage and reduced the risk of regressions. These changes stabilized user-facing results, improved error handling for invalid requests, and increased deployment confidence, demonstrating a methodical approach to backend quality and testing practices.