Ecosystem:Message-oriented middleware (MOM)

ejabberd

Provider -- ProcessOne
Website -- http://jabberd2.org/https://www.ejabberd.im/https://www.ejabberd.im/
License -- open source (GPLv2)
Interoperability level -- explicitly supports PostgreSQL (no specific version is specified)
Verified PostgreSQL versions -- didn't actually run the program, but just checked the documentation
Last update (YYYY-MM-DD) -- 2018-3-18
Description -- ejabberd is a distributed, fault-tolerant technology that allows the creation of large-scale instant messaging applications. The server can reliably support thousands of simultaneous users on a single node and has been designed to provide exceptional standards of fault tolerance. As an open source technology, based on industry-standards, ejabberd can be used to build bespoke solutions very cost effectively.
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Provider -- the jabberd team
Website -- http://jabberd2.org/
License -- open source (GPLv2+)
Interoperability level -- explicitly supports PostgreSQL 8.0 or higher
Verified PostgreSQL versions -- didn't actually run the program, but just checked the documentation
Last update (YYYY-MM-DD) -- 2018-3-18
Description -- The Jabberd server is the original open-source server implementation of the Jabber protocol, and it remains the most popular software for deploying Jabber either inside a company or as a public IM service. Jeremie Miller initiated the Jabber Project in 1998 as a free and open alternative to proprietary IM services. The Jabberd server continues to be the core of the Jabber Project, and Jabberd 2 is the successor to the widely used Jabberd 1.4 server. Jabberd 2 is based on a completely new code base with a new architecture, additional features and improved adherence to the Jabber protocol.
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Provider -- Red Hat Inc.
Website -- https://developers.redhat.com/products/amq/overview/
License -- open source (LGPLv2.1)
Interoperability level -- explicitly supports PostgreSQL 9.3.5
Verified PostgreSQL versions -- didn't actually run the program, but just checked the documentation
Last update (YYYY-MM-DD) -- 2018-3-18
Description -- AMQ provides fast, lightweight, and secure messaging for Internet-scale applications. AMQ components use industry-standard message protocols and support a wide range of programming languages and operating environments. AMQ gives you the strong foundation you need to build modern distributed applications.
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Provider -- Prosody dev team
Website -- https://prosody.im/
License -- open source (MIT License)
Interoperability level -- explicitly supports PostgreSQL (no specific version is specified)
Verified PostgreSQL versions -- didn't actually run the program, but just checked the documentation
Last update (YYYY-MM-DD) -- 2017-3-6
Description -- Prosody is a modern XMPP communication server. It aims to be easy to set up and configure, and efficient with system resources. Additionally, for developers it aims to be easy to extend and give a flexible system on which to rapidly develop added functionality, or prototype new protocols.
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