Cajo is a very simple way to have two JVM's communicate across a local area network.
Cajo was written by John Catherino who died in 2016 without designating a future maintainer. Thorbjørn Ravn Andersen used Cajo for internal development in a previous job and mavenized it and added a copy of the java.net resources when it went dark. In 2018 he needed this for a simpler-than-multipart-REST-services feature, so decided to clean the project up and get it on Maven Central.
License of this code is LGPL 3.
Official orbituary: http://www.legacy.com/obituaries/freep/obituary.aspx?pid=179617006
Archived copies of the original project pages: