The CARTO.js 4.0 beta release provides an updated JavaScript library for creating custom UI components, such as widgets and pop-ups, with enhanced data extraction and filtering capabilities. The new version allows developers to build visually stunning and functional applications using location intelligence tools. A recent internal hackathon showcased the library's potential by demonstrating various use cases, including displaying US wildfires, exploring regional patterns in place names, and visualizing bike ride intensity. The CARTO.js 4.0 beta release includes changes to the JavaScript library only, with a future enhancement planned for core application maintenance.