Developed targeted test coverage for the CalamityCall repository, focusing on the ReactionsModel and UserModel to enhance backend reliability. Leveraging Python and unit testing frameworks, the work introduced automated tests that validated CRUD operations and edge cases for both models, including scenarios with invalid inputs. By employing mocking techniques, the tests ensured that both standard and exceptional behaviors were thoroughly exercised, directly reducing the risk of regressions. All changes were committed with traceability in mind, supporting safer and more confident releases. This effort improved the overall test quality, contributing to more robust deployments and streamlined backend development practices for the project.