- Cl-BUNNY - RabbitMQ Client - CL-BUNNY is a RabbitMQ client
- CL-HRAC - RabbitMQ Management HTTP API in Common Lisp
- cl-stomp - cl-stomp is an implementation of STOMP (Streaming Text Orientated Messaging Protocol)
- cl-xmpp - cl-xmpp is an XMPP client implementation of RFCs 3920 and 3921 which can be thought of as the basis of any Jabber-compliant client
- cl-zmq - cl-zmq is a set of CFFI bindings for ZeroMQ messaging system
- CLAIM - CLAIM is an implementation of AOL's semi-open Instant Messaging protocol, TOC (see PROTOCOL.txt)
- Climc - A Common Lisp Instant Messaging Client
- de.setf.amqp - de setf amqp is a native Common Lisp Advanced Message Queuing Protocol client
- erlangen - erlangen is a distributed, asynchronous message passing system for Clozure Common Lisp
- glacier - Lightweight wrapper for making Mastodon bots
- NactivityPub - ActivityPub & ActivityStreams support library for Common Lisp
- pzmq - ZeroMQ 4.0+ CFFI bindings
- tinmop - TUI/GUI client application for Gemini, Gopher, kamid, and Mastodon/Pleroma
messaging