Not able to execute the tutorial

When I use the Stack file I am able to use `stack build` with it. However I have changed my port to 8081 then. Afterwards I run the `stack exec myproj-exe' but it just stuck in the terminal without any output. What is happening then?

Reproduce the tutorial using the Stack file, changing the port to 8081, then run `stack build` and `stack exec myproj-exe`. Start by checking the tutorial entry point and whether the command is expected to wait without output; done means identifying and documenting the cause or confirming a fix for the stalled execution.

Written by the indexing model from the issue text.