MEV: the hidden tax
Every block, sophisticated bots front-run, back-run, and sandwich trades — extracting value that would otherwise reach normal users.
> What MEV is
Maximal Extractable Value is the profit a block producer (or a bot paying the producer) can capture by reordering, inserting, or censoring transactions within a block. Common tactics: front-running a big swap, sandwiching a DEX trade, and arbitraging price gaps across pools.
> How it affects you
If you swap on a public DEX with high slippage tolerance and no protection, you're a target. The sandwich bot buys just before you, pushes the price up, lets your trade execute at the worse price, then sells — your loss is their profit.
> Protection
Use private RPCs (MEV Blocker, Flashbots Protect) or aggregators that route through private orderflow (CoW Swap, 1inch Fusion). Set tight slippage on volatile pairs. On L2s and Solana, MEV exists but the dynamics differ.