Measure the gap.
Cut it clean.

Read every verified pool at a single block.

Kerf asks the canonical Uniswap V2 and V3 factories for each pool holding an issuer-verified stock token, pulls all of their state in one multicall pinned to one block, and sends every pool a real test quote before it may carry a route.

• An asset is its contract address. A ticker alone proves nothing.
• A pool that cannot fill the test quote is dropped — and listed with the reason.
• Uniswap v4 pools are shown as unsupported instead of priced with the wrong maths.

Quote the loop, then dry-run the exact call.

A candidate starts and ends in the same settlement asset. Each hop is priced by the on-chain quoter at a size scaled to the shallowest pool, every cost gets its own line, and the executor call you would sign is replayed in an eth_call from your own address.

• Pool fees already live inside the quote; they are never taken off twice.
• Gas is converted only with a credible same-block rate — otherwise the net is flagged incomplete.
• Touch the route, size, minimum, deadline or wallet and the rehearsal is void.

Borrow, swap, repay — one transaction or nothing.

The executor flash-swaps from the first pool, runs the remaining hops, repays that pool and enforces your minimum profit, all inside one transaction. If any piece fails, none of it happened.

• Callbacks are accepted only from the one pool expected next.
• Your profit is the contract’s measured balance increase, paid to whoever signed.
• A clean rehearsal is not a promise; a reverted transaction still burns gas.

Reading executor status…

Read the outcome from the receipt, not from hope.

History is built from the executor’s CycleExecuted events and their receipts: what was actually paid out, the protocol fee, the gas you really spent, and whether the block is only on L2 or already final on Ethereum.

• Only a receipt with status success counts. A revert emits no event and shows as a failed transaction.
• Finality comes from the node’s safe and finalized tags — never assumed.
• Net after gas appears only when proceeds and gas are in the same asset.