multi-worker wrangler dev incorrect remote bindings deduplication behavior

[dario-piotrowicz]

What versions & operating system are you using?

Wrangler@4.23

Please provide a link to a minimal reproduction

No response

Describe the Bug

Let's say that I have 2 workers, worker-a and worker-b with the following wrangler config files:

// wrangler-a.config.jsonc
{
  "name": "worker-a",
  "compatibility_date": "2025-04-03",
  "main": "./index-a.js",
  "services": [
    {
      "binding": "WORKER_B",
      "service": "worker-b",
      "experimental_remote": true
    }
  ],
  "kv_namespaces": [
    { "binding": "MY_KV", "id": "a4f1b5c514214a02b521ad60419b88db", "experimental_remote": true }
  ]
}

// wrangler-b.config.jsonc
{
  "name": "worker-b",
  "compatibility_date": "2025-04-03",
  "main": "./index-b.js",
  "kv_namespaces": [
    { "binding": "MY_KV", "id": "a4f1b5c514214a02b521ad60419b88db" }
  ]
}

If I then run wrangler dev in the following way:

$ npx wrangler dev -c wrangler-a.config.jsonc -c wrangler-b.config.jsonc --x-remote-bindings

and try to interact with the KV binding in both workers I'll see that both bindings are remote, although the second one should actually be local

---

This is caused by some deduplication logic we have in Miniflare that causes only the first binding definition to be used

Please provide any relevant error logs

No response

[dario-piotrowicz]

I think that we should support the case in which two different bindings run in the same wrangler dev instance use the same resource but one in remote mode and the other locally, but arguable that might that be confusing for users

[dario-piotrowicz]

I think that we should support the case in which two different bindings run in the same wrangler dev instance use the same resource but one in remote mode and the other locally, but arguably that might that be confusing for users

We discussed this internally we decided that supporting different modes for the same binding is the correct behavior and it should hopefully not be confusing for users.

We've also agreed that gather from user feedback that instead this is actually confusing people we'll address this by showing a warning when the same binding is used multiple times with different modes (but hopefully things won't come to that since we agree that the warning can be very annoying for developers purposely using this behavior)