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private transactions

How to send a single transaction to Flashbots#

If you want to send a single transaction to Flashbots without sending it as a bundle, you can use the eth_sendPrivateTransaction method.

This method sends your transaction to the Flashbots builder on every block for a maximum of 25 blocks. No need to listen for the next block and re-send yourself.

Private transactions can be cancelled with the eth_cancelPrivateTransaction method. Once a transaction is included in a block and received by proposers, we cannot "recall" it. However, we can stop including transactions in future blocks.

See RPC endpoint for JSON-RPC definitions of the methods.

These methods are currently implemented in ethers-provider-flashbots-bundle.js and web3-flashbots.py.

const signer = Wallet.createRandom()const provider = new providers.JsonRpcProvider("http://localhost:8545")const flashbotsProvider = await FlashbotsBundleProvider.create(provider, signer)
const transaction = {    from: signer.address,    to: signer.address,    value: "0x42",    gasPrice: BigNumber.from(99).mul(1e9),    gasLimit: BigNumber.from(21000),}
const res = await flashbotsProvider.sendPrivateTransaction({    transaction,    signer,}, {    maxBlockNumber: (await provider.getBlockNumber()) + 5, // only allow tx to be included for the next 5 blocks});
const waitRes = await res.wait();if (waitRes === FlashbotsTransactionResolution.TransactionIncluded) {    console.log("Private transaction successfully included on-chain.")} else if (waitRes === FlashbotsTransactionResolution.TransactionDropped) {    console.log("Private transaction was not included in a block and has been removed from the system.")}