what is module federation

What is Module Federation

Module Federation is a way for separate JavaScript apps to share code at runtime instead of bundling everything into one build. In practice, it lets one app load components, utilities, or even entire features from another independently deployed app.

Quick scoop

Think of it like a storefront mall instead of one giant department store: each shop can open, update, and stock its own shelves, while the mall still feels like one place to visitors.

How it works

• Each application can expose modules for others to use.

• Another app can consume those modules dynamically when the page runs.

• Shared dependencies, like React, can be loaded once and reused across apps.

• Teams can deploy parts of a product separately without waiting for a full monolith release.

Why people use it

• Faster independent releases.
• Better separation for large teams.
• A natural fit for micro-frontends.
• Less duplication of shared libraries at runtime.

What is changing now

Module Federation started as a webpack feature, but by early 2026 it had expanded into a broader cross-bundler approach through Module Federation 2.0, with support and ecosystem work around tools like Vite, Rollup, and Rspack. The official project also highlights recent work such as shared dependency tree shaking and improved integration tooling.

Practical tradeoffs

It is powerful, but it adds architectural complexity, especially around version compatibility and coordination between teams. It is usually best for larger systems where independent deployment matters more than simplicity.

TL;DR

Module Federation lets separate apps share and load code dynamically, making it a strong pattern for micro-frontends and independently deployable teams.