Glossary
Backrunning
An MEV strategy that places a transaction immediately after a target transaction to capture the opportunity it creates, without altering the target's own execution.
Backrunning is the mirror image of front-running: instead of jumping ahead of a pending transaction, a searcher tries to land directly behind it. The goal is to profit from a state change the target creates — an arbitrage gap opened by a large swap, a fresh liquidation, or a new pool the target just funded.
Unlike a sandwich attack, pure backrunning does not worsen the target's execution, so it is often considered benign or even useful — it can restore prices across venues. Searchers compete for the slot right after a transaction, usually by bidding through private order flow such as Flashbots bundles or MEV-Share, which lets users share the backrunning revenue their transactions generate.