The mempool is the dark forest where MEV predators hunt. On August 19, 2025, the 'Encrypt the Mempool' call convened to discuss a future where those predators go blind. But the data shows a more sobering reality: the cryptographic tools needed to seal the mempool do not yet exist. Let me be clear: this is not a deployment roadmap. It is a confession of the limits of current cryptography.
Last week, Vitalik Buterin’s address was hit by Jaredfromsubway.eth, a notorious MEV bot. The attack was not novel—sandwich trades on a high-profile target. But the timing was perfect. It coincided with the Ethereum Foundation’s push for EIP-8184, also known as LUCID, and the FOCIL inclusion list mechanism. The narrative is that Ethereum will encrypt the mempool to protect users from predatory bots. That narrative is dangerously incomplete.
Context: The Mempool as a Battleground
The public mempool is the heart of MEV. Every pending transaction is visible to searchers and builders who exploit order flow for profit. Current mitigations—private relays, private transaction channels—work by taking the mempool off the public grid. They create a trust dependency on the relay operator. They are not a protocol-level solution. They are band-aids.
In 2020, during DeFi Summer, I managed a $2M portfolio and saw firsthand how private relays created a two-tier system. Those with access to private channels paid less in MEV, but the protocol remained vulnerable. The encrypted mempool promises to fix this by making all transactions opaque until they are included in a block. The idea is elegant: commit-and-reveal, where the block builder submits a sealed block, then decrypts after inclusion. But elegance is not security.
Core: The Cryptographic Reality Check
Let’s talk about LUCID. The proposal is a commit-and-reveal scheme. The builder submits a transaction bundle without knowing its contents. The sender holds the decryption key until the block is sealed. Then the key is released. Simple? Not remotely.
Data doesn't lie, but the mempool does. According to the EIP-8184 authors, there is currently no known cryptographic construction that meets all the requirements for Ethereum-scale encrypted mempools. These requirements include: small public keys, non-interactive decryption, no trusted setup, practical ciphertext sizes, strong chosen-ciphertext security, and a credible path to post-quantum security. That is a laundry list of open problems. The authors themselves admit this.
Code is law, until it isn't. In this case, the law is being written in ciphertext, but the ciphertext cannot yet be written. The fallback for LUCID is to outsource key release to a third-party key publisher. This is not a cryptographic solution. It is a trust shift. The risk moves from the bot to the key publisher. The bot is replaced by a centralized gatekeeper. That is not an improvement; it is a different failure mode.
EIP-8105 proposes a directed trust graph. Registered providers can signal which other providers they trust. The incentive and penalty mechanisms are left off-chain. This is a social solution, not a technical one. It relies on reputation and voluntary compliance. In a bull market, trust is abundant. In a bear market, it collapses. The protocol cannot enforce honest behavior.
FOCIL (EIP-7805) is the inclusion list mechanism that will be prioritized for the Hegotá upgrade in 2027. It allows multiple validators to influence which transactions a block builder must include. This is the consensus-layer foundation for the encrypted mempool. But FOCIL itself does not encrypt anything. It only ensures that builders cannot exclude certain transactions. The encryption must come from LUCID or a similar proposal. The timeline is clear: the earliest possible deployment is 2027. And that is optimistic.
Contrarian: The Real Goal Is Not to Eliminate MEV
The prevailing narrative is that encrypted mempools will kill MEV. I disagree. The real goal is to raise the cost of attack. LUCID introduces a reserve fee mechanism: the encrypted portion of the block is limited to one-eighth of the gas limit, and a reserve fee is required. If the decryption fails, the fee is lost. If successful, most of the fee is refunded. This is a penalty for failure, but it cannot distinguish between a malicious attack and a honest network failure. The sender can be punished for a connectivity issue.
Volume lies. Liquidity speaks. The encrypted mempool does not reduce MEV; it changes who can capture it. The cost of sophisticated attacks increases, but so does the cost of legitimate transactions. The one-eighth gas limit on encrypted blocks means that high-volume protocols may struggle to use this feature without sacrificing throughput. The trade-off is stark: either accept the gas limit squeeze or rely on the unencrypted mempool for high-value transactions.
Moreover, the trust graph of EIP-8105 creates a new class of gatekeepers. The providers who are trusted will become the new arbiters of transaction inclusion. This is a form of centralization that the protocol cannot easily undo. In my 2017 ICO audit experience, I saw how seemingly minor trust assumptions snowballed into systemic risks. The same applies here.
Takeaway: The Road Ahead Is Not Paved with Cryptography Alone
The encrypted mempool is a necessary evolution for Ethereum, but it is not a silver bullet. The cryptographic community must solve the open problems first. The Hegotá upgrade in 2027 is the earliest realistic timeline. Until then, the private relay ecosystem will remain the de facto solution. The risk is that we rush a half-baked proposal into production, creating new vulnerabilities that are harder to detect because they are hidden in ciphertext.
Based on my audit experience, the most dangerous projects are the ones that promise to solve everything. The encrypted mempool promises to hide your trades from bots. But the data shows that the cryptographic tools are not ready. The real question is: can Ethereum afford to wait until 2029, when quantum computing may render today's encryption obsolete? Or will the market demand an imperfect solution now and accept the consequences?
Trust, but verify the genesis block. In this case, we cannot even verify the genesis of the encryption scheme. The prudent path is to watch the research, support the FOCIL rollout, but resist the urge to deploy LUCID until the cryptographic community has a working construction. The narrative is compelling, but the code is not yet law.
