A 19-year-old[0] built a video call app[1] with WebRTC and open-sourced[2] it.

Here's a podcast interview[3] about how he did it.

[0]: https://github.com/ianramzy

[1]: https://zipcall.io

[2]: https://github.com/ianramzy/decentralized-video-chat

[3]: https://syntax.fm/show/256/webrtc-and-peer-to-peer-video-cal...