Technical blueprint: Mac↔Windows clipboard/file/notification sync product

[muaz978]

What this is

A nine-document technical blueprint for a separate product (working codename Bridgeboard): a menu-bar/tray app that syncs clipboard, files, and notifications between a Mac and a Windows PC — instant on LAN, with an encrypted relay fallback across networks. The docs live under docs/clipboard-sync-blueprint/ temporarily until the product gets its own repository; nothing in Audeon's code is touched.

Contents

• README — document map, the three product invariants (zero-config LAN, works across networks, always E2EE), one-paragraph architecture, phasing.
• 01 Architecture — shared Rust core + thin native shells (SwiftUI / WinUI 3) over UniFFI; full core↔shell interface sketch; end-to-end data flow; HLC-based ordering; failure behavior.
• 02 Tech stack — decisions with rationale and rejected alternatives: Rust core, QUIC (quinn) + pinned-cert TLS, protobuf wire format, SQLite/FTS5 history, distribution outside the App Store, NSIS on Windows.
• 03 Protocol & security — Ed25519 device identities, mDNS discovery, SPAKE2 + SAS pairing ceremony, stream layout, wire schema, explicit threat model with in/out-of-scope table.
• 04 Clipboard engine — per-platform capture/injection details (changeCount polling vs WM_CLIPBOARDUPDATE), three-layer loop prevention, fail-closed per-app exclusions, encrypted searchable history store.
• 05 File transfer — chunked, resumable, BLAKE3-verified transfers over QUIC streams; drag-and-drop UX plumbing per platform.
• 06 Cross-network — transport-selection ladder, rendezvous protocol, hole punching, blind relay data plane, cost model. The paid-tier differentiator.
• 07 Notifications — honest feasibility matrix (Android fully possible, iPhone effectively not); Android companion design.
• 08 Roadmap — milestone-by-milestone coding plan M0–M10 with task checklists, exit criteria, and standing engineering rules.
• 09 Testing/CI/distribution — test pyramid incl. headless two-node integration harness and fuzzing, CI matrix, signing/notarization, licensing via merchant-of-record.

🤖 Generated with Claude Code

https://claude.ai/code/session_01MxnZMRfTMFuS5t9oi4t2Ny

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