“sockjs_test_server_nwjs” is just a simple SockJS server running on Node.js but using NW.js (formerly node-webkit) to provide a simple visual interface for testing purposes. It was made on 29th July 2016 (approximately).
The default listening port is set to 9999 but can be modified easily.
It comes with a self-extracting single-file binary for Windows 32-bit (using 7zip‘s SFX) that runs on Windows XP with SP2 (Service Pack 2) minimum and also on newer Windows versions as Windows 10 (generated with Web2Executable) but also includes the source code so it can be ported to other platforms supported by NW.js easily.
It can be found on GitHub: https://github.com/jalbam/sockjs_test_server_nwjs