It's the successor of the Copperhead OS project. Some details at https://liliputing.com/2019/04/grapheneos-is-an-android-base...
Re:Librem 5 Smartphone Final Specs
by Brakenshire on Monday July 29, 2019 @06:59PM
(#20560368)
Fantastic that it’s open source now.
Do you have anywhere with more information about this/the folks behind it?