Runtime

@softarc/native-federation-runtime — the browser-side library that reads remoteEntry.json files, merges them into one import map, and resolves loadRemoteModule() calls against it.

@softarc/native-federation-runtime is the host-side half of Native Federation v3. The core builder writes a remoteEntry.json per application; the runtime reads them in the browser, merges them into a single ES module import map, injects it into the DOM, and resolves loadRemoteModule() calls against it.

It is deliberately small. Two functions cover the common case:

import { initFederation, loadRemoteModule } from '@softarc/native-federation-runtime';

// once, before the app bootstraps
await initFederation({ mfe1: 'http://localhost:3001/remoteEntry.json' });

// wherever a remote is needed
const { AppComponent } = await loadRemoteModule('mfe1', './Component');

Angular projects get the same surface from @angular-architects/native-federation, whose main entry is a single export * from '@softarc/native-federation-runtime' — see Angular Adapter → Runtime.

What it does at startup

1. Fetches the host's own remoteEntry.json and turns its shared[] into root-level import-map entries.
2. Fetches every configured remote's remoteEntry.json in parallel, adding each remote's exposed modules to the root imports and its shared deps to a scope keyed by the remote's base URL.
3. Deduplicates shared dependencies through an in-memory externals registry keyed by packageName@version — an exact match, not a semver range.
4. Injects the merged map as <script type="importmap-shim">, behind a Trusted Types policy when the page enforces one.

State lives on globalThis.__NATIVE_FEDERATION__ — the externals registry plus two maps of registered remotes. Because it hangs off the global object, a second copy of the runtime on the same page shares the same registries rather than starting over.

Pages

• Getting Started — install, es-module-shims, the bootstrap split, first remote.
• initFederation — inline remotes vs manifest, deployUrl, cacheTag, error behaviour, hot reload.
• loadRemoteModule — both call forms, lazy registration, fallbacks.
• The Import Map — root imports, scopes, the externals registry, Trusted Types.
• API Reference — every export, the global cache, the Module Federation bridge.

Do you want the orchestrator instead?

@softarc/native-federation-orchestrator is the v4 runtime, and it speaks the same remoteEntry.json contract — so it can load v3-built remotes. It is an opt-in on the v3 line: worth it if you need semver-range resolution across remotes that disagree on a version, share scopes, or persistent caching of remoteEntry.json between page loads. See Orchestrator for what it adds and how to adopt it, and Migration to v4 if you are moving the whole stack.