RabbitMQ

Use Nimbus with RabbitMQ or LavinMQ for reliable, broker-backed messaging

The Nimbus RabbitMQ transport connects to any AMQP 0.9.1 compatible broker using the RabbitMQ.Client v7 async API. It is tested against both RabbitMQ and LavinMQ, and works with any broker that speaks AMQP 0.9.1.

If you want a widely-adopted, battle-tested message broker with a rich ecosystem, or a lightweight high-performance drop-in alternative, this transport has you covered.

Installation

dotnet add package Nimbus.Transports.RabbitMQ

Quick Start

Run RabbitMQ

RabbitMQ requires the rabbitmq_delayed_message_exchange community plugin for scheduled message delivery. The easiest way to get this is to extend the official image:

FROM rabbitmq:4-management
RUN rabbitmq-plugins enable rabbitmq_delayed_message_exchange

docker build -t rabbitmq-delayed .
docker run -d \
  --name rabbitmq \
  -p 5672:5672 \
  -p 15672:15672 \
  -e RABBITMQ_DEFAULT_USER=admin \
  -e RABBITMQ_DEFAULT_PASS=admin \
  rabbitmq-delayed

The RabbitMQ management UI is available at http://localhost:15672.

Configure Nimbus

using Nimbus;
using Nimbus.Configuration;
using Nimbus.Transports.RabbitMQ;

var bus = new BusBuilder()
    .Configure()
    .WithNames("OrderService", Environment.MachineName)
    .WithTransport(new RabbitMqTransportConfiguration()
        .WithHost("localhost")
        .WithCredentials("admin", "admin"))
    .WithTypesFrom(typeProvider)
    .WithAutofacDefaults(container)
    .Build();

await bus.Start();

LavinMQ — Lightweight Alternative

LavinMQ is a high-performance, low-resource AMQP 0.9.1 broker written in Crystal. It is fully compatible with the RabbitMQ client protocol and supports delayed messages natively — no plugin required.

LavinMQ is a great fit when you want:

• A lightweight broker with a tiny memory and CPU footprint
• Low-latency messaging with RabbitMQ compatibility
• Simple single-binary deployment
• Native delayed message support without plugins

Run LavinMQ

docker run -d \
  --name lavinmq \
  -p 5672:5672 \
  -p 15672:15672 \
  cloudamqp/lavinmq

The LavinMQ management UI is available at http://localhost:15672.

Configure Nimbus for LavinMQ

LavinMQ uses the same RabbitMqTransportConfiguration as RabbitMQ — just point at your LavinMQ host:

var bus = new BusBuilder()
    .Configure()
    .WithNames("OrderService", Environment.MachineName)
    .WithTransport(new RabbitMqTransportConfiguration()
        .WithHost("localhost")
        .WithCredentials("guest", "guest"))
    .WithTypesFrom(typeProvider)
    .WithAutofacDefaults(container)
    .Build();

await bus.Start();

Configuration Reference

new RabbitMqTransportConfiguration()
    .WithHost("rabbitmq.internal")       // default: "localhost"
    .WithPort(5672)                      // default: 5672
    .WithCredentials("user", "secret")  // default: "guest"/"guest"
    .WithVirtualHost("/my-vhost")        // default: "/"
    .WithManagementPort(15672)           // optional, for management API access

Scheduled Delivery

Both RabbitMQ and LavinMQ support scheduled message delivery via Nimbus:

// Deliver after a delay
await bus.SendAfter(new MyCommand(), TimeSpan.FromMinutes(5));

// Deliver at a specific time
await bus.SendAt(new MyCommand(), DateTimeOffset.UtcNow.AddHours(1));

RabbitMQ uses the rabbitmq_delayed_message_exchange plugin. A single nimbus.delayed exchange is declared at startup; Nimbus routes deferred messages through it automatically using the x-delay header.

LavinMQ supports delayed messages natively using the same x-delay header — no plugin or extra configuration needed.

Topology

Nimbus maps its messaging patterns to RabbitMQ concepts as follows:

Limitations

• Large message support is not available.

Compatibility

• ✅ RabbitMQ 3.x / 4.x (requires rabbitmq_delayed_message_exchange plugin for scheduled delivery)
• ✅ LavinMQ 1.x+ (native delayed delivery, no plugin required)
• ✅ .NET 9.0+