Hello I wrote a small app to reproduce the problem , I intentionally use only 1 thenable (and one catch) for each promise .

The program starts correctly but freezes because it is waiting for a promise to resolve or reject comming from "findOne" the small program is on github (https://github.com/jacobbogers/jkf-url-shortener), (express, node, mongo)
To run you need to set the following environemnts
PORT, (port number to listen to for json callbacks)
URI_MONGO = url to your mongo db
BASE_URI = your url (or http://localhost:3000 or something if you run locally)

Try creating follow the instructions on the main page , if you enter new URL shortneres (using findOne 2x) it will hange
Is this a known problem?