tox_push_msg_app VS bigbrother-specs

It's not hard for IRC-style chats, but it gets harder if you want to handle:

* Asynchronous messaging: what if the two devices are not online at the same time, or on disjointed networks? Store the message on a server somewhere? Secure Scuttlebutt[1] relies on devices pulling encrypted data that does not belong to them.

* NAT or firewall hole-punching, though it can be remediated by leveraging other nodes. Some implementations use a DHT[2], but you're often relying on other servers of some sort.

* What you call contact discovery is also typically handled through a DHT of some kind. Yggdrasil-like (or hyperboria, cjdns, .onion) overlay networks are usually able to route to a public key, regardless of how it moves around on the network.

* Push notifications. Either you accept the use of an external server (like the Tox client TRIfA, which has an add-on[3])

[1] https://scuttlebutt.nz/docs/introduction/detailed-start/#mor...

[2] https://blog.ipfs.tech/2022-01-20-libp2p-hole-punching/

[3] https://github.com/zoff99/tox_push_msg_app

Related: Are there any standards, APIs, best practices for p2p peer discovery?

I found this https://github.com/status-im/bigbrother-specs/blob/master/da... but it is several years old and doesn't contain much info on peer discovery.