Pre-implementation planning document for kez-chat — a Keybase-class chat
and file sharing app built on the KEZ stack.
Architecture (no code yet, just the plan):
- Identity: KEZ ed25519 primary keys; handles look like
@username@kez.lat (placeholder default home server).
- Messaging: NATS broker, dumb relay, clients do E2E with
ChaCha20-Poly1305 over X25519-derived keys. nkeys-auth means the
user's KEZ primary key literally IS their NATS credential.
JetStream handles offline delivery.
- File transfer: Iroh peer-to-peer, content-addressed blobs.
On-demand fetch (no folder sync, no surprise downloads).
Shared-files manifest committed via a new sigchain `set_shared_files`
op; per-entry encryption for private shares.
Server: a single Rust binary `kez-chat-server` that bundles the
handle registry, NATS auth callout, optional sigchain mirror, and
optional Iroh pinning. NATS broker and Iroh node run alongside it.
Includes:
- End-to-end flows (account creation, add contact, send message,
share file, browse files)
- Proposed folder restructure: pull kez-core + kez-channels out into
a top-level `rust-lib/` workspace so downstream projects (sig-server,
chat-server, future) can path-depend cleanly without reaching into
each other's crate trees
- MVP scope and explicit out-of-scope list
- 7 open design questions with my recommended defaults
- Sequenced build plan (refactor first → server scaffold → NATS auth
→ CLI client → Iroh → manifest → deploy → GUI)