Federation vs. iframe

whisker-host implements both integration paths simultaneously. A single deployment can host a mix of federation modules and iframe consumers, and a single module team can move between them by changing one field in their manifest.

	Federation module	Iframe consumer
Use when	Greenfield, or rewrite	You already have a working app and just want it inside the host
Built with	Vite + Module Federation	Whatever you already use (React, Angular, anything)
Talks to host via	Direct ESM imports from remoteSafeSelectors.ts (useAuth, authService, useInEditMode, useIsNavOpen)	postMessage (T.R.U.E-compatible protocol)
Routing	Inside host’s BrowserRouter — useParams, useNavigate, Link all work natively	Owns its own router; host mounts a catch-all route
Auth token acquired	useAuth().accessToken	requestAccessToken message → host responds with accessToken
Style/theme	Imports Nike theme from the component library	Owns its own
Best for new code	Yes	Last resort; convert when you can

Scaffolding each path

# Federation module (greenfield)
thundercats create module my-module

# Convert an existing app to an iframe consumer
thundercats add iframe-consumer

Runtime flow

Both module types share one registry and one auth flow. The only difference is the rendering primitive (federated component vs <iframe>). See WhiskerPlatform Architecture for the full sequence diagram, from manifest fetch through token exchange.

See Architecture → Host ↔ module contract for the full mechanism, and Architecture → Consumer integration guide for onboarding an external team end to end.