Worked on expanding test coverage and robustness for the V2 User Sharing API in the wso2/product-is repository, focusing on integration tests that addressed failure scenarios, mode validation, and error handling. Used Java and REST Assured to implement and stabilize tests, ensuring early detection of regressions and improving reliability. Addressed intermittent test flakiness by refining assertion logic and awaitility retries, and updated documentation to align with the NONE mode behavior. Enabled backward-compatibility coverage by adding v1 user sharing failure integration tests. The work emphasized backend development and integration testing, resulting in more reliable and maintainable API test suites.