Domain

Payments

Institutional cash movement: payouts, PvP, DvP cash legs, workflow/memo privacy. - Stakeholder-only visibility with selective disclosure; ISO/SWIFT linkage when needed. - Measure latency/finality/costs on target L2/app-chain; avoid HTLC brittleness.

Case Studies

Patterns

Vendors

Custody Data & Oracles Funds & Assets Identity & Compliance Payments Post-Quantum Threats Trading

Shortest-path Patterns

Building blocks for payments privacy

Private Stablecoin Shielded Payments

Provide stakeholder-only stablecoin transfers on an L2 or app-chain, with viewing-key or zero-knowledge-proof-based disclosure to regulators and auditors, and the ability to compose atomically with asset legs (DvP) or other cash legs (PvP). Hide amounts, counterparties, and memos from non-participants while still enforcing any issuer-level or regulatory policy bound to the stablecoin.

CR: Medium OS: Partial P: Partial S: Medium

Private PvP (cash to cash) Settlement via ERC-7573

Settle two stablecoin legs against each other atomically while keeping amounts and counterparties visible only to the transacting parties and their auditors. Each leg uses a shielded transfer layer for privacy; the ERC-7573 escrow pattern on both chains conditions release on verified finality of the opposite leg, so neither side settles without the other. The construction avoids the public amounts and timing leakage of plain HTLCs and avoids relying on time-locks for safety.

CR: Medium OS: Partial P: Partial S: Medium

Atomic DvP via ERC-7573 (cross-network)

Enable atomic Delivery-versus-Payment across two networks so that either the asset is delivered and payment is completed, or the asset returns to the seller. The pattern targets institutions that need cross-network settlement with predictable failure behavior, auditability, and optional privacy extensions layered on top.

CR: Medium OS: Partial P: None S: Medium

Low-cost L2 + Off-chain Encrypted Audit Log

Run settlement on a low-cost L2, publish only commitments and hashes on chain, and keep the full transaction facts in an append-only encrypted log off chain. Integrity is anchored by periodic Merkle roots submitted on chain. Regulators and auditors receive scoped decryption keys or predicate proofs. Delivery-versus-payment is expressed through an atomic settlement standard.

CR: Medium OS: Partial P: Partial S: Medium

Private ISO 20022 Messaging & Settlement

Coordinate private ERC-20 settlements between banks using ISO 20022 as the instruction layer. The ISO message binds to the on-chain cash leg, while the cash leg itself settles privately via a shielded mechanism (privacy L2, shielded pool, or confidential token) with regulator-only visibility.

CR: Medium OS: Partial P: Full S: Medium

Vendors

Who builds payments privacy tooling

Chainlink ACE

Modular compliance layer built on the Chainlink Runtime Environment (CRE) to define, execute, and enforce identity- and policy-based controls for digital assets across public and private chains. Core onchain components (CCID, CCT Compliance Extension) pair with CRE services (Policy/Identity/Monitoring managers). Offchain policy execution returns signed approvals; onchain enforcement is required. PII/NPI remains offchain. It enables private transactions, with one of the main target use cases being CBDCs management.

Paladin

Open-source (Apache-2.0) privacy layer under the [Linux Foundation Decentralized Trust](https://github.com/LFDT-Paladin/paladin). Paladin provides the common wallet/vault functions that are needed to interact with all forms of privacy preserving smart contracts. It also provides a model for atomic programmability across these privacy preserving smart contracts, harnessing the power of the underlying EVM shared ledger.

Aztec Rollup

Aztec is a privacy focused rollup (or zk-zk-rollup) on Ethereum that enables private transactions and programmable privacy. It is a fully programmable network where applications can access both private and public state.