CDN Deployment

CDN Deployment sits at the heart of deployment in Module Federation. This guide walks through the concept step by step, with examples, a cheatsheet, and common mistakes to avoid.

CDN Deployment Overview

CDN Deployment 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 cdn deployment focused and predictable. Start from the minimal example here, then layer in only the complexity your feature actually needs.

# each micro frontend deploys independently
catalog:  https://cdn.example.com/catalog/remoteEntry.js
checkout: https://cdn.example.com/checkout/remoteEntry.js

# the host resolves remotes from a runtime manifest
{ "catalog": "https://cdn.example.com/catalog/remoteEntry.js" }

Independent deployment is the core benefit: each remote ships on its own schedule.

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

Module Federation Cheatsheet

Key Module Federation settings related to cdn deployment.

Option	Example	Purpose
name	`name: 'shell'`	Unique container name
filename	`filename: 'remoteEntry.js'`	Remote entry manifest
exposes	`exposes: { './X': './src/X' }`	Modules a remote shares
remotes	`remotes: { app: 'app@url' }`	Remotes a host consumes
shared	`shared: { react: { singleton: true } }`	Deduplicate libraries
lazy load	`import('remote/Module')`	Load remotes on demand
Suspense	`<Suspense fallback={...}>`	Handle async loading

How CDN Deployment Works in Module Federation

CDN Deployment 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.

Independent deployment is the core benefit: each remote ships on its own schedule.

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 CDN Deployment

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

Concern	Recommendation
Shared versions	Use singletons with requiredVersion
Runtime errors	Wrap remotes in error boundaries and fallbacks
Deployment	Resolve remotes from a runtime manifest
Performance	Lazy-load remotes and cache remoteEntry.js

Common Mistakes

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

Key Takeaways

CDN Deployment is a core part of working effectively with Module Federation.
Start small and keep cdn deployment focused on a single responsibility.
Apply consistent patterns so cdn deployment scales across your project.
Test and document cdn deployment to keep it maintainable over time.

Pro Tip

When you get stuck on cdn deployment, reduce it to the smallest reproducible example first — most Module Federation issues become obvious once the noise is gone.