Architecting the Migration:
jQuery→React

jQuery to React migration follows a component-first methodology. Phase one analyzes the existing jQuery codebase, identifying discrete functional areas that can become React components. We map jQuery selectors to component boundaries, event handlers to props and state, and AJAX calls to data fetching hooks. Phase two establishes the React infrastructure alongside the existing jQuery code. Using the component island pattern, we mount React components into specific DOM nodes while jQuery continues managing the surrounding page. This coexistence allows incremental migration without disrupting users. Phase three migrates functionality component by component, starting with isolated features that don't depend on other jQuery code. Each migrated component receives comprehensive tests. We use React Query or TanStack Query to handle data fetching, replacing jQuery AJAX patterns. Phase four addresses shared functionality... navigation, authentication, and global state. These cross-cutting concerns move to React Context providers or state management libraries. The jQuery-React boundary gradually moves until jQuery handles only the diminishing legacy portions. Phase five completes the migration, removing jQuery entirely. We optimize the React application with code splitting, lazy loading, and potentially Server Components if using Next.js. The final application is a modern, maintainable React codebase.

The React Advantage

jQuery to React migration delivers ROI through developer productivity, performance, and maintainability. Teams report 40-60% faster feature development in React compared to jQuery... the component model enables reuse and the unidirectional data flow simplifies debugging. Performance improvements range from 40-60% for complex interactive UIs. React's virtual DOM eliminates redundant DOM operations that jQuery code accumulates over time. For e-commerce sites, this directly impacts conversion rates... a 1-second improvement in interactivity correlates with 7% conversion lift. Code quality improves dramatically with TypeScript integration and component-based architecture. Bugs that took hours to trace through jQuery callback chains become immediately apparent in React's predictable data flow. Test coverage becomes practical where it was previously prohibitive. Hiring and retention improve as developers prefer working with modern tools. React developers are abundant and enthusiastic; jQuery maintenance roles are difficult to fill and suffer higher turnover. The total cost of ownership for a React application is typically 25-35% lower than equivalent jQuery functionality over 3 years.