Easiest way for P2P connection WTIHOUT port forwading on a Raspberry Pi?

I've managed to develop an application to easily run Minecraft Servers on a Raspberry Pi. So now, what I'm wondering, is there any way to allow people to connect to the server? I don't want to use port forwarding, because if I embedded the code into my program, I wouldn't want people to have to set up port forwarding on their router. I know it's possible, because games such as Garry's Mod have done it. I have access to hosting a website via GitHub Pages, so could I make a redirect using that to a LAN IP? Any help is appreciated, thanks.