Worked on the mixxxdj/mixxx repository to address a critical bug affecting the Pioneer DDJ-FLX4 controller’s hotcue state representation in MIDI configuration. Focused on controller integration and MIDI programming, the developer replaced obsolete hotcue status keys within XML configuration files to improve the accuracy and stability of hotcue state reporting. This targeted fix enhanced hardware compatibility and reduced mapping errors during live performances. The approach included thorough regression validation to ensure reliability across supported controllers. By delivering a precise, low-risk update, the developer reinforced user trust and contributed to the ongoing maintainability of controller mappings within the project’s codebase.