Queues

Produce messages with env.<binding>.send. Consume with a separate script — not the same module as fetch. celld enforces one consumer Worker per queue; cellp branches queue data on child preview versions and exposes peek/pause/redrive operator APIs.

On cellp, producer and consumer are usually two deploy artifacts—often two versions in the same project—because multi-[[services]] in one wrangler bundle is not supported.

Bindings overview · Binding guides · Platform data

1. Declare a producer

"queues": {
  "producers": [{ "binding": "FULFILLMENT", "queue": "fulfillment" }]
}

queue is the resource name (keep it on child wranglers — names must match the parent or Start fails). binding is env.FULFILLMENT. Configure bindings.

Producer-only example: dev/examples/queue.

2. Send from the HTTP Worker

export default {
  async fetch(request, env) {
    if (request.method === 'POST' && new URL(request.url).pathname === '/api/orders') {
      const order = await createOrder(env.DB, await request.json())
      await env.FULFILLMENT.send({
        type: 'order.placed',
        order_id: order.id,
        at: Date.now(),
      })
      return Response.json(order, { status: 201 })
    }
    return new Response('ok')
  },
}

3. Declare a consumer (separate deploy)

Deploy a second Worker artifact with only queue() — no fetch():

"queues": {
  "consumers": [{ "queue": "fulfillment", "max_batch_size": 10 }]
}

export default {
  async queue(batch, env) {
    for (const msg of batch.messages) {
      await handle(msg.body, env)
      msg.ack()
    }
  },
}

Producer vs consumer

celld allows one consumer script per queue, and that script cannot export fetch(). HTTP and consumption must be two Workers (or HTTP-only with peek/redrive from the operator API).

4. What you see after deploy

• Dashboard → Storage → Queues: peek, pause, resume, redrive, purge
• Child versions branch the queue from the parent
• Root starts empty

Handlers

Operator API

Prefix: /v1/projects/{project}/versions/{version}/

GET  …/queues
GET  …/queues/{name}
GET  …/queues/{name}/peek?limit=
POST …/queues/{name}/pause
POST …/queues/{name}/resume
POST …/queues/{name}/redrive?limit=
POST …/queues/{name}/purge

celld vs Cloudflare

• Messages are retained four days (not configurable).
• Pull consumers and the Cloudflare Queues HTTP API are not available.
• One writer per queue; one consumer script per queue.
• Confirm batching, retries, and dead-letter behavior in celld compat before production billing pipelines depend on queues.