Cash-and-Carry Position Opener

WHAT IT DOES

Cash-and-Carry Position Opener is a non-custodial tool that executes basis trades between spot and futures markets. It reads futures contract state, spot market pricing, oracle data, funding rates, expiration timestamps, and collateral requirements to structure a carry position. With a single transaction, it calls openCashAndCarry() on the target futures contract, simultaneously opening a spot position and a corresponding futures position to capture the basis spread. The tool supports both physical delivery and cash-settled contracts, and automatically handles the collateral deposit and position sizing based on user-specified parameters.

HOW TO USE

1. Connect your wallet (EVM-compatible).

2. Paste the futures contract address and spot token address you want to trade.

3. Enter position size, leverage (minimum 1x), expiration timestamp, and collateral amount.

4. Review the estimated basis spread and position preview.

5. Click "open cash-and-carry position" and confirm the transaction in your wallet.

The tool fetches current basis spread from on-chain price feeds and oracles before execution, giving you visibility into the current carry opportunity. After the transaction confirms, your position is live on-chain—no centralized custody, no intermediaries.

TECHNICAL MECHANISM: CHUNKED STATE VERIFICATION

Unlike simple transaction builders that assume perfect RPC responses, this tool implements chunked state verification for all on-chain reads. When fetching oracle data, funding rates, or allowance states, it walks backwards in configurable block ranges and halves the chunk size on failure. This prevents the common "eth_getLogs limit exceeded" error that halts most scanners on public RPCs. Additionally, it double-verifies approvals against current allowance() state rather than relying solely on historical Approval events—because an event log proves an approval happened, not that it still stands. Gas estimation uses receipt.effectiveGasPrice for accurate cost accounting post-EIP-1559, and batched operations are sequential with concurrency caps to avoid nonce conflicts.

WHAT IT CANNOT SEE

This tool cannot verify that the price feed or oracle is accurate, reliable, or uncompromised. It cannot detect if the oracle has been manipulated, if the futures contract has been upgraded or modified, or if the trade path is optimal or front-run. It cannot guarantee execution at the optimal price due to slippage, market volatility, or extreme network congestion. It cannot recover funds if execution fails due to contract bugs, insufficient approvals, or paused/frozen contracts. It cannot verify that the collateral token is legitimate. It cannot predict market movements, price gaps, or flash crashes, nor ensure that the basis spread will converge at expiration. It cannot protect against liquidation risk, collateral shortfalls, or guarantee that physical delivery will be processed correctly. It cannot detect if the underlying futures protocol has been compromised, and it cannot prevent you from canceling or modifying trade parameters.

PLEASE NOTE

This tool operates only on EVM-compatible chains (Ethereum, Polygon, Arbitrum, Optimism, etc.). It is non-custodial—you retain full control of your funds at all times. Always verify contract addresses and parameters before executing. The tool is provided as-is; use at your own risk. Past basis performance does not guarantee future results.