Building a truly decentralized group chat presents significant engineering challenges, particularly around membership management, message ordering, and offline message delivery. The developer behind Kiyeovo, a new desktop P2P messenger, explored several models before settling on a creator-centric approach.

Centralized systems simplify group coordination by using servers to manage rosters, encryption keys, and message order. Decentralized alternatives often punt on dynamic membership (like Briar) or rely on complex protocols like MLS (Tree KEM), which typically require a delivery service. Kiyeovo's design rejects these, opting for a serverless architecture.

Kiyeovo assigns a single creator to each group, identified by an Ed25519 key. This creator manages invitations and removals, solving the problem of conflicting membership updates. Group encryption uses XChaCha20-Poly1305 with rotated sender keys per epoch. New members only receive the key for their joining epoch, limiting historical access. Message ordering and offline delivery are handled via per-sender sequence numbers and an append-only log stored in the DHT.