Trade YES and NO shares through escrowed limit orders.

Every order names the outcome, buy or sell side, price, and share amount. Buy orders escrow collateral. Sell orders escrow the selected outcome token. Price is collateral per share on a 1e18 scale and must be greater than zero and at most one.

// price is collateral per share, scaled by 1e18
const price = parseUnits("0.64", 18);
const amount = parseUnits("100", collateralDecimals);

// Escrows collateral for a buy, or outcome shares for a sell.
const orderId = await market.write.createOrder([
  true,  // YES token
  true,  // buy
  price,
  amount,
]);

await market.write.fillOrder([orderId, amount / 2n]);
await market.write.cancelOrder([orderId]);

• fillOrder supports full and partial fills.
• fillOrders skips stale, invalid, and self-owned entries while filling the remaining valid orders. If batch execution itself fails, the transaction reverts instead of succeeding without a fill.
• Gross quote rounds up to collateral precision. A final fill consumes the order's exact remaining quote so partial fills preserve one-for-one accounting.
• Taker buys pay gross quote plus fee; taker sells receive gross quote minus fee.
• Self-fills revert so makers cannot farm their own rebate.
• Only the maker can cancel; cancellation remains available after market resolution.
• The matching endpoint sorts best price first and returns expected average price and any unmatched amount.

YES and NO each trade at their own execution price. For a normalized binary quote, NO Buy now equals 1 − YES Sell now, while NO Sell now equals 1 − YES Buy now. This preserves the crossed perspective of the book.