Problem with --experimental-loader with @opentelemetry/instrumentation/hook.mjs in Node.js 24+

[monwolf]

Summary

When using @opentelemetry/instrumentation/hook.mjs with the --experimental-loader flag in Node.js 24+, the application hangs in what appears to be an infinite loop, consuming increasingly more memory over time until the process crashes.

OpenTelemetry Setup Code

import { Producer } from "@platformatic/kafka"
const logger = {
    info: console.log,
    error: console.error,
};

const start = async () => {
    logger.info("App started on port: " + 3000);
};

start();

export {Producer};

package.json

{
  "name": "test-otel",
  "version": "1.0.0",
  "description": "",
  "license": "ISC",
  "author": "",
  "type": "module",
  "main": "dist/index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "tsc:b": "tsc --build"
  },
  "dependencies": {
    "@opentelemetry/api": "^1.9.0",
    "@opentelemetry/auto-instrumentations-node": "^0.67.2",
    "@opentelemetry/host-metrics": "^0.37.0",
    "@opentelemetry/sdk-node": "^0.208.0",
    "@platformatic/kafka": "1.17.1"
  },
  "devDependencies": {
    "typescript": "^5.9.3"
  }
}

tsconfig.json

{
  "compilerOptions": {
    "baseUrl": "./",
    "module": "nodenext",
    "moduleResolution": "nodenext",
    "outDir": "./dist",
    "rootDir": "./src",
    "target": "esnext",
    "strict": true,
    "allowSyntheticDefaultImports": true
  },
  "include": ["src/**/*"],
  "exclude": ["test"]
}

run

    npm run tsc:b
    $env:NODE_OPTIONS = "--experimental-loader=@opentelemetry/instrumentation/hook.mjs"
    node --trace-warnings ./dist/index.js

If I remove the dependency, the application starts fine.

[monwolf]

I have also created the issue in the OTel Issue Tracker.
open-telemetry/opentelemetry-js#6203

[lexomis]

confirming behavior. unfortunately means this library is totally unusable for us.

• on Node 22.20
• @platformatic/kafka 1.22.0
• otel auto instrumentation libs 0.66.0 -> 0.67.2
• meaningfully the same tsconfig

we don't use the experimental loader, just a stock instrumentation.mjs.

tried with only implementing producer, only implementing consumer, and not implementing either but still having lib in packages. all had same behavior reported by op.