Microfrontends in Large-Scale Projects: From Design to Deployment with Module Federation

As front-end applications continue to grow in size and complexity, traditional monolithic architectures often struggle to scale efficiently. Teams end up wrestling with slow builds, tightly coupled dependencies, and fragile deployments. Microfrontends emerged as a natural evolution—bringing the principles of microservices to the front end.

A microfrontend architecture breaks down a web application into smaller, autonomous, independently deployable frontend modules, each owned by a different team or domain. This enables parallel development, isolated deployments, and long-term scalability.

With the introduction of Webpack 5’s Module Federation, microfrontends became significantly easier to implement—without needing complex runtime orchestration or custom bundling pipelines.

In this article, we’ll explore the design principles behind microfrontends, understand how Module Federation enables them, and walk through an example of how to design, build, and deploy a modular frontend architecture at scale.

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1. The Need for Microfrontends

In large organizations, multiple teams often collaborate on a single frontend application—each focusing on a feature area such as authentication, dashboard analytics, or payments.

Traditional SPA architectures introduce bottlenecks:

• Shared build pipelines cause long CI/CD times.
• Global dependencies lead to version conflicts.
• Deployment of one feature may break another.
• Teams cannot deploy independently.

Microfrontends solve this by decoupling ownership: each team manages its codebase, deployment lifecycle, and release cadence. Instead of one massive React or Angular app, you end up with multiple smaller frontends, seamlessly composed at runtime.

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2. Core Principles of Microfrontend Architecture

Before diving into implementation, it’s important to understand the core principles guiding microfrontends:

1. Decentralization of code and ownership Each microfrontend is self-contained with its own repository, CI/CD pipeline, and release version.
2. Technology agnosticism While frameworks should ideally be consistent, microfrontends allow teams to evolve independently (React, Vue, Svelte, etc.)—though cross-framework interoperability requires careful design.
3. Independent deployment Teams can deploy without coordinating with others, as long as integration contracts remain stable.
4. Runtime composition The app should dynamically compose microfrontends at runtime—through Module Federation, iFrames, or server-side composition.
5. Consistent UX and communication Even though teams work independently, the application must look and behave as one cohesive product—requiring shared design systems and event buses.

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3. Enter Module Federation

Before Webpack 5, microfrontends were implemented using hacks—embedding iframes, dynamically loading bundles, or relying on build-time integrations.

Module Federation, introduced in Webpack 5, changed everything.

It allows JavaScript applications to dynamically import code from other independently deployed builds at runtime.

This means one app (the “host”) can consume components, utilities, or even entire microfrontends from another app (the “remote”) without rebuilding or redeploying.

Example Configuration

Host (Shell App):

// webpack.config.js
new ModuleFederationPlugin({
  name: 'shell',
  remotes: {
    dashboard: 'dashboard@https://dashboard-app.com/remoteEntry.js',
  },
  shared: ['react', 'react-dom'],
});

Remote (Dashboard App):

// webpack.config.js
new ModuleFederationPlugin({
  name: 'dashboard',
  filename: 'remoteEntry.js',
  exposes: {
    './DashboardPage': './src/pages/DashboardPage',
  },
  shared: ['react', 'react-dom'],
});

At runtime, the Shell app can load the remote dashboard like this:

import React from 'react';

const DashboardPage = React.lazy(() => import('dashboard/DashboardPage'));

function App() {
  return (
    <React.Suspense fallback={<p>Loading Dashboard...</p>}>
      <DashboardPage />
    </React.Suspense>
  );
}

This is runtime composition in action—React components are fetched and executed from a remote deployment dynamically.

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4. Architectural Patterns for Microfrontends

There are multiple ways to structure a microfrontend ecosystem. The most common are:

a. Vertical Split (Feature-Based)

Each domain feature is its own microfrontend:

• /auth
• /dashboard
• /payments

This is the simplest and most maintainable pattern.

b. Horizontal Split (Layer-Based)

Each layer (e.g., layout shell, navigation, footer, content areas) is a separate microfrontend.

This is common in platforms where the shell dynamically orchestrates multiple remotes.

c. Hybrid Composition

A hybrid model combines both vertical and horizontal splits—commonly used in enterprise-scale applications like e-commerce or admin portals.

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5. Design Considerations

Implementing microfrontends requires thoughtful architectural planning:

🧱 Shared Libraries

Decide how dependencies (React, Redux, design system) are shared:

• Use Module Federation shared scope to avoid code duplication.
• Pin versions of shared packages to prevent mismatches.

🎨 Consistent UI/UX

Create a shared design system or component library that each microfrontend consumes.

Example: @company/ui-kit.

