React Architecture: Structuring Applications for Scalability

As React applications grow, architectural decisions become increasingly important. A clear structure improves maintainability, reduces cognitive load, and enables teams to collaborate effectively. Good architecture is not about rigid rules—it’s about consistent patterns that scale with your project.

Why Architecture Matters in React

React itself is unopinionated. This is a strength, but it also means developers must define their own conventions.

A well‑designed architecture provides:

• Predictability
• Separation of concerns
• Ease of navigation
• Scalability for teams and features
• Reduced duplication

Without structure, even small applications can become difficult to maintain.

Common Folder Structures

There is no single “correct” structure, but several patterns have emerged in professional React codebases.

Feature‑Based Structure

src/
  features/
    auth/
      components/
      hooks/
      pages/
      services/
    dashboard/
      components/
      hooks/
      pages/
  shared/
    components/
    hooks/
    utils/

Benefits

• Groups related logic
• Scales well for large teams
• Encourages modular design

Component Categories

React components often fall into several conceptual groups.

Presentational Components

Focused on UI, layout, and styling.

Container Components

Handle data fetching, state, and logic.

Page Components

Represent full screens or routes.

Shared Components

Reusable UI elements used across features.

This separation keeps responsibilities clear and reduces coupling.

Separation of Concerns with Hooks

Custom hooks allow you to extract logic from components, improving readability and reusability.

Example:

function useFetch(url) {
  const [data, setData] = useState(null);

  useEffect(() => {
    async function load() {
      const res = await fetch(url);
      setData(await res.json());
    }
    load();
  }, [url]);

  return data;
}

This pattern keeps components focused on rendering, not data management.

Service Layers

For complex applications, it’s helpful to isolate API calls and business logic.

Example structure:

src/
  services/
    userService.js
    authService.js

This avoids scattering fetch calls across components and centralizes error handling.

State Management Architecture

As applications grow, state often needs to be shared across multiple features.

Common approaches include:

• Local state with hooks
• Context for global configuration
• Reducers for complex flows
• External libraries (Redux, Zustand, Jotai) for large‑scale state

Choosing the right tool depends on the complexity of your data and the size of your team.

Styling Architecture

Styling can follow several patterns:

• CSS Modules
• Styled Components
• Tailwind CSS
• Component‑scoped styles

The key is consistency. Mixing multiple styling paradigms without intention leads to fragmentation.

Testing Strategy

A scalable architecture includes a clear testing approach.

Recommended layers:

• Unit tests for pure functions and hooks
• Component tests for UI behavior
• Integration tests for flows
• End‑to‑end tests for full user journeys

Testing ensures stability as the codebase evolves.

Why Architecture Shapes Success

A thoughtful architecture:

• Reduces onboarding time
• Prevents duplication
• Supports long‑term maintainability
• Enables parallel development
• Improves clarity and confidence

React’s flexibility is a strength, but only when paired with intentional structure.

Sources & Further Reading

• React Project Structure Guide: https://react.dev/learn/thinking-in-react
• Scalable Architecture Patterns: https://kentcdodds.com/blog/application-state-management
• React Testing Library: https://testing-library.com/docs/react-testing-library/intro/