W14: Payment Dispute & Reversal Primitive
Avro Digital requests 3,000,000 CC over 5 months across 3 milestones to design, implement, and release an open-source reference implementation of a payment dispute and reversal primitive for Canton.
Label: financial-workflows-composability Champion: need Champion (outreach in progress via the SIG) Status: Draft
Why
Canton has rich token, allocation, transfer-preapproval, and external-signing primitives but no standardized dispute or reversal primitive. Today every regulated consumer-facing or merchant-facing payment application on Canton would have to build its own dispute lifecycle, evidence-handling, time-locked reversal, and adjudication patterns. This is a place ecosystem fragmentation directly hurts adoption — wallets, custodians, and back-office tooling cannot integrate consistently across applications because each one defines its own dispute shape.
Scope
Three workstreams + integration documentation:
- Workstream A — Dispute initiation, state machine, evidence patterns, anti-griefing pattern guide
- Workstream B — Time-locked reversal windows (card-like / ACH-like / RTP-like configurable profiles)
- Workstream C — Adjudication and resolution patterns (bilateral / arbitrated / regulator-mediated / partial / appeal); adjudicator role is parametric per integration with documented per-shape default fills
- Workstream D — Avro Pay reference integration, multi-shape Daml-test fixture harness, integration documentation
Reference integration
Avro Pay (Avro Digital's payment gateway) is the committed reference integration. Appendix D maps the dispute primitive's abstract concepts onto Avro Pay's concrete SettlementReceipt / PaymentAuthorization templates, the operator + admin adjudicator dual-auth, the global-domain synchronizer routing, and the CIP-0056 transfer-preapproval composition for refund flows. Avro Pay engineering work for adoption is on Avro Pay's existing roadmap and is not funded by this grant.
Composition with existing Canton primitives
The proposal extends rather than replaces. Existing Ecosystem Fit table covers CIP-0056 (composes), CIP-0103 (composes), CIP-0104 (composes; perverse-incentive surface acknowledged with anti-griefing pattern guide), Splice / Amulet (consumed as-is), PR #223 (companion governance work), CantonSwap, x402 (PR #78), and the active in-flight token-standard / settlement / yield grants.
Open source
All deliverables Apache 2.0, public Avro Digital repository.
Refs
- HOUSE_STYLE.md codified patterns 9–13 (architectural-integration rules)
- Companion proposal: W15 Atomic Multi-Leg Settlement Primitive (filed in parallel)
- Avro Digital prior work: SV Governance dApp grant (PR #223), CIP-0105 SV-locking proposal, xCC, Avro Pay
