jackal-nx is a free, open-source, high performance XMPP server which aims to be known for its stability, simple configuration and low resource consumption. Supports SSL/TLS. Supports Postgres for persistent storage. Clustering-aware (with etcd). Tries to be cross-platform. Requires Postgres as its back end.
Our mission is to promote new technologies, protect privacy and protection of human rights. When you yourself encrypt your messages and using jabber, we can not know what you're talking about.