Solana should reintroduce a public mempool, researcher says

A Solana researcher identified that the network’s top sandwich bot was pocketing millions of dollars a day from sandwich attacks

article-image

Artwork by Crystal Le

share


This is a segment from the Lightspeed newsletter. To read full editions, subscribe.


It seems like conversations about sandwich attacks on Solana — where advanced traders front-run and back-run trades to extract value at the expense of unsophisticated traders — come and go every few weeks with little resolution. Most people agree sandwiching is bad, but there’s not yet consensus on how the problem can be solved.

The discourse flared up again this week after the Solana researcher Ben Coverston posted on social media that the network’s top sandwich bot, dubbed arsc, was pocketing millions of dollars-worth of tokens per day from sandwich attacks. Coverston predicted that if current trends hold, arsc would become Solana’s largest staker within 1-2 years. Interestingly, one of the researcher’s proposed fixes included the reintroduction of a “mempool” staging area for transactions — which Jito got rid of earlier this year in hopes of preventing sandwiching.

Sandwich attackers exploit slippage — the gap between a trade’s expected and executed price. They front-run the target transaction by placing their own trade first, which shifts the price in their favor. Then, they back-run the same transaction by placing another trade immediately after, locking in a financial win off of the manipulated price movement. As a result, the original trader often ends up with a worse execution price, effectively subsidizing the attacker’s profit.

This is a form of maximal extractible value (MEV) where sandwichers extract value from Solana blocks at the expense of less sophisticated users. Solana has taken a number of actions meant to prevent sandwiching in recent months. In March, Solana infrastructure company Jito Labs got rid of its public mempool, which was a staging area where transactions could be arranged to create MEV revenue for validators.

Sandwiching validators then set up their own private mempools, and the attacks continued. Two months later, the Solana Foundation stopped offering financial help to validators who were participating in private mempools. In September, Jito blacklisted a group of private mempool validators from participating in its stake pool, which is a large pile of staked SOL Jito’s software delegates.

The criticism of the Solana Foundation and Jito’s blacklist-the-bad-guys strategy is that it’s essentially playing whack-a-mole: Blacklisted validators can always spin up a new validator and resume sandwiching. 

That’s what’s interesting about Coverston’s proposal, which he expanded upon in a blog post. The privatization of mempools has reduced the number of validators executing sandwich attacks, but the few who remain, like arsc, are staking their substantial profits back into their own operations. This has led to a concerning centralization of staked Solana within a handful of nefarious validators.

To counter this, Coverston suggests re-enabling a public mempool. While this move might make sandwiching more widespread, it could also foster competition among validators executing these strategies. The increased competition would help distribute MEV profits more evenly, preventing a single group of validators from disproportionately accumulating stake — and power — on the network.

This would essentially be a reversal from Solana’s anti-sandwiching strategy over the past nine months.

To put this all in perspective though, sandwiching may not really matter in the long run. High-frequency trading strategies that are ascendent in the US equities market are basically meant to sandwich attack other traders, Blockworks Research’s Ryan Connor pointed out. That hasn’t stopped equities trading volumes from climbing to all-time highs.


Get the news in your inbox. Explore Blockworks newsletters:

  • Blockworks Daily: The newsletter that helps thousands of investors understand crypto and the markets, by Byron Gilliam.
  • Empire: Start your morning with the top news and analysis to inform your day in crypto.
  • Forward Guidance: Reporting and analysis on the growing intersection of crypto and macroeconomics, policy and finance.
  • 0xResearch: Alpha directly in your inbox. Market highlights, data, degen trade ideas, governance updates, token performance and more.
  • Lightspeed: Built for Solana investors, developers and community members. The latest from one of crypto’s hottest networks.
  • The Drop: For crypto collectors and traders, covering apps, games, memes and more.
Tags

Upcoming Events

Industry City | Brooklyn, NY

TUES - THURS, JUNE 24 - 26, 2025

Permissionless IV serves as the definitive gathering for crypto’s technical founders, developers, and builders to come together and create the future.If you’re ready to shape the future of crypto, Permissionless IV is where it happens.

Old Billingsgate

Mon - Wed, October 13 - 15, 2025

Blockworks’ Digital Asset Summit (DAS) will feature conversations between the builders, allocators, and legislators who will shape the trajectory of the digital asset ecosystem in the US and abroad.

recent research

Research

article-image

Ledn CIO John Glover discusses using the Elliot Wave Theory to predict BTC price action

article-image

The SEC’s new crypto task force met Friday, but agreement on “defining security status” remains elusive

article-image

Star Atlas CEO explains why he’s against the narrative that crypto game devs should just focus on making a “fun game” first.

article-image

With mainnet now live, Nillion looks to bring privacy-preserving compute to Web3

article-image

A wild BearWhale has also been spotted more than 10 years after the original

article-image

Stablecoins haven’t yet gone mainstream, and at least one roadblock can be solved when regulatory clarity is finalized