Jin Hwang developed an interactive arrow highlighting feature for the CSE Machine in the source-academy/frontend repository, focusing on enhancing visualization for algorithm education. Using React and TypeScript, Jin refactored the arrow state management to allow persistent highlights and improved the selection logic for better UI performance. The update introduced color-coding to increase visibility and accessibility of selection states, making the interface more intuitive for users. Jin also addressed code quality by updating linting, cleaning up extraneous whitespace, and maintaining test snapshots. This work streamlined the codebase, reduced maintenance overhead, and improved the overall user experience for front end interactions.