Crypto
A Fresh Wave of MEV Losses Renews Scrutiny of On-Chain Front-Running
Traders on a popular decentralized exchange reported worse-than-expected execution prices this week, reviving a familiar complaint about who really sees a trade before it happens.
A cluster of complaints from traders on a widely used decentralized exchange this week pointed to unusually poor execution prices on otherwise ordinary trades — the kind of pattern that typically gets traced back to MEV (maximal extractable value) activity, the structural, bot-driven version of front-running covered in this week's guide on the topic.
The complaints follow a familiar shape: a trade that should have executed close to the displayed price instead filled meaningfully worse, consistent with another party seeing the pending transaction in the public mempool and inserting their own trade ahead of it. None of this requires any special access — just faster infrastructure and the willingness to pay higher transaction fees to jump the queue.
Several proposed fixes exist across the ecosystem (private transaction relays, batch auctions that settle many orders at one shared price instead of processing them one at a time), but none has become universal, which is exactly why episodes like this one keep recurring rather than getting solved once and for all.