MEV
MEV (Maximal Extractable Value) is the profit that can be extracted by reordering, including, or excluding transactions in a block beyond standard block rewards and fees. It is the on-chain equivalent of high-frequency trading edge, plus features unique to public mempools and smart-contract composability.
✦ Key Insight
MEV is paid by ordinary traders, often invisibly, through worse fill prices on swaps and lower returns on LP positions. Understanding MEV — and how to defend against it — is essential for anyone trading on-chain at meaningful size.
✕ Common Misconceptions
Setting wide slippage on large trades, painting a target on yourself.
Using public RPC endpoints when private order flow services exist.
Assuming MEV only affects huge swaps — it scales to whatever size is profitable.
Detailed Explanation
How It Works: Searchers run bots that scan the mempool for profitable patterns: arbitrage across DEXes, liquidations, sandwich attacks against large swaps. They submit bundles to block builders, who include them in the optimal order. Validators receive a share of MEV through proposer-builder separation.
FAQs:
Is all MEV bad? No — arbitrage MEV often improves market efficiency. Sandwich MEV is purely extractive.
How do I avoid being MEVed? Use private RPCs (Flashbots Protect, MEV Blocker), tight slippage, and intent-based execution where possible.
In Practice
Dig Deeper
Arbitrage
Arbitrage is a trading strategy where a trader buys the same crypto asset on one exchange at a lower price and sells it on another exchange at a higher price. The goal is to profit from the temporary price difference between markets.
Slippage
Slippage is the difference between the price a trader expects when submitting an order and the actual price at which the trade executes. Slippage is common in crypto markets and is usually more noticeable during high volatility or when trading low-liquidity tokens.