In-memory message queue with an Amazon SQS-compatible interface. Runs stand-alone or embedded.
Alpakka is a Reactive Enterprise Integration library for Java and Scala, based on Reactive Streams and Akka.
Message queueing system with an actor-based Scala and Amazon SQS-compatible interfaces. Runs stand-alone or embedded.
A lightweight Scala AMQP client
Service Bus for java/scala services with RabbitMQ transport