Advanced
MEV Mitigation — Hands-on lab
Avoid getting exploited at the mempool layer.
Developer Advanced
6/8 — MEV Mitigation — Hands-on lab
ObserveSubmit the same swap via public RPC vs Flashbots Protect; compare slippage and inclusion latency.
InstrumentLog hashes, nonces, and minOut to see how often public mempool submissions get sandwiched.
import { ethers } from "ethers";
const provider = new ethers.JsonRpcProvider("https://rpc.flashbots.net");
const wallet = new ethers.Wallet(PRIVATE_KEY, provider);
const tx = {
to: ROUTER,
data: swapCalldata,
gasLimit: 300000,
maxFeePerGas: ethers.parseUnits("40", "gwei"),
maxPriorityFeePerGas: ethers.parseUnits("1", "gwei")
};
const signed = await wallet.signTransaction(tx);
const res = await provider.sendTransaction(signed);
console.log("Submitted privately:", res.hash);Steps
- Send a small swap:Via public RPC; check mempool explorers for visibility.
- Repeat via Flashbots Protect/private:RPC; confirm it stays hidden until inclusion.
- Simulate a sandwich on:A forked network to see the impact of wide slippage.
- Tighten slippage and deadlines;:Measure failed vs successful executions.
- Log hashes and inclusion:Slots to spot reorg sensitivity.