In the case that it is not in the operating system, it is not necessary to run in the operating system. but I do not know what to do,
When it deploys the site it goes all beauty when I go to connect the client does not return anything the client stays in my house and the server in the heroku observes that it is sculpted in port 3000.
The connection line is configured with the address of the application and the port 3000 that he sculpted.
Obs. Another server works beauty both the socket.io and the socket ws. If you want to put client and server to try maybe you can even take advantage of a code.
Try to deploy the server to see if it works.