Smart Contracts

The Clout Cards smart contract handles all on-chain asset management.

Contract Overview

Item	Value
Network	Base Sepolia
Contract	CloutCards (Upgradeable Proxy)
Standard	ERC-1967 Proxy Pattern

Core Functions

Deposits

function deposit() external payable

• Accepts ETH and credits the sender's escrow balance
• Emits Deposited(address indexed player, uint256 amount)
• No minimum deposit required

Withdrawals

function withdraw(
    address to,
    uint256 amount,
    uint256 nonce,
    uint256 expiry,
    uint8 v,
    bytes32 r,
    bytes32 s
) external

• Requires server signature (prevents unauthorized withdrawals)
• Signature includes nonce and expiry for security
• Transfers ETH to the specified address

Escrow Balance

Each player has an escrow balance tracked on-chain:

mapping(address => uint256) public escrowBalances;

• Increased by deposits
• Decreased by withdrawals
• Game winnings/losses are handled off-chain, then settled via withdrawals

Events

Event	Parameters	Description
Deposited	player, amount	ETH deposited to escrow
Withdrawn	player, to, amount	ETH withdrawn from escrow

Security Features

Signature Verification

• Withdrawals require EIP-712 typed signatures
• Server signs with TEE private key
• Prevents unauthorized withdrawals

Nonce System

• Each withdrawal has a unique nonce
• Prevents replay attacks
• Tracked per-player

Expiry

• Signatures expire after a set time
• Prevents stale withdrawal requests
• Currently: 5 minutes

Upgradeability

The contract uses the ERC-1967 proxy pattern:

• Proxy Contract: Holds state and delegates calls
• Implementation: Contains logic, can be upgraded
• Admin: Can upgrade implementation (multisig recommended)

Upgrade Risks

Contract upgrades should be carefully reviewed and tested. State corruption is possible if not handled correctly.