Middleware

Middleware runs before each render, in both fluixi dev and production. Define a chain in src/middleware.ts:

import { defineMiddleware } from '@fluixi/start';

export default defineMiddleware([
  async (request, next) => {
    if (!isAuthed(request)) {
      return new Response(null, { status: 302, headers: { location: '/login' } });
    }
    return next(); // continue the chain (ending in the renderer)
  },
]);

Each middleware gets a Web Request and a next(). It can short-circuit by returning a Response, or call next() and adjust the result (add headers, rewrite).

Interceptors

For the client side, addInterceptor wraps fetch (and server-function RPC) with a request/response/error pipeline — attach auth headers, refresh on 401, retry.

Next: Static generation.