A LESS pre-processor developer utilizes the LESS scripting language to enhance CSS stylesheets. They create reusable, maintainable, and extendable CSS codes using features like variables, mixins, functions, and operations. They compile LESS code into browser-readable CSS, ensuring the website’s design is consistent across different web browsers. They also debug and fix issues in the CSS code, optimize the code for better performance, and maintain the codebase. Their role involves collaborating with other developers and designers to ensure the visual elements of a website align with its functionality, thereby enhancing the overall user experience.