Deep Linking

Deep Linking Overview

Deep Linking lets you structure Module Federation work so it stays readable, testable, and easy to scale. Instead of ad-hoc code, you follow a clear pattern that other developers can recognise immediately.

The key is to keep deep linking focused and predictable. Start from the minimal example here, then layer in only the complexity your feature actually needs.

const { ModuleFederationPlugin } = require('webpack').container;

module.exports = {
  plugins: [
    new ModuleFederationPlugin({
      name: 'shell',
      remotes: { catalog: 'catalog@http://localhost:3001/remoteEntry.js' },
      exposes: {},
      shared: { react: { singleton: true }, 'react-dom': { singleton: true } },
    }),
  ],
};

ModuleFederationPlugin configures which modules an app exposes, consumes, and shares.

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

Module Federation Cheatsheet

Key Module Federation settings related to deep linking.

How Deep Linking Works in Module Federation

Deep Linking 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.

ModuleFederationPlugin configures which modules an app exposes, consumes, and shares.

• 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 Deep Linking

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

Common Mistakes

• Skipping error handling and edge cases when wiring up deep linking.
• Leaving deep linking untested, so regressions slip into production.
• Over-engineering deep linking before you actually need the extra flexibility.
• Ignoring documentation, which makes deep linking hard for the next developer to change.

Key Takeaways

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