@exactjs/microfrontends

Federated microfrontend support for eXact hosts and remotes.

Overview

The package defines remote exposure and consumption configuration, shared-package policy, development discovery, build artifacts, client loading, SSR coordination, and root lifecycle. It integrates with the eXact build and server runtimes rather than replacing them.

Usage model

Keep host names, remote exposures, shared versions, and server gateways explicit. Load remote components from their compiler-produced artifacts, and keep page-authored child content owned by the page root. Configure each remote's integrity when its entry bytes must be verified before execution. The browser enforces that SRI pin through the generated module-entry loader; an unpinned entry is explicitly trusted executable authority. Replacement resolvers should return { clientEntry, integrity } for pinned build rotation. Remote entry waits stop with their owning component. Shared loads have a 30-second timeout and a 64-entry cache ceiling so stalled deployments cannot accumulate indefinitely. On SSR, RemoteComponent is emitted as a compiler-owned client boundary; its browser loader does not execute on the server. Page-authored children retain their page instances and lifecycle when a remote build or cross-root patch replaces the remote ancestor around them.

Server-executing remote builds may carry the compact component-library authorization identity created by @exactjs/component-library-policy. The remote entry, hydration client, gateway, and retained component host preserve that identity and reject a mismatched build before operation dispatch; full authorization and audit manifests remain server-private. For paired Vite builds, read the completed server manifest with readExactComponentAuthorizationIdentity() and pass the result as the eXact Vite plugin's componentAuthorization option while producing the remote artifact.

Vite/Rollup, Webpack 5, and Bun 1.3+ consume the same exposure plan. Webpack integration is owned by ExactWebpackPlugin; Bun remote producers call exactBuild() from @exactjs/bun-plugin so asynchronous plan preparation happens before Bun.build. Both adapters preserve actual emitted CSS, asset, and lazy-chunk locations, provided-package bootstrap order, and last-valid generation publication.

For architecture and deployment examples, see microfrontends.

Documentation | Source on GitHub