Quotes and signing

A quote is an EIP-712 typed message. The contract hashes exactly this structure, so any field changed after signing fails the signature check.

struct Quote {
  address maker;   // who pays and receives; the signer
  address base;    // NVDA, SPY, TSLA or WETH token
  address quote;   // USDG
  uint256 bid;     // USDG units the maker pays per 1e18 base, when you sell
  uint256 ask;     // USDG units the maker charges per 1e18 base, when you buy
  uint256 size;    // max base units, either side
  uint256 expiry;  // unix seconds
  uint256 nonce;   // single use, cancellable
}

const DOMAIN = {
  name: "Dark Desk",
  version: "1",
  chainId: 4663,
  verifyingContract: "0x0785646d7323F274E20E287A883E60679097082A",
};

The domain's name is "Dark Desk": it is the settlement contract's on-chain name and is part of every signature, so it stays as deployed.

Prices and amounts

Prices are USDG raw units (6 decimals) per 10¹⁸ base raw units, which is the price of one whole token in micro-dollars. NVDA at $212.29 is 212290000. The USDG leg of a fill is amount × price / 1e18, rounded up when you buy and down when you sell, so rounding always favours the maker by less than one micro-dollar.

The stock tokens carry an ERC-8056 multiplier (uiMultiplier), so one raw token can be slightly more than one share after a dividend. Pool prices are already per raw token. House agents convert venue prices through the multiplier before using them.

Nonces

Nonces are bits in a per-maker bitmap: word nonce >> 8, bit nonce & 255. A fill spends the quote's nonce whichever side it takes and whatever amount, so a quote settles at most once. A maker withdraws any set of outstanding quotes in one call:

function cancelNonces(uint256 word, uint256 mask) external;
function isNonceUsed(address maker, uint256 nonce) external view returns (bool);

House agents draw 64-bit random nonces, so two quotes collide with negligible probability.

Contract makers

If maker has code, the contract calls its isValidSignature (EIP-1271) instead of ecrecover, so a safe or a smart account can quote. Plain signatures must be 65 bytes with a low s.

Request for quote

Settlement