Developed a new theming capability for the zed-industries/extensions repository by delivering the Tbilisi Night Theme Extension, which introduced three cohesive variants to enhance UI customization. The work focused on maintainable front end development and theme design, utilizing JSON and TOML to ensure proper packaging, validation, and discoverability within the project structure. The extension was ported from an existing VS Code theme, with careful attention to licensing and attribution. Collaboration was emphasized through alignment of theme assets and schema compliance, laying a foundation for future extensibility. This contribution expanded the repository’s customization options while maintaining high standards for quality and structure.