Worked on the JetBrainsRuntime repository to refactor cross-platform OS-specific tests, focusing on improving reliability and maintainability of the test suite. Utilized Java and platform-specific development skills to gate the PromiscuousIPv6 test to Linux and macOS using the @requires annotation, ensuring platform constraints were centralized and preserved. Extracted the Windows DOS hidden attributes test into a separate method, enhancing clarity and reducing code duplication. These changes streamlined the testing process, reduced cross-platform test flakiness, and accelerated CI feedback. The work also contributed to easier onboarding for new contributors and aligned with broader goals of reliability and development velocity.