Proton is a library for speaking AMQP, including:

• The AMQP Messenger API, a simple but powerful interface to send and receive messages over AMQP.
• The AMQP Protocol Engine, a succinct encapsulation of the full AMQP protocol machinery.

Proton is designed for maximum embeddability:

• minimal dependencies
• minimal assumptions about application threading model

Proton is designed to scale up and down:

• transparently supports both simple peer to peer messaging and complex globally federated topologies

Proton is multi-lingual:

• Proton-C - a C implementation with lanuage bindings in Python, Php, Perl, Ruby, and Java (via JNI).
• Proton-J - a pure Java implementation

Please see http://qpid.apache.org/proton for a more info.