Multi-Tenant Runtime Isolation

Use runtimeKey when one shell hosts multiple tenants, experiments, or isolated runtime scopes on the same page. The key partitions manifest caches, pending manifest requests, circuit breaker state, registered manifest remote debug records, and remote load metrics.

Scoped Runtime API

createFederationRuntimeScope(runtimeKey) returns wrappers that automatically pass the same runtimeKey to manifest runtime APIs.

import { createFederationRuntimeScope } from 'vite-plugin-federation/runtime';

const tenantA = createFederationRuntimeScope('tenant-a');
const tenantB = createFederationRuntimeScope('tenant-b');

await tenantA.registerManifestRemote('catalog', tenantAManifestUrl, {
  shareScope: 'tenant-a',
});

await tenantB.registerManifestRemote('catalog', tenantBManifestUrl, {
  shareScope: 'tenant-b',
});

The scoped object exposes:

• fetchFederationManifest
• registerManifestRemote
• loadRemoteFromManifest
• refreshRemote
• warmFederationRemotes
• getFederationDebugInfo

Cache And Circuit Breaker Isolation

The same manifest URL can be fetched independently by multiple runtime keys:

await tenantA.fetchFederationManifest(manifestUrl, { cacheTtl: 30_000 });
await tenantB.fetchFederationManifest(manifestUrl, { cacheTtl: 30_000 });

Each tenant gets its own cache entry and circuit breaker state, so one tenant's failing rollout does not poison another tenant's manifest cache.

Share Scopes And Aliases

Use tenant-specific shareScope values when tenants may provide different singleton/shared versions. runtimeKey isolates plugin-side manifest state and diagnostics; the underlying Module Federation runtime still needs remote aliases to be unambiguous for actual module requests. If two tenants must load different implementations at the same time, prefer tenant-specific request aliases such as tenantACatalog and tenantBCatalog, or route requests through a tenant-aware runtime scope.

Debugging

Global debug snapshots include runtimeKey on manifest cache entries, fetch history, circuit breakers, registered manifest remotes, last load errors, and remote load metrics.

console.table(tenantA.getFederationDebugInfo().runtime.manifestCache);
console.table(tenantA.getFederationDebugInfo().runtime.remoteLoadMetrics);

Use scoped debug snapshots when sending tenant-specific telemetry so unrelated tenants do not leak into logs.