examples/iroh_gossip.rs proves account → {EndpointId} the P2P way: two endpoints
derive the same gossip TopicId = sha256(account) (its first 4 bytes are today's
room_for_account, so the models line up), join the topic, and learn each other's
public keys by broadcasting presence — zero hardcoded addresses in steady state.
Bootstrap is the one fact gossip can't self-supply: the joiner needs one peer's
EndpointId, and iroh's discovery (n0 DNS here, a tiny rendezvous supernode in
production) maps id→addr. Everything after first contact is peer gossip. A
GossipPresence MeshEvent source would emit Present/Discovered, retiring the SSE
presence bus. iroh-gossip compiles to WASM, so the web client gets the same
discovery unchanged.
iroh-gossip 0.101 added as a dev-dependency (tracks iroh ^1). Verified:
`cargo run --example iroh_gossip` → "✅ gossip discovery: both endpoints found
each other ... with zero hardcoded addresses", clean graceful shutdown.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
