Developed a comprehensive test suite for the necysc_app core models within the fullstackatbrown/project-necysc repository, focusing on backend reliability and data integrity. Leveraging Django and Python, the work validated Applicant model defaults, data creation paths, and the singleton-like behavior of the GlobalData structure, ensuring that cost attributes and initial states were correctly initialized. By introducing a new test script and integrating it into the codebase, the developer enhanced regression protection and clarified data contracts. This approach improved onboarding for new contributors and increased confidence in future changes, reflecting a methodical focus on testing and backend development best practices.