One of the ways to run server locally and exposing the server externally is using ngrok. In context of kite api, this can be used to expose postback url to internet so that kite server can call it directly (without the need of external servers). Download relevant binaries from website and run it locally. In this way, we can avoid running external server just for postback urls. If you have some query related to ngrok, post it in the thread and I would try to help you troubleshoot it.
I am no way affiliated with ngrok. I saw several discussion related and thought of sharing it.