Proposal file:
proposals/2026-06-ChainSafe-cip56-erc20-middleware.md — also viewable on the PR's "Files changed" tab.
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Summary
ChainSafe submission for a MetaMask-compatible middleware over CIP-56 tokens on Canton, comprising an Ethereum JSON-RPC API server, a distributed indexer, an Ethereum↔Canton bridge relayer, a MetaMask Snap for non-custodial Canton signing, and an institutional custody path. The result: any MetaMask user or EVM-native dapp, indexer, or explorer can transact against Canton-native tokens through the JSON-RPC surface they already use on Ethereum, while Canton's privacy-preserving ledger model is preserved.
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Checklist
- [x] Proposal file added under
/proposals/ - [x] Milestones and funding amounts defined
- [x] Acceptance criteria included
- [x] Alignment with Canton priorities described
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Notes for Reviewers
- Champion: Viv Dikawar (Canton Foundation) is sponsoring this proposal. Viv is not listed in
sig-directory.md(which is the SIG-specific roster); the sponsorship is a Foundation-staff arrangement outside the SIG roster. - Label:
wallet-apps— the MetaMask Snap (Phase 2) is the user-facing hook, but the proposal also touches dApp Integration (JSON-RPC facade), Canton APIs (indexer), and Financial Workflows (bridge relayer). Routing to any of those SIGs for review is welcome. - CIP-0112 (Token Standard V2) interaction: the proposal is built against ratified CIP-0056 and includes an explicit V2 migration plan with per-layer reuse estimates and a contingency clause (pull V2 work forward into Phase 2 if ratification happens during Phase 2; otherwise V2 lands in Maintenance Year 1). Timeline for V2 shipping is explicitly tied to ratification rather than a fixed date.
- Institutional custody track is dual-path by design: Track A (custody-partner integration, preferred) with a 4-week structured evaluation gate at the start of Phase 2; Track B (in-house KMS-backed signer, fallback) on the same budget envelope if no partnership reached on commercially or technically acceptable terms. No specific custodian is engaged at submission time.
- Existing codebase: much of Phase 1 work is implemented in
github.com/chainsafe/canton-middlewaretoday; this grant funds completion, hardening, security audit, and long-term sustainment rather than greenfield work. - Long-term sustainment: baseline best-effort upkeep (CVE response, critical bug fixes, CIP tracking) is funded by ChainSafe out of pocket post-Year-2 and continues indefinitely. Apache 2.0, public GitHub, MetaMask Snap registry listing all remain available.