🔄 Inter-MFE Communication

Microfrontends should communicate through:

• A global event bus (e.g., RxJS, tiny-emitter)
• A shared state layer (like Redux Toolkit Query or Zustand)
• URL-based state (query params, route changes)

🚀 Deployment Strategy

Each microfrontend should have its own CI/CD pipeline but deploy to a common environment:

• shell.company.com (host)
• dashboard.company.com
• auth.company.com

The host dynamically references each remote’s URL—decoupling deployments.

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6. Example: Building a Modular Dashboard with Module Federation

Let’s illustrate this with a realistic setup: a modular analytics dashboard for a SaaS platform.

Project Structure

/shell
  webpack.config.js
/dashboard
  webpack.config.js
/auth
  webpack.config.js

Each app is its own repository or submodule.

The Shell

The Shell is responsible for layout, routing, and orchestrating remote components.

// Shell webpack.config.js
new ModuleFederationPlugin({
  name: 'shell',
  remotes: {
    dashboard: 'dashboard@https://cdn.company.com/dashboard/remoteEntry.js',
    auth: 'auth@https://cdn.company.com/auth/remoteEntry.js',
  },
  shared: ['react', 'react-dom', 'react-router-dom'],
});

The Dashboard App

// Dashboard webpack.config.js
new ModuleFederationPlugin({
  name: 'dashboard',
  filename: 'remoteEntry.js',
  exposes: {
    './Widget': './src/components/Widget',
  },
  shared: ['react', 'react-dom'],
});

The Auth App

// Auth webpack.config.js
new ModuleFederationPlugin({
  name: 'auth',
  filename: 'remoteEntry.js',
  exposes: {
    './LoginForm': './src/components/LoginForm',
  },
  shared: ['react', 'react-dom'],
});

The Shell Consuming Remotes

import React, { Suspense } from 'react';
import { BrowserRouter, Routes, Route } from 'react-router-dom';

const Dashboard = React.lazy(() => import('dashboard/Widget'));
const LoginForm = React.lazy(() => import('auth/LoginForm'));

export default function App() {
  return (
    <BrowserRouter>
      <Suspense fallback={<p>Loading...</p>}>
        <Routes>
          <Route path="/dashboard" element={<Dashboard />} />
          <Route path="/login" element={<LoginForm />} />
        </Routes>
      </Suspense>
    </BrowserRouter>
  );
}

Now each app is deployed independently. When a user visits /dashboard, the host shell fetches the dashboard microfrontend directly from its CDN.

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7. Deployment and Versioning

A robust deployment strategy is critical.

To achieve seamless updates:

• Use semantic versioning for each remote.
• Host remotes on a CDN with immutable URLs (e.g., v1.3.0/remoteEntry.js).
• The host fetches the latest stable version via a configuration service or environment variables.

For zero-downtime rollouts:

1. Deploy the new remote version.
2. Update the configuration in the host.
3. Verify integration using feature flags.

This enables safe, independent, and reversible deployments across teams.

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8. Common Pitfalls and How to Avoid Them

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9. Beyond Module Federation: Alternative Approaches

While Module Federation is the most popular and modern approach, others exist:

• Single-SPA: Orchestrates multiple frontends at runtime via routing.
• Web Components: Encapsulate logic in framework-agnostic components.
• Edge Composition: Compose microfrontends on the CDN edge before serving.

In many enterprise cases, Module Federation is the best balance of flexibility and performance, but combining it with edge or server composition can further optimize latency and reliability.

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10. Real-World Use Cases

Major companies successfully use microfrontends to scale large applications:

• Spotify – Independent microfrontends for playlists, user profiles, and search.
• Zalando – Microfrontends across multiple teams and deployment pipelines.
• DAZN – Module Federation for their video streaming dashboards.
• Shopify – Modular architecture for their admin and storefront tools.

These examples show that microfrontends aren’t just a theoretical idea—they’re a proven solution for large-scale engineering teams.

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11. Key Takeaways

• Microfrontends bring modularity, scalability, and autonomy to frontend teams.
• Module Federation enables dynamic runtime composition without build coupling.
• Each microfrontend should own its code, CI/CD, and deployment.
• Focus on shared libraries, consistent design systems, and inter-MFE communication.
• Design for observability, versioning, and rollback safety.

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12. Conclusion

Microfrontends, empowered by Module Federation, mark a major shift in frontend architecture.

They turn sprawling monolithic apps into distributed systems of independent frontends, each with its own lifecycle but a unified user experience.

By embracing this approach, organizations can accelerate development, reduce dependencies between teams, and scale confidently as applications evolve.

In the end, microfrontends are not just about technology—they’re about empowering teams to build and deploy at the speed of innovation.