Bruno Tulio worked on the catppuccin/nix repository, focusing on improving the Fish shell theme’s configuration management. He implemented logic to default the Latte flavor to Mocha, providing a clear warning when Latte is explicitly selected, which clarified theme behavior and reduced user confusion. By aligning dynamic theming with Home Manager configurations, Bruno ensured consistent theme application across different environments. His work, primarily using Nix and configuration management skills, enhanced maintainability and streamlined onboarding for new users. Although the scope was limited to a single feature over one month, the changes addressed real user pain points and reduced support overhead for the project.