Arbitrage on Uniswap V2 Router

Using Gas Price Analysis of the Global TX Mempool and Front-running for sending TX

This is a quick example of getting all pending transactions from a Global TX mempool and filtering those sent to the Uniswap V2 Router. Using the ZMOK Front-running extension to get to the newest block and make an arbitrage.

1. Define what you target

  • Find the smart contract: Uniswap V2 Router (0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D)
  • Find the method signature, the first 4-bytes from the input, directly from the list of pending transactions or from the details of Input Data. (0x38ed1739* filters swapExactTokensForTokens)

The same can be applied to Uniswap V3 Router or any other decentralized exchange.

2. Track queued and pending transactions from around the globe in real-time

To monitor as many transactions as possible in a decentralized blockchain, you’d need to sync with hundreds of nodes around the globe. ZMOK brings you Global TX Mempool, a database where we centralise queued and pending transactions from mempools around the World.

Global TX Mempool is the initial part of the Front-running extension. Purchase it and add a new app with a Mainnet Front-running network. Copy the given FR endpoint (…..)

Use the zmk_txpool_search custom method to search:

curl -X POST

-H ‘Content-type: application/json’

-d ‘{“jsonrpc”: “2.0”, “method”: “zmk_txpool_search”,

“params”:[{“to”: “0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D”, “input”: “0x38ed1739*”}], “id”: 1}’

As a result, you get all queued and pending transactions.

3. Make an arbitrage

Read the highest Gas parameters and set your gas +1gwei. Prepare your transaction to be sent.

Now, you need to get to the same or the newest block. It can be done simply by sending a raw transaction to the front-running endpoint, see the code example:

Example repository

We did an example repository to be customised for your needs:



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