I really want to use Signal but having a centralized server and requiring my phone number turn me off. I'd love to be able to self-build the iOS [0] and desktop [1] apps, and self-host the server [2]. Has anyone tried any of that, are any of them even possible?
On iOS you'd have to constantly redo it via TestFlight or Jailbreak. You could build and install on Android. But "your" binaries won't connect to Signal servers.
> Yes, you can host your own _Signal server and have your own singed apps but it will have to be your own _Signal network, not Moxie/Signal Foundation's Signal.
I don't think that's quite true. You might[0] be discouraged from running your own self-built binaries, but given that Signal Android has reproducible builds[1], I don't think that there's any actual technical barrier. The context of your links is about having (unofficial) third-party packages for Signal, not about somebody building the binary for their own use, and since these are obviously two different things, from a social perspective, I don't think that the Signal foundation would complain much about the latter (given reproducible builds and the fact that you wouldn't be distributing the binaries, they probably wouldn't even know about it).
For Signal-iOS, it seems that you won't get push-notifications if you build by yourself.[2]
[0] I'm not 100 % convinced that "We would not recommend that anyone use an unofficial binary build" was meant to refer to building for yourself, by yourself.
[0]: https://github.com/signalapp/Signal-iOS
[1]: https://github.com/signalapp/Signal-Desktop
[2]: https://github.com/signalapp/Signal-Server