[MILESTONE] RFP-003 M1 — Design, threat model, LEZ-primitive verification, SDK trait surface

[hackyguru]

Parent Proposal: #112
RFP ID: RFP-003
Team / Grantee: Gateway
Milestone: M1 — Design, threat model, LEZ-primitive verification, SDK trait surface

Deliverables

• Per-leg protocol design write-up covering BTC (Schnorr adaptor + Taproot), XMR (Ed25519 adaptor + cross-curve DLEQ), and ZEC (transparent-pool BIP-199 HTLC; ECDSA adaptor variant noted as follow-on), with cross-chain atomicity argument stated in Aumayr et al. terms (aEUF-CMA, witness-extractability, pre-signature adaptability) for the adaptor legs and a standard HTLC atomicity argument for the ZEC leg.
• LEZ escrow program design including SPEL IDL sketch and the chosen claim/refund path encoding for each pair.
• Threat model covering the adaptor-witness extraction path, the s-malleability path, the timelock-ordering path under each chain's worst-case confirmation latency (including Zcash block-time and reorg characteristics), the spend-key-share recovery path on XMR, and the transparent-pool visibility posture on ZEC.
• Written answer to the two PR RFP-003: unblock atomic swaps, add LEZ primitive status #48 open questions, with reproducer tests committed to the repo: s-malleability of accepted signatures; validity-window enforcement timing (admission vs. validation, inclusive/exclusive semantics).
• Zcash node/wallet decision (zebrad vs zcashd, factoring the deprecation timeline) documented with rationale.
• SDK trait surface published for Logos review (the common SwapProtocol trait + per-pair impl sketches) before implementation commits.
• Embedded KV store choice (sled vs. alternative) decided and justified.
• Maker-daemon integration design for Logos core daemon mode: the remote-control contract the maker mini-app uses to drive the daemon, with a standalone-daemon fallback specified for the period before that Logos capability is delivered (per Logos review feedback).

Payout: $24,500
Duration: 3 weeks (Engineer-weeks: 6 — Igor 2.5 / Elliot 2 / Ivan 1.5)