Worked on the sst/opentui repository to enhance the stability of a React-based terminal UI by addressing a crash related to destroyed renderables during lifecycle passes. Utilized TypeScript and front end development skills to guard the render loop against objects that had already been destroyed, preventing nondeterministic failures. Refactored the destruction sequence in TextBufferRenderable to ensure proper unregistration before freeing native resources, reducing the risk of race conditions. Developed a regression test to simulate the problematic scenario and confirm the fix, ensuring that all existing tests continued to pass. Focused on robust, maintainable code and comprehensive test coverage throughout.