Worked on the google/kotlin repository to deliver a feature that extends location information in compiler messages, enabling optional inclusion of end line and column numbers for improved diagnostics. The implementation introduced an extendedLocations setting, controlled via a system property, allowing developers to toggle enhanced message rendering as needed. Using Kotlin and focusing on compiler development and build tools, the work maintained backward compatibility while providing more precise error locations. All changes were documented with traceable commits, supporting clear visibility and integration into existing tooling. This approach improved the developer experience by reducing debugging time and enhancing the accuracy of diagnostic messages.