We built syntax highlighting in Warp's terminal input editor to improve user experience, specifically addressing issues with command entry, such as mistyped commands and lack of visual differentiation between command parts. We used a custom text editing library, Apple's Metal graphics library, to style text in-place within the input editor, utilizing a SumTree data structure for efficient text representation and manipulation. The parser was adapted from Nushell to support error underlining and syntax highlighting, with debouncing and short-circuit triggers implemented to prevent performance regressions and ensure instant styling updates when user interactions occur. After launching these features to all users, we received an exciting feedback, showcasing the impact one can have in such a role.