bug: @kreuzberg/wasm fails to bundle in Next.js — imports node:module, fs/promises, worker_threads

[benjifriedman]

Description

The @kreuzberg/wasm package can't be used in a Next.js app (v16, Turbopack or webpack) because the main entry point (dist/index.js) statically imports Node.js-only modules that don't exist in browser environments.

Errors

With Turbopack (Next.js 16 default):

NftJsonAsset: cannot handle filepath worker_threads

With webpack (next build --webpack):

Module not found: Can't resolve 'fs/promises'
Module not found: Can't resolve 'worker_threads'
Module not found: Can't resolve 'node:module'

Import trace:

node:module
  → @kreuzberg/wasm/dist/pdfium.js
  → @kreuzberg/wasm/dist/index.js

Steps to reproduce

npx create-next-app@latest test-app
cd test-app
npm install @kreuzberg/wasm

Add to any client component:

const { initWasm, extractBytes } = await import("@kreuzberg/wasm");

Run npm run build → build fails.

Relevant files and configuration

- `@kreuzberg/wasm` version: latest
- Next.js 16.1.6
- Node.js 22
- macOS

[benjifriedman]

Suggested fix

Either:

1. Add a "browser" field in package.json that maps Node.js modules to stubs
2. Use dynamic import() for Node.js-specific code paths instead of static imports
3. Provide a separate @kreuzberg/wasm/browser entry point that excludes Node.js dependencies