Read, Think and Code

Thoughts on Module Federation 2.0

As someone who’s worked extensively with Module Federation 1.0, I can say it’s been an incredible tool for sharing modules and enabling micro-frontends. With it, we could split large applications into manageable, collaborative parts, allowing different teams to develop independently while still sharing components seamlessly. But, as with any first version, there were a few sticking points. Module Federation 2.0 aims to tackle these head-on, and as a programmer who’s used version 1.0 in production, I’m genuinely excited about what 2.0 brings to the table.

Let’s talk about why Module Federation 2.0 isn’t just an upgrade but a game-changer for modular development.

Why Use Module Federation 2.0?

Module Federation 1.0 was groundbreaking for a few key reasons: it enabled different applications to pull in shared modules directly at runtime, making it possible to develop isolated micro-frontends while sharing dependencies across the board. However, as we scaled, a few limitations emerged. Now, Module Federation 2.0 addresses these issues with enhanced flexibility, type safety, and new tools for debugging and deployment. Here are the highlights that I’m most excited about.

Decoupling the Runtime from Build Tools

In Module Federation 1.0, the Runtime was tightly coupled to Webpack, which made sense at the time, but limited flexibility when using other build tools. In 2.0, the Runtime has been separated into its own SDK, which means you’re no longer locked into Webpack. This new architecture lets developers use Module Federation with a variety of build tools, not just Webpack—tools like Rspack, and potentially even others down the line.

For me, this decoupling represents a major shift. It opens the door for experimenting with different build tools, optimizing for specific project needs, or integrating Module Federation into more complex build setups. Having a unified, standalone Runtime SDK also means that I can work with projects built on different stacks and easily share modules across them, which is huge for micro-frontends.

Type Safety with Dynamic Type Hints

In 1.0, working with TypeScript in a Module Federation setup was functional, but far from ideal. We were constantly juggling types, especially when dealing with dynamically imported modules. The pain was real: TypeScript often couldn’t infer the types for these remote modules, so we had to create manual type definitions or lose out on type safety.

Module Federation 2.0 has taken a big leap forward by dynamically generating type hints for remote modules in TypeScript projects. Now, the Runtime can automatically load types and sync them, similar to the experience you get with npm link. This means that type updates are reflected in real-time across all locally running projects. For developers like me who rely on TypeScript, this feature alone is worth the upgrade—no more guessing types or manually maintaining them.

Enhanced Debugging with Chrome DevTools

One of the frustrations in Module Federation 1.0 was debugging dependencies and shared modules. Figuring out why a module wasn’t loading or why there was a version conflict often meant going through Webpack output or logs line by line. With Module Federation 2.0, we now have a Chrome DevTools extension specifically for debugging federated modules.

The new DevTools extension provides a visual overview of dependencies, exposing and sharing configurations, and even allows proxying modules from live environments into your local setup for testing. It supports hot updates, making it easier to see how changes affect shared modules in real time. This kind of tooling simplifies troubleshooting and gives me more confidence when making updates, especially in large projects where multiple teams are contributing modules.

Flexible Module Loading and Preloading

Module Federation 1.0 was amazing for pulling in modules as needed, but managing preloading required some tricky setups. Version 2.0 has introduced a more robust module loading system, allowing us to dynamically register and load modules without relying on specific build tools. Preloading is now baked in, and with the new Runtime SDK, we have much finer control over when and how modules are loaded.

Here’s a quick example:

import { init, loadRemote } from '@module-federation/enhanced/runtime';

init({
  name: '@demo/app-main',
  remotes: [
    {
      name: "@demo/app1",
      entry: "http://localhost:3005/mf-manifest.json",
      alias: "app1"
    },
    {
      name: "@demo/app2",
      entry: "http://localhost:3006/remoteEntry.js",
      alias: "app2"
    },
  ],
});

loadRemote("app2/util").then((md) => {
  md.add(1, 2, 3);
});

This ability to dynamically register modules makes Module Federation more flexible and efficient. For example, I can now preload only the modules I know users will need in their current session, optimizing load times and improving performance across the board.

New Manifest Protocol for Deployment

Version management and deployment were challenging in 1.0, especially when multiple teams were deploying changes to the same remote module. Module Federation 2.0 introduces the mf-manifest.json protocol, which serves as a central source of truth for shared modules. This manifest file contains information about remoteEntry, shared, exposes, remotes, chunks, and types.

Using this manifest protocol, deployment platforms can now manage versions with precision, simplifying the handling of complex dependencies. In practice, this should make deploying new versions and managing “gray releases” (controlled rollouts) much easier, particularly in environments with multiple services or micro-frontends.

Future Plans: What’s Next?

Module Federation 2.0 has already set a new standard for module sharing and micro-frontends, but it looks like there’s more to come. Here are a few future features on the roadmap that I’m excited about:

  • Improved Developer Experience: Although we already have type hints and Chrome DevTools, there’s still room for more. Plans to add visualization for shared reuse in DevTools would make it even easier to understand how modules interact, improving collaboration and transparency.
  • High-Performance Solutions: Module Federation 2.0 plans to address the “request waterfall” issue that can impact performance in micro-frontends. Techniques like Server-Side Rendering (SSR) and data prefetching are on the horizon, which should reduce load times and optimize module loading.
  • Community and Compatibility: Currently, Module Federation 2.0 is fully compatible with Webpack and Rspack, and with the SDK, it’s primed for further expansion. As more build tools adopt this standard, I’m excited to see how the community will integrate Module Federation into their workflows and create best practices for micro-frontend architectures.

Final Thoughts

Module Federation 2.0 feels like a leap forward for anyone working in a large-scale modular architecture. The enhancements in type safety, debugging, module loading, and deployment make it a powerful solution for scaling applications without being locked into a single build tool. For teams building micro-frontends or modular apps, it’s hard to imagine a better way to manage shared modules, dependencies, and development workflows.

With these new tools, I’m looking forward to a development process that’s more efficient, type-safe, and flexible. Module Federation 2.0 isn’t just an upgrade—it’s a toolkit that’s paving the way for the next generation of web architecture.