Run multiple workers with specific environment on both

[zalmanlew]

I have two workers
Worker A and B

Both workers have the default environment at the top-level as well as a dev one.

A includes a binding for B (via RPC)

When running locally, I want to run both at once but using my dev env on both

this is the binding from Worker A wrangler

{
  "binding": "WORKER_B",
  "service": "worker-b-dev"
}

using this command to run both at once

wrangler dev -c ./wrangler.jsonc -c ../worker-b/wrangler.jsonc -e=dev --local --persist-to .wrangler

This fails to find worker-b-dev and only works if I change the service binding to worker-b (dropping the -dev)

I need to keep the -dev because when I deploy my dev environment it's named worker-b-dev

How can I get it working when running locally?

[josefaidt]

I'm running into a similar problem, but I found a workaround! I have my website www and an admin API named admin. I'm using "wrangler": "^4.26.0"

tldr

✅ generate types
❌ dev

"preview": {
  "services": [
    {
      "binding": "ADMIN",
      "service": "admin",
      // this is required so typegen knows what export to use
      "entrypoint": "default"
    }
  ]
}

❌ generate types
✅ dev

"preview": {
  "services": [
    {
      "binding": "ADMIN",
      "service": "admin-preview",
      // this is required so typegen knows what export to use
      "entrypoint": "default"
    }
  ]
}

---

this is my admin service config

{
  "$schema": "node_modules/wrangler/config-schema.json",
  "name": "admin",
  "main": "./handler.ts",
  "compatibility_date": "2025-07-25",
  "compatibility_flags": ["nodejs_compat", "global_fetch_strictly_public"],
  "env": {
    "production": {
      // ... some bindings
    },
    "preview": {
      // ... some bindings
    }
  }
}

and code

// handler.ts
import { WorkerEntrypoint } from "cloudflare:workers"

export default class Admin extends WorkerEntrypoint {
  add(a: number, b: number) {
    return a + b
  }
}

My first take at the config was based on the docs here
https://developers.cloudflare.com/workers/runtime-apis/rpc/#example

{
  "$schema": "node_modules/wrangler/config-schema.json",
  "name": "www",
  "main": "./dist/_worker.js/index.js",
  "compatibility_date": "2025-07-25",
  "compatibility_flags": ["nodejs_compat", "global_fetch_strictly_public"],
  "assets": {
    "binding": "ASSETS",
    "directory": "./dist"
  },
  "env": {
    "production": {
      // ...
    },
    "preview": {
      "services": [
        {
          "binding": "ADMIN",
          "service": "admin"
        }
      ]
    }
  }
}

but generating types yielded

declare namespace Cloudflare {
	interface Env {
		ADMIN: Service;
		ASSETS: Fetcher;
	}
}

which didn't include the add method, and that led me to this issue #8902

following the guidance here I added the entrypoint to get the types

"preview": {
  "services": [
    {
      "binding": "ADMIN",
      "service": "admin",
+     // this is required so typegen knows what export to use
+     "entrypoint": "default"
    }
  ]
}

which generated the proper types

pnpm wrangler types worker-env.d.ts -c wrangler.jsonc -c ../admin/wrangler.jsonc -e preview

declare namespace Cloudflare {
	interface Env {
		ADMIN: Service<import("../admin/handler").default>;
		ASSETS: Fetcher;
	}
}

but if I run both in separate terminals, it will fail to connect

pnpm wrangler dev --env preview --persist-to ../../.wrangler/state

17:25:17 [ERROR] Cannot access `add` as we couldn't find a `wrangler dev` session for service "admin" to proxy to.

I noticed I could add the environment

"preview": {
  "services": [
    {
      "binding": "ADMIN",
      "service": "admin",
      // this is required so typegen knows what export to use
      "entrypoint": "default"
+     "environment": "preview"
    }
  ]
}

while this still generates the proper types, it still fails to connect. however, if you remove the environment and add as a suffix to the service:

"preview": {
  "services": [
    {
      "binding": "ADMIN",
-     "service": "admin",
+     "service": "admin-preview",
      // this is required so typegen knows what export to use
      "entrypoint": "default"
-     "environment": "preview"
    }
  ]
}

it breaks typegen but fixes the connection issue

2 + 2 = 4

declare namespace Cloudflare {
	interface Env {
		ADMIN: Service;
		ASSETS: Fetcher;
	}
}

p.s. and I'm also manually specifying the environment in my astro config

// ...
adapter: cloudflare({
  platformProxy: {
    environment: "preview",
    enabled: true,
    persist: {
      // this path is different than the one you specify with wrangler
      path: fileURLToPath(
        // note the added "/v3"
        new URL("../../.wrangler/state/v3", import.meta.url),
      ),
    },
  },
  imageService: "cloudflare",
}),

[josefaidt]

re-reading the original issue description again, what's interesting is that I cannot specify an array of worker config files to reference in my astro config (sort of like tsconfig references?).

creating a separate worker to test with

{
  "$schema": "node_modules/wrangler/config-schema.json",
  "name": "another-one",
  "main": "./handler.ts",
  "compatibility_date": "2025-07-25",
  "compatibility_flags": ["nodejs_compat", "global_fetch_strictly_public"],
  "env": {
    "production": {
      // ... some bindings
    },
    "preview": {
      // ... some bindings
      "services": [
        {
          "binding": "ADMIN",
          "service": "admin",
          "entrypoint": "default",
          "environment": "preview"
        }
      ]
    }
  }
}

export default {
  async fetch(request, env) {
    return new Response(`${await env.ADMIN.add(2, 2)}`)
  },
} satisfies ExportedHandler<Env>

running the dev command

pnpm wrangler dev -c wrangler.jsonc -c ../admin/wrangler.jsonc --env preview --local --persist-to ../../.wrangler/state

✅ generate types
❌ dev

"preview": {
  "services": [
    {
      "binding": "ADMIN",
      "service": "admin",
      // this is required so typegen knows what export to use
      "entrypoint": "default"
    }
  ]
}

✘ [ERROR] Worker "core:user:another-one-preview"'s binding "ADMIN" refers to service "core:user:admin" with a named entrypoint "default", but "core:user:admin" has no such named entrypoint.

❌ generate types
✅ dev

"preview": {
  "services": [
    {
      "binding": "ADMIN",
      "service": "admin",
	  "environment": "preview"
    }
  ]
}

❌ generate types
❌ dev

"preview": {
  "services": [
    {
      "binding": "ADMIN",
      "service": "admin-preview",
      "entrypoint": "default"
    }
  ]
}

✘ [ERROR] Worker "core:user:another-one-preview"'s binding "ADMIN" refers to a service "core:user:admin-preview", but no such service is defined.