Change the Port?

Hello, Thank you for posting this! I'm looking forward to trying it out. I'm trying to modify the ports used. I noticed them in the Dockerfile and changed them, then ran through the yarn, build, start process. No joy. I'm not well trained in npm/yarn at all. Is there a way to set this or is it completely hard-wired?

Again, thanks! It looks like this is exactly what I've been looking for!