vite-plugin-nucleus

Build, serve and preview a Nucleus Stack site with one Vite plugin: pages, Quark modules and the service worker are found by convention, and the preview answers as your host does.

Features

• One line of config plugins: [nucleus()] covers vite, vite build and vite preview
• Conventions, not entry lists Root *.html files are pages, *.ts files are Quark @use modules, the service worker is bundled
• Host-true preview vite preview answers as Cloudflare Workers static assets do: _redirects, _headers, the 404 page
• Kit from a CDN kit: "unpkg" loads the NucleusKit from unpkg in a deploy build instead of bundling it
• CSS chain included @import / @import-glob, mixins, custom selectors and preset-env; nesting and light-dark() shipped as written
• Prerender-ready Builds what nucleus-ssr prerenders, and serves it for browser checks

Installation

Usage

Add the plugin to vite.config.js; vite, vite build and vite preview need nothing else. It runs on Vite 8.3 and Node 24.13, or later.

// vite.config.js
import { nucleus } from "@excom/vite-plugin-nucleus";

export default {
  plugins: [nucleus()], // a deploy build: nucleus({ kit: "unpkg" })
};

Conventions

What the project holds decides what is built:

index.html                              a page, as every *.html at the root
shell.ts                                a Quark module, built to /shell.js
public/
  _redirects                            /shell /shell.js 200
  views/cart/cart.ts                    a Quark module, built to /views/cart/cart.js
  service-worker/service-worker.js      bundled into one classic script

• Every *.ts at the root and under publicDir is a Quark module, built unhashed at its URL: keep other TypeScript in a folder of the root. Declarations, *.config.ts, *.test.ts and *.spec.ts are left alone
• An extensionless module URL (@use "/shell") needs its 200 line in _redirects, in dev as on the host
• The files the service worker imports are left out of the build unless a page or sheet names them. Dev sends Service-Worker-Allowed: / with the worker; on the host that is a line of your _headers
• Two files that would answer at one URL stop the build

The kit

A page loads the kit from a module script: import "@excom/nucleus-kit/nucleus-kit.progressive";. That path resolves from the first NucleusKit release after 0.3.0; with 0.3.0 write …/nucleus-kit.progressive.min, which works in both modes.

• kit: "bundled" (default) Vite bundles the kit like any dependency
• kit: "unpkg" vite build loads it from unpkg at the installed version, so the kit must be installed in the app. Imports of @excom/nucleus-kit/<entry> in a script and of @excom/nucleus-kit/<name>.css in a stylesheet are rewritten; the bare @excom/nucleus-kit is not. The build stops when kit code would ship, or on a path the kit does not export

What the plugin sets

• Set by the plugin The build's inputs and output file names, css.postcss, css.lightningcss.exclude (the minifier leaves light-dark() alone: Valence declares color-scheme in its own stylesheet, and a lowered light-dark() only works in a sheet that declares it itself) and, with kit: "unpkg", build.modulePreload: { polyfill: false }. A PostCSS config file is not read: add plugins in css.postcss.plugins
• Yours publicDir, build.outDir, build.emptyOutDir (default true) and build.assetsDir
• Not supported base: the site is served from /

Dev / preview

• vite applies the 200 lines of _redirects and answers any other unknown route with index.html. The site is read once per start: a new page or module needs a restart
• vite preview serves the build as Cloudflare Workers static assets do: _redirects, _headers (without Cache-Control and Strict-Transport-Security) and the assets options not_found_handling / html_handling of the nearest wrangler.jsonc or wrangler.json whose assets.directory is the build. What it does not emulate, it refuses with an error: a wrangler.toml, a Worker script (main), run_worker_first

Host / CSS entries

• @excom/vite-plugin-nucleus/host serveSite({ root, port?, shell? }) serves a build as the preview does, on every network interface, and resolves { port, close() }: for browser checks. With shell, the file nucleus-ssr --save-shell wrote, every prerendered page answers with the untouched shell, the cold origin of nucleus-ssr's cold-render check. Also hostHandler, answerOf, hostOf, rulesOf, redirectsOf, headersOf
• @excom/vite-plugin-nucleus/css cssConfig is the Vite css option the plugin sets, for another Vite config; transformCss(css, from) runs the same chain on one stylesheet

Credits

The host emulation holds portions ported from Cloudflare's workers-sdk: see THIRD-PARTY-NOTICES.md.

Full documentation: https://nucleus.excom.dev/packages/vite-plugin-nucleus