“Frontrunning on EVM is the practice of watching blockchain transactions in order to gain an advantage. It occurs when someone watches a transaction being broadcast to the network, and then quickly submits their own transaction before the original is mined, thus allowing them to benefit from the original transaction.” - In other words, MEV bots use your maximum slippage to their benefit, and slurp your money.
How to protect yourself from this?
Use an anti-MEV RPC so your transactions are not visible in the mempool, thus preventing your TX from getting sandwiched. Some generic best practices:
- Minimizing the slippage can help prevent MEV from profiting off your transactions.
- If you swap large amounts, you can use CowSwap - why?
- Try to use DEX aggregators
Use a private MEV RPC
Anti-MEV RPC providers
Here are some alternative, private RPCs you could (should) use.
Flashbots
Simply use the fast one below or configure your custom RPC.
https://rpc.flashbots.net/fast
LlamaNodes
https://eth.llamarpc.com
MEVblocker
From the CowSwap team.
https://rpc.mevblocker.io
https://rpc.mevblocker.io/noreverts
https://rpc.mevblocker.io/fullprivacy
Eden Network
| RPC | Frontrunning Protection | Transaction Speed |
|---|---|---|
| Eden RPC | Guaranteed  |
Fast  |
| Eden Rocket RPC | Best Effort  |
Faster  |
https://api.edennetwork.io/v1/rpc
https://api.edennetwork.io/v1/rocket
Which do I choose?
It really does not matter a lot… read the documentation of the RPC’s as in some cases you need to pick between speed or privacy. Tools to check your ping to several RPC servers.
Trading Bots
Most trading bots like BananaGun, Maestro and Photon have built-in MEV protection.
Why is MEV’ing possible?
This is possible on the Ethereum blockchain because the network is open and all transactions are publicly visible. This practice can be used to manipulate the market by taking advantage of the opportunity to gain profits or prevent losses before other market participants."
I want to know more!
Medium article: Flashbots: Frontrunning the MEV crisis | Flashbots
