SPA Mode | Remix
From the beginning, Remix's opinion has always been that you own your server architecture. This is why Remix is built on top of the Web Fetch API and can run on any modern runtime via built-in or community-provided adapters. While we believe that having a server provides the best UX/Performance/SEO/etc. for most apps, it is also undeniable that there exist plenty of valid use cases for a Single Page Application in the real world:
SPA Mode is basically what you'd get if you had your own React Router + Vite setup using createBrowserRouter/RouterProvider, but along with some extra Remix goodies:
File-based routing (or config-based via routes())
Automatic route-based code-splitting via route.lazy
<Link prefetch> support to eagerly prefetch route modules
<head> management via Remix <Meta>/<Links> APIs
SPA Mode tells Remix that you do not plan on running a Remix server at runtime and that you wish to generate a static index.html file at build time and you will only use Client Data APIs for data loading and mutations.
The index.html is generated from the HydrateFallback component in your root.tsx route. The initial "render" to generate the index.html will not include any routes deeper than root. This ensures that the index.html file can be served/hydrated for paths beyond / (i.e., /about) if you configure your CDN/server to do so.
React
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