Turbopack Error Module not found: Can't resolve '../lightningcss.' <dynamic> '.node'

[lancejpollard]

Summary

Been getting this for months now, I am on Next 15.3.1 as of today, and still same issue. I don't know anything about lightningcss, I haven't ever dealt with such a library. My project is pretty basic, not sure where this is coming from. Any help on how to get turbopack working (getting past this issue) will be great.

next build --turbopack

   ▲ Next.js 15.3.1 (Turbopack)
   - Environments: .env

   Creating an optimized production build ...
 ⚠ Webpack is configured while Turbopack is not, which may cause problems.
 ⚠ See instructions if you need to configure Turbopack:
  https://nextjs.org/docs/app/api-reference/next-config-js/turbo

(node:31519) Warning: To load an ES module, set "type": "module" in the package.json or use the .mjs extension.
(Use `node --trace-warnings ...` to show where the warning was created)
 ⚠ Support for Turbopack builds is experimental. We don't recommend deploying mission-critical applications to production.

- Turbopack currently always builds production sourcemaps for the browser. This will include project sourcecode if deployed to production.
- It is expected that your bundle size might be different from `next build` with webpack. This will be improved as we work towards stability.
- This build is without disk caching; subsequent builds will become faster when disk caching becomes available.
- When comparing output to webpack builds, make sure to first clear the Next.js cache by deleting the `.next` directory.

Provide feedback for Turbopack builds at https://github.com/vercel/next.js/discussions/77721

> Build error occurred
Error: Turbopack build failed with 2 errors:
./node_modules/.pnpm/[email protected]/node_modules/lightningcss/node/index.js:22:22
Module not found: Can't resolve '../lightningcss.' <dynamic> '.node'
  20 |     module.exports = require(`lightningcss-${parts.join('-')}`);
  21 |   } catch (err) {
> 22 |     module.exports = require(`../lightningcss.${parts.join('-')}.node`);
     |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  23 |   }
  24 | }
  25 |

https://nextjs.org/docs/messages/module-not-found

./node_modules/.pnpm/[email protected]/node_modules/lightningcss/node/index.js:17:20
Module not found: Can't resolve '../pkg'
  15 |
  16 | if (process.env.CSS_TRANSFORMER_WASM) {
> 17 |   module.exports = require(`../pkg`);
     |                    ^^^^^^^^^^^^^^^^^
  18 | } else {
  19 |   try {
  20 |     module.exports = require(`lightningcss-${parts.join('-')}`);

https://nextjs.org/docs/messages/module-not-found

    at <unknown> (https://nextjs.org/docs/messages/module-not-found)
    at <unknown> (https://nextjs.org/docs/messages/module-not-found)
 ELIFECYCLE  Command failed with exit code 1.

Additional information

Operating System:
  Platform: darwin
  Arch: arm64
  Version: Darwin Kernel Version 24.3.0: Thu Jan  2 20:24:24 PST 2025; root:xnu-11215.81.4~3/RELEASE_ARM64_T6030
  Available memory (MB): 36864
  Available CPU cores: 12
Binaries:
  Node: 20.10.0
  npm: 10.4.0
  Yarn: 1.22.19
  pnpm: 10.8.1
Relevant Packages:
  next: 15.3.1 // Latest available version is detected (15.3.1).
  eslint-config-next: N/A
  react: 19.1.0
  react-dom: 19.1.0
  typescript: 5.8.3
Next.js Config:
  output: N/A

Example

No response

[hussein-raji-mappa]

I was on this issue for about a day. It only started when i upgraded to tailwindcss v4(.1). The issues was my postcss.config.mjs file. I had this:

import tailwindcss from "@tailwindcss/postcss";

/** @type {import('postcss-load-config').Config} */
const config = {
	plugins: {
		tailwindcss: tailwindcss(), // 👈 call the plugin function
	},
};

export default config;

which was incorrect, instead of this:

/** @type {import('tailwindcss').Config} */
export default {
  plugins: {
    '@tailwindcss/postcss': {},
  },
}

as found in the docs. That fixed this bug for me.
After this i just followed the tailwind v3 to v4 upgrade guide and everything worked as expected. Hope this helps you

[Prachiijainn]

thankyou so much

[vishalbac10]

Thank you

[RileyKarlDesign]

Thank you - this saved me today