It's based on <a target="_blank" rel="noopener noreferrer" href="https://activitypub.rocks">ActivityPub</a> to connect with tools <a target="_blank" rel="noopener noreferrer" href="https://peertube.cpy.re/videos/watch/da2b08d4-a242-4170-b32a-4ec8cbdca701">like Mastodon</a> for example.
It's based on <a target="_blank" rel="noopener noreferrer" href="https://en.wikipedia.org/wiki/WebRTC">WebRTC</a>, a free and open-source project for web browsers.
PeerTube is developed by <a target="_blank" rel="noopener noreferrer" href="https://framasoft.org">Framasoft</a>, a French non-profit popular educational organization on digital issues.
It employs a developer, <a target="_blank" rel="noopener noreferrer" href="https://github.com/Chocobozzz">Chocobozzz</a>, who works since 2018 on PeerTube projects:
<a target="_blank" rel="noopener noreferrer" href="https://packages.joinpeertube.org/api/v1/ping">PeerTube plugins index</a> development and maintenance;
Moreover, Chocobozzz works on internal Framasoft's projects (<a target="_blank" rel="noopener noreferrer" href="https://framapad.org">Framapad</a>, <a target="_blank" rel="noopener noreferrer" href="https://framatalk.org">Framatalk</a>, etc.). In other words, the management of PeerTube projects is operated by only one employee, who has other responsabilities in addition to his workload.
Other Framasoft's volunteers and salaried members also contribute to the PeerTube project on various aspects (strategy, communication, development, community animation). Nevertheless, PeerTube is not developed by a startup with a team of 50 people, and a workflow full of hyper-formatted processes.