---
id: "queue"
type: "kind"
category: "messaging"
url: "https://localhost:3000/catalogue/kinds/queue"
---

# Queue

Point-to-point message queue. Each message is processed by one consumer.

| | |
|---|---|
| Category | Messaging |
| Properties | 11 |
| Components | 24 |
| Rules | 3 |

## Properties

| property | type | values | required | default |
|---|---|---|---|---|
| `backoff` | enum | `none`, `fixed`, `exponential`, `exponential-jitter` | no | — |
| `deadLetterQueue` | boolean | — | no | false |
| `delivery` | enum | `at-most-once`, `at-least-once`, `exactly-once` | yes | — |
| `instances` | integer | — | no | — |
| `managed` | boolean | — | no | false |
| `maxAttempts` | integer | — | no | — |
| `ordering` | enum | `none`, `per-key`, `global` | no | "none" |
| `persistence` | boolean | — | no | true |
| `replay` | boolean | — | no | false |
| `retentionDays` | integer | — | no | — |
| `role` | enum | `work`, `dlq`, `retry`, `offline-mailbox`, `frontier` | no | "work" |

## Rules for this kind · 3

### Queue without dead-letter queue `queue-missing-dlq` (error)

- Page: https://localhost:3000/catalogue/rules/queue-missing-dlq.md
- Why: A queue that receives asynchronous traffic and has no dead-letter queue either drops poison messages or retries them forever. Neither outcome leaves anything for a human to investigate.
- Applies to: every node of kind queue
- Message: Queue '{{node.id}}' receives async traffic but has no dead-letter queue.

It fires when:

- all of these hold:
  - the node's `deadLetterQueue` is false
  - the node has at least one asynchronous incoming edge

### Retry queue without dead-letter queue `retry-queue-without-dlq` (error)

- Page: https://localhost:3000/catalogue/rules/retry-queue-without-dlq.md
- Why: A retry queue is where poison messages end up. With no dead-letter queue they are retried forever or dropped in silence, and nobody ever looks at the failed payment.
- Applies to: every node of kind queue
- Message: Retry queue '{{node.id}}' has no dead-letter queue. Messages that keep failing must be parked for manual investigation.

It fires when:

- all of these hold:
  - the node's `role` is "retry"
  - the node's `deadLetterQueue` is false

### Retry queue without backoff `retry-without-backoff` (warning)

- Page: https://localhost:3000/catalogue/rules/retry-without-backoff.md
- Why: Retrying a transient failure at full speed turns one slow dependency into a retry storm. A retry queue backs off, preferably exponentially and with jitter.
- Applies to: every node of kind queue
- Message: Retry queue '{{node.id}}' declares no backoff. Retries without backoff amplify the outage they are retrying through.

It fires when:

- all of these hold:
  - the node's `role` is "retry"
  - any of these hold:
    - the node's `backoff` has no value
    - the node's `backoff` is "none"

## Components · 24

### vendor-neutral

- [Generic queue](https://localhost:3000/catalogue/components/queue.md) `queue` — the kind itself

### alibabacloud

- [Simple Message Queue (formerly MNS)](https://localhost:3000/catalogue/components/alibaba-mns.md) `alibaba-mns` — 3 defaults
- [ApsaraMQ for RabbitMQ](https://localhost:3000/catalogue/components/alibaba-rabbitmq.md) `alibaba-rabbitmq` — 3 defaults
- [ApsaraMQ for RocketMQ](https://localhost:3000/catalogue/components/alibaba-rocketmq.md) `alibaba-rocketmq` — 4 defaults

### aws

- [Amazon MQ](https://localhost:3000/catalogue/components/aws-mq.md) `aws-mq` — 5 defaults
- [Amazon SQS](https://localhost:3000/catalogue/components/sqs.md) `sqs` — 5 defaults

### azure

- [Azure Queue Storage](https://localhost:3000/catalogue/components/azure-queue-storage.md) `azure-queue-storage` — 5 defaults
- [Azure Service Bus](https://localhost:3000/catalogue/components/azure-service-bus.md) `azure-service-bus` — 7 defaults

### cloudflare

- [Cloudflare Queues](https://localhost:3000/catalogue/components/cloudflare-queues.md) `cloudflare-queues` — 9 defaults

### default

- [Apache ActiveMQ](https://localhost:3000/catalogue/components/activemq.md) `activemq` — 5 defaults
- [Gearman](https://localhost:3000/catalogue/components/gearman.md) `gearman` — 5 defaults
- [IBM MQ](https://localhost:3000/catalogue/components/ibm-mq.md) `ibm-mq` — 6 defaults
- [Message queue](https://localhost:3000/catalogue/components/message-queue.md) `message-queue` — 2 defaults
- [NSQ](https://localhost:3000/catalogue/components/nsq.md) `nsq` — 6 defaults
- [Apache Qpid Broker-J](https://localhost:3000/catalogue/components/qpid.md) `qpid` — 6 defaults
- [RabbitMQ](https://localhost:3000/catalogue/components/rabbitmq.md) `rabbitmq` — 5 defaults
- [Redis queue](https://localhost:3000/catalogue/components/redis-queue.md) `redis-queue` — 5 defaults
- [Solace PubSub+ Event Broker](https://localhost:3000/catalogue/components/solace.md) `solace` — 6 defaults
- [TIBCO Enterprise Message Service](https://localhost:3000/catalogue/components/tibco-ems.md) `tibco-ems` — 5 defaults

### gcp

- [Google Cloud Tasks](https://localhost:3000/catalogue/components/google-cloud-tasks.md) `google-cloud-tasks` — 8 defaults

### ibm

- [IBM Cloud Messages for RabbitMQ](https://localhost:3000/catalogue/components/ibm-messages-for-rabbitmq.md) `ibm-messages-for-rabbitmq` — 3 defaults
- [IBM MQ on Cloud](https://localhost:3000/catalogue/components/ibm-mq-on-cloud.md) `ibm-mq-on-cloud` — 3 defaults

### oci

- [OCI Queue](https://localhost:3000/catalogue/components/oci-queue.md) `oci-queue` — 5 defaults

### openstack

- [OpenStack Zaqar](https://localhost:3000/catalogue/components/openstack-zaqar.md) `openstack-zaqar` — 4 defaults

## Source (`kind` YAML, verbatim)

```yaml
# yaml-language-server: $schema=../schema/kind.schema.json
# Point-to-point message queue. Each message is consumed by one consumer.
# role distinguishes work queues from dead-letter, retry, offline-mailbox and crawl-frontier uses.
# deadLetterQueue and backoff are deliberately optional so rules can catch their absence.
schemaVersion: "1"
type: "kind"
id: "queue"
category: "messaging"
properties:
  delivery:
    type: "enum"
    values: ["at-most-once", "at-least-once", "exactly-once"]
    required: true
  ordering:
    type: "enum"
    values: ["none", "per-key", "global"]
    default: "none"
  deadLetterQueue:
    type: "boolean"
    default: false
  replay:
    type: "boolean"
    default: false
  retentionDays:
    type: "integer"
  role:
    type: "enum"
    values: ["work", "dlq", "retry", "offline-mailbox", "frontier"]
    default: "work"
  persistence:
    type: "boolean"
    default: true
  backoff:
    type: "enum"
    values: ["none", "fixed", "exponential", "exponential-jitter"]
  maxAttempts:
    type: "integer"
  instances:
    type: "integer"
  managed:
    type: "boolean"
    default: false
```

Human page: https://localhost:3000/catalogue/kinds/queue