Smart Contracts

PAY.ID consists of 5 main contracts. All are deployed on Lisk Sepolia — no redeployment needed.

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RuleItemERC721

Address: 0xa513E6E4b8f2a923D98304ec87F64353C4D5C853

ERC-721 contract for Rule NFTs. Every rule is represented as an NFT with an expiry tied to the subscription owner.

subscribe()     → activate account, 0.0001 ETH / 30 days
createRule()    → register rule definition (no NFT minted yet)
activateRule()  → mint NFT, ruleExpiry[tokenId] = subscriptionExpiry

function subscribe() external payable
function createRule(bytes32 ruleHash, string calldata uri) external returns (uint256 ruleId)
function activateRule(uint256 ruleId) external returns (uint256 tokenId)
function burnExpired(uint256 tokenId) external

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CombinedRuleStorage

Address: 0x5FbDB2315678afecb367f032d93F642f64180aa3

Registry for combined rule sets. One address = one active rule set.

function registerCombinedRule(bytes32 ruleSetHash, address[] calldata ruleNFTs, uint256[] calldata tokenIds, uint64 version) external
function activeRuleOf(address owner) external view returns (bytes32)
function getRuleByHash(bytes32 ruleSetHash) external view returns (address owner, RuleRef[] memory rules, uint64 version)
function deactivateMyCombinedRule() external

• Max 10 Rule NFTs per combined set
• One address can only have one active rule set

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PayIDVerifier

Address: 0xDc64a140Aa3E981100a9becA4E685f962f0cF6C9

Trust anchor — verifies Decision Proofs and enforces rules. All payments must go through this.

function verifyDecision(Decision calldata d, bytes calldata sig) external view returns (bool)
function requireAllowed(Decision calldata d, bytes calldata sig) external
function setTrustedAuthority(address authority, bool trusted) external onlyOwner

requireAllowed() checks: signature validity → nonce replay → trusted authority → rule ownership → rule expiry.

struct Decision {
  bytes32 version; bytes32 payId;
  address payer; address receiver; address asset; uint256 amount;
  bytes32 contextHash; bytes32 ruleSetHash; address ruleAuthority;
  uint64 issuedAt; uint64 expiresAt;
  bytes32 nonce;
  bool requiresAttestation;
}

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PayWithPayID

Address: 0x610178dA211FEF7D417bC0e6FeD39F05609AD788

Entry point for all payments.

function payERC20(Decision calldata d, bytes calldata sig, bytes32[] calldata attestationUIDs) external
function payETH(Decision calldata d, bytes calldata sig, bytes32[] calldata attestationUIDs) external payable

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Error Reference

Error	Contract	Cause
RULE_LICENSE_EXPIRED	PayIDVerifier	ruleExpiry[tokenId] is past
RULE_AUTHORITY_NOT_TRUSTED	PayIDVerifier	ruleAuthority not whitelisted
RULE_OWNER_MISMATCH	PayIDVerifier	Rule does not belong to receiver
NONCE_ALREADY_USED	PayIDVerifier	Proof already used (replay)
PAYID: INVALID_PROOF	PayIDVerifier	Invalid signature or expired proof
RULE_SLOT_FULL	RuleItemERC721	Max rule slot reached
MAX_10_RULES	CombinedRuleStorage	Combined set > 10 rules
TRANSFER_FAILED	PayWithPayID	ERC20 transferFrom failed