There is also a special mode for the server, which relaunches the server as soon as any of the .js files has changed.
To launch the server in this mode, do not use:
$ node run_server.js
but use:
$ bash run_dev_server.bash
instead.
This will restart the server as soon as anything changed. Remember, that this will not restart the server in case of a crash, to help you noticing whenever a crash occurs.