zk-SPV for Private Cross-Chain DvP

Delivery-versus-Payment (DvP) is fundamental to institutional settlement: asset and cash legs must settle atomically to eliminate principal risk. Current approaches either sacrifice privacy (public atomic swaps) or atomicity (private but conditional). Cross-chain DvP with hidden amounts and true atomicity remains unsolved.

RFP: zk-SPV for Private Cross-Chain DvP

Why It Matters

  • DvP is non-negotiable for institutional settlement (principal risk = regulatory concern)
  • Cross-chain is reality: institutions operate across multiple networks
  • Privacy + atomicity is the "holy grail" for institutional adoption
  • Informs ERC-7573 (draft) extensions and future settlement patterns

Scope

In-Scope

Phase A: Design & Specification

  • Design space analysis for private cross-chain DvP:
    • zk-SPV (succinct cross-chain verification)
    • ZK-HTLC variants
    • Hybrid TEE + ZK settlement
    • Commit-and-prove with fallback
  • Impossibility boundaries (what can't be achieved?)
  • Threat model for each approach
  • Protocol specification for most promising candidate

Phase B: Reference Implementation (optional)

  • Prototype implementation
  • Integration with ERC-7573 (draft) DvP standard
  • Cross-chain proof-of-concept (e.g., Ethereum ↔ L2)

Out-of-Scope

  • Production deployment
  • Multi-leg settlement (3+ assets) — future work
  • Specific L2 integrations beyond PoC

Deliverables

Phase A:

  • Design space document with trade-off matrix
  • Threat model per approach
  • Protocol specification (cryptographic details)
  • Impossibility analysis (what requires trust assumptions?)

Phase B (if funded):

  • Reference implementation (Solidity + off-chain components)
  • Integration guide for ERC-7573 (draft)
  • Cross-chain PoC demo

Dependencies

Requires:

  • Cryptographic research expertise (proof systems, light clients)
  • Understanding of cross-chain finality models

Enables:

  • Private institutional settlement infrastructure
  • Extensions to ERC-7573 (draft)
  • Foundation for multi-leg settlement

See Also