A friend and colleague of mine developed a simple distributed testing framework in JavaScript - https://github.com/PsychoLlama/panic-server (It works in conjunction with Mocha, Jasmine, and possibly other test frameworks - https://github.com/PsychoLlama/panic-demo)

(We work on an open source distributed data sync engine and needed a way to test distributed aspects of that engine - https://github.com/amark/gun/)