Worked on the Metrolist repository to deliver a cache-enabled lyrics data retrieval flow, focusing on improving both performance and data accuracy. Developed a new caching API in Kotlin to optimize backend interactions, reducing dependency on external LyricsPlus APIs and enhancing overall system reliability. Strengthened ISRC validation within the lyrics feature to ensure that requests for lyrics data were accurate and aligned with actual values, minimizing the risk of incorrect lyric fetches. The work emphasized robust API integration and backend development practices, maintaining clear change tracking in the repository to support future auditing and iterative improvements throughout the development process.