Developed the Screen Wake Lock Persistence feature for voice conversations in the elevenlabs/packages repository, addressing the need to keep the screen active during calls even as app visibility changes. Leveraging TypeScript and front end development skills, implemented a persistent wake lock mechanism tied to the session lifecycle and visibility transitions, ensuring uninterrupted user experience throughout voice conversations. Added comprehensive tests to cover session start, end, and visibility changes, and performed codebase cleanup by removing test-only flags to guarantee full test coverage. This work improved call reliability and user engagement, demonstrating a methodical approach to both feature delivery and testing.