Unable to import wasm from `wasm-bindgen` in Cloudflare

Environment

maxi@Maxi:~/personal/nitro-nimiq-core-wasm$ node --version
v22.13.1
maxi@Maxi:~/personal/nitro-nimiq-core-wasm$ pnpm list
Legend: production dependency, optional only, dev only

/home/maxi/personal/nitro-nimiq-core-wasm (PRIVATE)

dependencies:
@nimiq/core 2.0.6

devDependencies:
nitropack 2.10.4

Reproduction

• Stackblitz: stackblitz.com/~/github.com/onmax/nitro-nimiq-core-wasm
• Github: onmax/nitro-nimiq-core-wasm

Describe the bug

When loading a WASM module compiled with wasm-bindgen in a Nitro or NuxtHub project on cloudflare_pages, the module does not start correctly.

My nitro config is as follows:

// nitro.config.ts

export default defineNitroConfig({
  srcDir: "server",
  compatibilityDate: "2025-02-12",
  experimental: { wasm: true },
  wasm: { lazy:true, esmImport: true },
  preset: "cloudflare_pages",
  externals: {
    inline: ['@nimiq/core'] // I was having issues with weird relative paths
  }
});

Dynamic wasm import. Using lazy event handler.

This is inspired by this test and this stackblitz. The code can be found in attempt-1.ts

import init, {PublicKey} from '@nimiq/core/web'
export default defineLazyEventHandler(async () => {
  const mod = await import('./nimiq.wasm?module' as string)
  return eventHandler(async () => {
    await init(mod)
    const publicKey = '82d80b86d9bf1906832e9f0ba4fa69018792f59190075c396b0e85aeac444e55'
    const key = PublicKey.fromHex(publicKey);
    return key.toHex()
  })
});

This produces the following error:

WebAssembly.instantiate(): Argument 0 must be a buffer source

  at __wbg_load (./.nitro/dev/index.mjs:2799:44)
  at __wbg_init (./.nitro/dev/index.mjs:3158:40)
  at process.processTicksAndRejections (node:internal/process/task_queues:105:5)
  at async Object.handler (./.nitro/dev/index.mjs:3196:5) 

Static wasm import.

Inspired by this test. The code can be found in attempt-2.ts

import init, { PublicKey } from '@nimiq/core/web'
// @ts-expect-error this is ok
import mod from './nimiq.wasm'

export default defineEventHandler(async () => {
  await init()
  const publicKey = '82d80b86d9bf1906832e9f0ba4fa69018792f59190075c396b0e85aeac444e55'
  const key = PublicKey.fromHex(publicKey)
  return key.toHex()
})

I get an infinite loading screen and this error is displayed:

[nitro] [unhandledRejection] TypeError [ERR_UNKNOWN_FILE_EXTENSION]: Unknown file extension ".wasm" for /home/maxi/personal/nitro-nimiq-core-wasm/.nitro/dev/wasm/nimiq-9e6ed8aecd4a58a7.wasm
    at Object.getFileProtocolModuleFormat [as file:] (node:internal/modules/esm/get_format:219:9)
    at defaultGetFormat (node:internal/modules/esm/get_format:245:36)
    at defaultLoad (node:internal/modules/esm/load:120:22)
    at async ModuleLoader.loadAndTranslate (node:internal/modules/esm/loader:483:32)
    at async ModuleJob._link (node:internal/modules/esm/module_job:115:19) {
  code: 'ERR_UNKNOWN_FILE_EXTENSION'

Maybe related to this issue: https://github.com/harlan-zw/nuxt-seo/issues/160

Using with NuxtHub

The previous reproductions are errors that I have in my dev server. However, in my other reproduction using NuxtHub I was able to run the code in my dev server. The problem was that when I tried to deploy in a Cloudflare Worker I got problems. Please see the issue in https://github.com/nuxt-hub/core/issues/467

Additional context

Other reproductions

• Minimal reproduction of the issue is available using only wrangler. The reproduction repository can be found here and it was successfully deployed at this URL. This reproduction works.
• Minimal reproduction using NuxtHub

Related issues

This issue was first open in https://github.com/nuxt-hub/core/issues/467

Patching @nimiq/core@2.0.6

You need to patch @nimiq/core in order to fix the import for web sub-module to be able to import it. See the patch. This will be fixed in 2.0.7.

Logs

Start with nitro.config.ts and the server/routes/attempt-1.ts and attempt-2.ts reproductions, then compare them with test/fixture/routes/wasm/dynamic-import.ts and static-import.ts. Run the linked StackBlitz or reproduction projects using the cloudflare_pages preset and verify that both dynamic and static wasm imports initialize without the reported buffer-source or unknown-extension errors.