asijs-vite — Vite 8 / Rolldown dev server for AsiJS

Run an AsiJS backend and a Vite frontend on a single port. AsiJS handles API routes, Vite handles the frontend (HMR, transforms) — no proxy juggling, no two terminals.

• Package: asijs-vite
• Status: released
• Source: packages/asijs-vite/

Why

Approach	Problem
Two servers + proxy	Two terminals, CORS, proxy config drift
asi dev only	Can't serve a Vite frontend with HMR
Vite-only	No AsiJS backend (validation, plugins, OpenAPI, WebSocket)

asijs-vite merges both: one vite dev process serves the SPA and the API.

Installation

bun add asijs-vite

Requires asijs and vite (>= 5; Vite 8 / Rolldown supported) as peer dependencies.

Quick Start

// vite.config.ts
import { defineConfig } from "vite";
import { Asi } from "asijs";
import { createVitePlugin } from "asijs-vite";

const app = new Asi();
app.get("/api/hello", () => ({ message: "Hello from AsiJS!" }));
app.get("/api/time", () => ({ time: new Date().toISOString() }));

export default defineConfig({
  plugins: [createVitePlugin(app, { apiPrefix: "/api", hmrBridge: true })],
});

bun run dev   # Vite serves the frontend on 5173, /api/* goes to AsiJS

Or scaffold a full starter:

bunx asijs create my-app -t vite-app

The vite-app template ships vite.config.ts, an index.html, a small frontend entry, and src/main.ts with the AsiJS app (/api/hello, /api/time).

API

Export	Description
createVitePlugin(app, opts?)	Vite plugin: wires the AsiJS middleware into configureServer / configurePreviewServer.
createViteHandler(app, opts?)	Plain (request) => Response handler (Vite middleware mode / custom wiring).
createViteMiddleware(app, opts?)	Connect-style middleware for server.middlewares.use(...) when wiring manually.
attachHmrBridge(server, app, opts?)	Forward AsiJS hot-reload events to Vite's WebSocket (full-reload).
ssrBuild(opts)	SSR bundle via Rolldown (Vite 8's bundler) when installed, falling back to Bun.build.

Options (AsijsViteOptions)

Option	Default	Description
apiPrefix	"/api"	Path prefix(es) routed to AsiJS; everything else falls through to Vite. Use an array (["/api", "/__dev"]) to also expose AsiJS dev routes (dashboard, OpenAPI, playground).
stripPrefix	false	Strip the prefix before handing the request to AsiJS (/api/users → /users).
hmrBridge	false	Watch AsiJS source and send full-reload to Vite clients on backend changes.
watchDirs	["src"]	Directories watched by the HMR bridge.
verbose	false	Request / error logging.
onError	500 JSON	Custom error handler.

How it works

createVitePlugin registers a Connect middleware at the front of Vite's middleware stack. Requests whose pathname matches apiPrefix are converted to a standard Request and passed to app.handle(); the Response is written back to the Node-style res. Everything else flows through to Vite's own middleware (HTML, modules, assets, HMR).

The request conversion is a plain Request (method, headers, buffered body, query string preserved) — so every AsiJS feature works unchanged inside Vite: validation, middleware, plugins, error pages, rate limiting.

HMR bridge

With hmrBridge: true, the plugin starts an AsiJS HotReloader over your source dir. When a backend handler or route changes, it pushes { type: "full-reload" } to Vite's WebSocket — the browser reloads without a manual refresh. The bridge uses AsiJS's own HotReloader (injected via options.hotReloader or imported from asijs); if neither is available it logs a warning and becomes a no-op.

SSR build

import { ssrBuild } from "asijs-vite";

const res = await ssrBuild({
  entry: "src/ssr.tsx",
  outDir: "dist-ssr",
  outFile: "index.js",
});
if (res.ok) console.log("SSR bundle at", res.outputPath, "via", res.engine);

Uses Rolldown (the bundler behind Vite 8) when it is installed, and falls back to Bun.build otherwise — res.engine reports which one ran.

Option	Default	Description
entry	—	Entry file (SSR server bundle, e.g. src/ssr.tsx).
outDir	"dist-ssr"	Output directory.
outFile	"index.js"	Output file name.
external	["asijs", "vite"]	Packages left as imports.
forceBun	false	Force Bun.build even when Rolldown is installed.
minify	false	Minify output.

Manual wiring (no plugin)

import { createVite } from "vite";
import { Asi } from "asijs";
import { createViteMiddleware } from "asijs-vite";

const app = new Asi();
app.get("/api/ping", () => ({ pong: true }));

const server = await createVite({ server: { middlewareMode: true } });
server.middlewares.use(createViteMiddleware(app));
await server.listen();

Development

cd packages/asijs-vite
npm install        # pulls asijs from the repo root (file:../..)
npm run typecheck  # tsc --noEmit
npm test           # bun test (16 tests)

Roadmap (TODO.md 3.5)

• [x] asijs-vite — AsiJS as dev server for Vite apps (single port, prefix routing)
• [x] HMR bridge — Vite HMR → AsiJS HMRServer (WebSocket)
• [x] Rolldown integration — AsiJS SSR bundle via Rolldown (faster than esbuild)
• [x] Example: asi create vite-app — AsiJS + Vite 8 template