Develops and reviews React, Next.js, TypeScript, Tailwind, and HTML/CSS web apps with strict coding standards and Web Vitals performance. Always use when the user mentions frontend, react, next.js, tailwind, css, html, javascript, typescript, components, state management, web vitals, server actions, gen-ui, RSC, or client-side work — even if they only ask to "fix this page", "refactor this component", or "make it faster".