Error instantiating a Kafka client with the Bun runtime

[arcoraven]

Environment Information

• OS: MacOS 15.2, Linux x64
• Bun version: 1.2.3 and 1.0.0
• confluent-kafka-javascript version: 1.2.0 and 1.0.0

Steps to Reproduce Trying to instantiate the KafkaJS client with the Bun runtime throws an error.

index.ts:

import { KafkaJS } from "@confluentinc/kafka-javascript";
new KafkaJS.Kafka({});

Running it with bun run index.ts:

$ bun run index.ts

107 |         return opts[p] || p;
108 |       })
109 |     );
110 |     tries.push(n);
111 |     try {
112 |       b = opts.path ? requireFunc.resolve(n) : requireFunc(n);
                                                     ^
error: The module 'kafka' was compiled against a different Node.js ABI version using NODE_MODULE_VERSION 108. This version of Bun requires NODE_MODULE_VERSION 127. Please try re-compiling or re-installing the module.
      at bindings (/Users/arcoraven/bun-example/node_modules/bindings/bindings.js:112:48)
      at <anonymous> (/Users/arcoraven/bun-example/node_modules/@confluentinc/kafka-javascript/librdkafka.js:10:5)
      at <anonymous> (/Users/arcoraven/bun-example/node_modules/@confluentinc/kafka-javascript/lib/client.js:15:5)
      at <anonymous> (/Users/arcoraven/bun-example/node_modules/@confluentinc/kafka-javascript/lib/kafka-consumer.js:14:5)
      at <anonymous> (/Users/arcoraven/bun-example/node_modules/@confluentinc/kafka-javascript/lib/rdkafka.js:11:5)
      at <anonymous> (/Users/arcoraven/bun-example/node_modules/@confluentinc/kafka-javascript/lib/kafkajs/_producer.js:1:7)
      at <anonymous> (/Users/arcoraven/bun-example/node_modules/@confluentinc/kafka-javascript/lib/kafkajs/_kafka.js:1:19)
      at <anonymous> (/Users/arcoraven/bun-example/node_modules/@confluentinc/kafka-javascript/lib/kafkajs/index.js:5:8)
      at <anonymous> (/Users/arcoraven/bun-example/node_modules/@confluentinc/kafka-javascript/lib/index.js:1:5)

Bun v1.2.3 (macOS arm64)

Does this library depend on Node.js-specific APIs or V8 engine features that aren't yet implemented in Bun's runtime?

confluent-kafka-javascript Configuration Settings N/A

Additional context

package.json:

{
  "name": "bun-example",
  "module": "index.ts",
  "type": "module",
  "private": true,
  "devDependencies": {
    "@types/bun": "latest"
  },
  "peerDependencies": {
    "typescript": "^5"
  },
  "dependencies": {
    "@confluentinc/kafka-javascript": "1.2.0"
  },
  "trustedDependencies": [
    "@confluentinc/kafka-javascript"
  ]
}

tsconfig.json:

{
  "compilerOptions": {
    // Enable latest features
    "lib": ["ESNext", "DOM"],
    "target": "ESNext",
    "module": "ESNext",
    "moduleDetection": "force",
    "jsx": "react-jsx",
    "allowJs": true,

    // Bundler mode
    "moduleResolution": "bundler",
    "allowImportingTsExtensions": true,
    "verbatimModuleSyntax": true,
    "noEmit": true,

    // Best practices
    "strict": true,
    "skipLibCheck": true,
    "noFallthroughCasesInSwitch": true,

    // Some stricter flags (disabled by default)
    "noUnusedLocals": false,
    "noUnusedParameters": false,
    "noPropertyAccessFromIndexSignature": false
  }
}

[patrykwegrzyn]

I get slightly different error bun: symbol lookup error: node_modules/@confluentinc/kafka-javascript/build/Release/confluent-kafka-javascript.node: undefined symbol: _ZN2v816FunctionTemplate12SetClassNameENS_5LocalINS_6StringEEE

I can see similar for node-rdkafka and others

https://github.com/oven-sh/bun/issues/15923 https://github.com/oven-sh/bun/issues/4290

I guess this one is on bun side to resolve?

[milindl]

To get bun support, either they'll have to support all the nan functions we use (What @patrykwegrzyn has linked above), or else, we will need to transition to N-API which is better supported by bun (https://github.com/oven-sh/bun/issues/158).

However, I think both these alternatives will need a fair bit of work testing and making sure everything works properly. So, at the moment, we don't support bun (or any runtime except node itself).

[cowboyd]

I tried using this today with Deno with a similar result. (In this case the node_module_register() symbol was missing.

By supporting N-API it would gain support for both Deno and Bun

[cowboyd]

Here is a draft of the migration https://github.com/confluentinc/confluent-kafka-javascript/pull/281