VaultGuard

VaultGuard is a Chainlink CRE-orchestrated ERC-4626 tokenized vault that enforces Proof-of-Reserves safeguards and compliance policies when offchain financial conditions change.
A Chainlink CRE workflow fetches EIP-712 signed reserve/NAV attestations from an HTTP API (custodian/fund admin simulator), reads relevant onchain vault state, evaluates reserve health and attestation freshness, and delivers an authenticated report onchain via the Keystone Forwarder → Receiver path.
The onchain VaultGuardPoRFeed stores verified state (anti-replay nonce, timestamps, coverage ratios) and updates the vault’s operating mode:

• NORMAL: deposits/withdrawals allowed
• LIMITED: deposits disabled; withdrawals allowed with caps
• PAUSED: all operations blocked when data is stale / unsafe
  VaultGuard also integrates Chainlink ACE to enforce per-call compliance controls like allowlists and transaction size limits. An optional AI risk sentinel can tighten only (e.g., NORMAL → LIMITED) but cannot relax safeguards or trigger PAUSED.
  Overall, VaultGuard demonstrates how Chainlink CRE collapses an offchain verification pipeline into deterministic onchain enforcement for tokenized vaults.
  Additional Tenderly VTN demo (sponsor track): https://www.loom.com/share/b9f77e8b58814f5295df8f8070a7e9fb

VaultGuard is built as a CLI-first system with three layers:

1. Offchain Attestation Server (Node/TS)
2. Produces deterministic demo scenarios and serves EIP-712 signed reserve attestations (healthy / limited / stale, plus optional AI signals).
3. Chainlink CRE Workflow
4. Uses HTTP Capability to fetch attestations, EVM Capability to read state and broadcast onchain updates, and the Keystone Forwarder/Receiver path for authenticated report delivery.
5. Onchain Contracts (Foundry/Solidity)

• VaultGuard.sol (ERC-4626 vault) consumes PoR state and enforces RiskMode gating
• VaultGuardPoRFeed.sol verifies reports, tracks lastNonce / asOf / freshness, computes effective mode
• VaultGuardExtractor.sol + ACE policies enforce allowlists and min/max limits during vault calls
• KeystoneReceiver.sol secures the CRE → contract report path
  The demo is reproducible via make demo (Sepolia) and make demo-tenderly (Tenderly VTN) with clear runbooks in docs/DEMO_E2E.md and docs/TENDERLY_VTN.md.