poh-deposit-recoverer

This repository contains a simple Flashbots "searcher" for submitting a transaction from an executor account, but paying for the transaction from a sponsor account. This is accomplished by submitting a Flashbots transaction bundle, with the first "sponsor" transaction paying the "executor" wallet in ETH, followed by a series of executor transactions that spend this newly received ETH on gas fees.

For more information, see the Flashbots Searcher Quick Start

Use case

The use case for this multi-transaction setup is to recover the submission deposit made by a compromised account to the Proof of Humanity registry (see https://app.proofofhumanity.id).

Using this searcher, you can create a bundle of transaction that execute against the compromised account, spending ETH that was received in the same block.

With the activation of EIP-1559, the old method of using gasPrice = 0 is no longer functional. Transactions must pay at least baseFee.

Environment Variables

• ETHEREUM_RPC_URL - Ethereum RPC endpoint. Can not be the same as FLASHBOTS_RPC_URL
• PRIVATE_KEY_EXECUTOR - Private key for the compromised Ethereum EOA that has the submission deposit locked in the Proof of Humanity contract.
• PRIVATE_KEY_SPONSOR - Private key for an account that has ETH that will be used to fund the compromised Ethereum EOA (executor) for the transactions.
• FLASHBOTS_RELAY_SIGNING_KEY - Private key used to sign messages to Flashbots to establish reputation of profitability. This can be a virgin (non-funded) account.

Setting Miner Reward

Inside src/index.ts is :

const PRIORITY_GAS_PRICE = GWEI.mul(31)

This is the priority fee, on top of baseFee, sent to the miner for all transactions in the bundle, including the sponsor-funding transaction. All transactions use the same gasPrice, with no coinbase transfers in any transaction. In the case of a block re-organization, hopefully all transactions will appear in the next block as well, preventing sweeper bots from gaining access to the incoming ETH before it is spent on gas fees.

Usage

Fill the environment variables in src/environ.json

$ npm install
$ npm run burn (in a different terminal)
$ npm run start