Overview
The relay never sees your data. Not encrypted-at-rest-but-we-have-the-keys. Actually zero knowledge. The relay is a dumb pipe that routes ciphertext between your devices. No accounts, no key escrow. Keys derive from your passphrase via Argon2id. Pure Rust, no runtime, designed for edge hardware, slow networks, and battery-constrained devices.
Architecture
Highlights
Zero-knowledge relay — the server can't read your data, even if compromised
No accounts — devices pair via passphrase or QR code
Hybrid post-quantum transport — Noise XX with ML-KEM-768 + X25519 (Ring 2) — E2E verified
Multi-relay failover — connect failover, push fan-out, per-relay cursor tracking
DNS-based relay discovery — TXT records on Cloudflare, DNS-over-TLS resolution, no hardcoded NodeIds
750+ tests (604 workspace + 52 JS/pytest + 63 chaos Docker/distributed + 15 Q tool + 10 crypto-probe) — 6/6 relay integration
Relay observability — 14 Prometheus metrics, JSON health endpoint, per-request debug logging
Transport-agnostic core — sync-types and sync-core have zero iroh dependencies
Multi-language bindings — Node.js/Bun (napi-rs) and Python (PyO3)
Large file support with content-addressed hashing (BLAKE3) and chunked transfer