The README says this:
> Visit your server at http://SERVER:8000
>
> Replace SERVER with your server domain or IP. Replace 8000 with your port if it's not 8000 (the default port).
"localhost" is just shorthand for "this computer's IP address". You have to use the computer's actual IP address to get a link for other people to join. You'll also need to port forward the port you're using, if you have a router.
> Visit your server at http://SERVER:8000
>
> Replace SERVER with your server domain or IP. Replace 8000 with your port if it's not 8000 (the default port).
"localhost" is just shorthand for "this computer's IP address". You have to use the computer's actual IP address to get a link for other people to join. You'll also need to port forward the port you're using, if you have a router.