Hangups is an instant messaging client for Google Hangouts. It includes both a Python library and a reference client with a text-based user interface.

Hangups is implements a reverse-engineered version of Hangouts' proprietary, non-interoperable protocol, which allows it to support features like group messaging that aren’t available to clients that connect over XMPP.

jj is a simple file-system-based Jabber client, inspired by ii IRC client. Interaction with jj is done by writing and reading files from the server directory which jj creates. It is perfect for bots and notifications.

Toxic is a console-based instant messaging client, using c-toxcore and ncurses. It provides audio calls, sound and desktop notifications, and Python scripting support.

OMEMO-wget is a tool to handle cryptographic URLs, generated by OMEMO, during XMPP-based sessions.

GNT is an ncurses toolkit for creating text-mode graphical user interfaces in a fast and easy way. It is based on GLib and ncurses.

ZNC is an IRC network bouncer or BNC. It can detach the client from the actual IRC server, and also from selected channels. Multiple clients from different locations can connect to a single ZNC account simultaneously and therefore appear under the same nickname on IRC.

This package provides Eclipse Mosquitto, a message broker that implements the MQTT protocol versions 5.0, 3.1.1 and 3.1. Mosquitto is lightweight and is suitable for use on all devices from low power single board computers to full servers.

The MQTT protocol provides a lightweight method of carrying out messaging using a publish/subscribe model. This makes it suitable for Internet of Things messaging such as with low power sensors or mobile devices such as phones, embedded computers or microcontrollers.

This module implements XEP-0198: when supported by both the client and server, it can allow clients to resume a disconnected session, and prevent message loss.

This module implements XEP-0357: Push Notifications.

Some platforms, notably Apple’s iOS and many versions of Android, impose limits that prevent applications from running or accessing the network in the background. This makes it difficult or impossible for an XMPP application to remain reliably connected to a server to receive messages.

In order for messaging and other apps to receive notifications, the OS vendors run proprietary servers that their OS maintains a permanent connection to in the background. Then they provide APIs to application developers that allow sending notifications to specific devices via those servers.

When you connect to your server with a client that requires push notifications, it will use this module to set up a “push registration”. When you receive a message but your device is not connected to the server, this module will generate a notification and send it to the push gateway operated by your application’s developers). Their gateway will then connect to your device’s OS vendor and ask them to forward the notification to your device. When your device receives the notification, it will display it or wake up the app so it can connect to XMPP and receive any pending messages.

Relays messages between different channels from various messaging networks and protocols. So far it supports mattermost, IRC, gitter, xmpp, slack, discord, telegram, rocketchat, twitch, ssh-chat, zulip, whatsapp, keybase, matrix, microsoft teams, nextcloud, mumble, vk and more with REST API. Mattermost is not required.

libpsyc is a PSYC library in C which implements core aspects of PSYC, useful for all kinds of clients and servers including psyced.

libqmatrixclient is a Qt library to write clients for the Matrix instant messaging protocol. Quaternion is the reference client implementation. Quaternion and libqmatrixclient together form the QMatrixClient project.

Plugin for libpurple to allow sending SMS using ModemManager.

Profanity is a console based XMPP client written in C using ncurses and libmesode, inspired by Irssi.

Mcabber is a small XMPP (Jabber) console client, which includes features such as SASL and TLS support, Multi-User Chat (MUC) support, logging, command-completion, OpenPGP encryption, Off-the-Record Messaging (OTR) support, and more.

LibGadu is library for handling Gadu-Gadu instant messenger protocol. The library is written in C and aims to be operating system and environment independent.

This package shows CAPTCHA without running proprietary code.

ngIRCd is a lightweight Internet Relay Chat (IRC) server for small or private networks. It is easy to configure, can cope with dynamic IP addresses, and supports IPv6, SSL-protected connections, as well as PAM for authentication.

HexChat lets you connect to multiple IRC networks at once. The main window shows the list of currently connected networks and their channels, the current conversation and the list of users. It uses colors to differentiate between users and to highlight messages. It checks spelling using available dictionaries. HexChat can be extended with multiple addons.

This package contains Zulip's official terminal client.

Movim-Desktop is a desktop application, relying on Qt, for the Movim social and chat platform.

MQTT and MQTT-SN are lightweight publish/subscribe messaging transports for TCP/IP and connection-less protocols (such as UDP). The Eclipse Paho project provides client side implementations of MQTT and MQTT-SN in a variety of programming languages. This package is for the Python implementation of an MQTT version client class.

OTR allows you to have private conversations over instant messaging by providing: (1) Encryption: No one else can read your instant messages. (2) Authentication: You are assured the correspondent is who you think it is. (3) Deniability: The messages you send do not have digital signatures that are checkable by a third party. Anyone can forge messages after a conversation to make them look like they came from you. However, during a conversation, your correspondent is assured the messages he sees are authentic and unmodified. (4) Perfect forward secrecy: If you lose control of your private keys, no previous conversation is compromised.

libsignal-protocol-c is an implementation of a ratcheting forward secrecy protocol that works in synchronous and asynchronous messaging environments. It can be used with messaging software to provide end-to-end encryption.