Remote Modules

Remote Modules Overview

Remote Modules is a building block you will reach for often in Module Federation. It keeps related logic together and makes your intent obvious to reviewers and future maintainers.

When you learn remote modules properly, you avoid the guesswork that leads to bugs and rework. The example below shows the shape you will use in most real Module Federation projects.

// remote (webpack.config.js)
const { ModuleFederationPlugin } = require('webpack').container;

module.exports = {
  plugins: [
    new ModuleFederationPlugin({
      name: 'catalog',
      filename: 'remoteEntry.js',
      exposes: {
        './ProductList': './src/ProductList',
      },
      shared: ['react', 'react-dom'],
    }),
  ],
};

A remote exposes modules through remoteEntry.js so hosts can load them at runtime.

Remote Modules Example

new ModuleFederationPlugin({
  name: 'app',
  filename: 'remoteEntry.js',
  exposes: { './Widget': './src/Widget' },
  remotes: { other: 'other@http://host/remoteEntry.js' },
  shared: { react: { singleton: true } },
});

• Start from a minimal Remote Modules example and grow it only as needed.
• Keep configuration explicit so Remote Modules behaves the same in every environment.
• Name things clearly so teammates understand your Remote Modules at a glance.
• Add tests around Remote Modules early to lock in expected behaviour.

Module Federation Cheatsheet

Key Module Federation settings related to remote modules.

How Remote Modules Works in Module Federation

Remote Modules builds on Module Federation's ability to load code from another independently built and deployed application at runtime. Each app can be a host, a remote, or both.

A remote exposes modules through remoteEntry.js so hosts can load them at runtime.

• Remotes expose modules through a remoteEntry.js manifest.
• Hosts declare remotes and import exposed modules dynamically.
• Shared dependencies are deduplicated, ideally as singletons.
• Each micro frontend builds and deploys on its own schedule.

Practical Guidance for Remote Modules

In production, remote modules needs careful version management and graceful failure handling. Align shared dependency versions and always render a fallback when a remote cannot load.

Common Mistakes

• Copying remote modules snippets without understanding what each line does.
• Skipping error handling and edge cases when wiring up remote modules.
• Leaving remote modules untested, so regressions slip into production.
• Over-engineering remote modules before you actually need the extra flexibility.

Key Takeaways

• Remote Modules is a core part of working effectively with Module Federation.
• Start small and keep remote modules focused on a single responsibility.
• Apply consistent patterns so remote modules scales across your project.
• Test and document remote modules to keep it maintainable over time.