Fixing the tsconfigPaths Error in Astro + Tailwind 4

If you are building an Astro site with Tailwind 4 and your build fails with this error:

[@tailwindcss/vite:generate:build] Missing field `tsconfigPaths` on BindingViteResolvePluginConfig.resolveOptions

You are not alone. This is a compatibility break between Vite 8 (which ships Rolldown) and the @tailwindcss/vite plugin. Here is what is happening and how to fix it.

The Root Cause

Vite 8 bundles Rolldown as its default bundler. Rolldown is a Rust rewrite of Rollup and is significantly faster, but its plugin API is not yet fully compatible with the existing Vite plugin ecosystem. The @tailwindcss/vite plugin relies on a field called tsconfigPaths that Rolldown does not expose. When Astro tries to generate your CSS, the plugin crashes.

The fix is to pin Vite to version 7, which uses the classic Rollup-based bundler and works correctly with Tailwind 4.

The Fix

1. Pin Vite 7 in package.json

Add an overrides field to package.json:

{
  "overrides": {
    "vite": "^7.3.6"
  }
}

Do not add Vite to dependencies or devDependencies at the same time. npm will reject the install with an EOVERRIDE error.

2. Use Node 22.19 or newer

Modern Astro versions require Node 22.12 or newer, and some transitive dependencies require 22.19. Set .nvmrc:

22.19.0

3. Match integration versions to your Astro core

This one is easy to miss. If you are on Astro 5, use @astrojs/sitemap@3.2.1 and @astrojs/rss@4.0.7. Newer versions of those integrations migrate to zod 4, which conflicts with Astro 5 (zod 3) and breaks the build with z.function(...).optional is not a function.

If you are on Astro 6, use the latest versions of those packages.

4. Generate the lockfile the way your build environment does

If your CI uses npm ci, generate the lockfile with plain npm install — not --legacy-peer-deps. Otherwise the lockfile may contain peer-dependency resolutions that npm ci rejects.

rm -rf node_modules package-lock.json .astro
npm install
npm run build

Verifying the Fix

After the build completes, check that the output directory contains your pages:

ls dist/blog/

If your posts are rendering, the build succeeded.

Why This Matters

This class of error is going to become more common as more tools migrate to Rolldown. Pinning Vite 7 is a temporary workaround. The long-term fix will come from the Tailwind team updating their plugin to support Rolldown.

Until then, the combination above is stable and reproducible.