Zcash Cofounder Backs Vitalik's Quantum Ethereum Plan

Big Minds Debate EthereumETH+1.26%'s Quantum Future

How will Ethereum stay safe when powerful quantum computers arrive? That big question sparked a detailed debate across social media platform X on October 19, 2026.

Top leaders in crypto jumped into the conversation. The discussion featured Ethereum cofounder Vitalik Buterin, Zcash cofounder Eli Ben-Sasson, Delphi Labs General Counsel Gabriel Shapiro, and the team at venture firm a16z crypto.

Together, they tackled a core dilemma facing blockchain builders: should Ethereum rely on lattice-based cryptography or stick to hash-based designs to protect user funds?

The Debate: Lattice vs. Hash-Based Cryptography

The conversation started when a16z crypto published a post making the case for lattice-based cryptography.

In their post, a16z crypto argued that Ethereum's planned hash-only signature design relies heavily on SNARK recursion. They claimed this choice brings heavy coordination overhead, a larger bug surface, and unestablished security.

The venture firm suggested that relying purely on hash-based cryptography might seem safer on paper, but it could ultimately result in more brittle systems.

Why AI Makes Lattice Math Risky

Eli Ben-Sasson, cofounder of Zcash and CEO of StarkWare, strongly disagreed with the argument from a16z crypto.

Ben-Sasson pointed out that lattice cryptography has a rich mathematical structure. He warned that this structure makes it a prime target for future artificial intelligence (AI) tools to attack and break.

Gabriel Shapiro of Delphi Labs also weighed in against a16z crypto. He stated that the current hash-first approach remains the best overall path for Ethereum.

Shapiro suggested that if lattice cryptography ever proves to be AI-secure, Ethereum could still support it for individual accounts and wallets using a precompile. Meanwhile, sticking to hash-based math lets Ethereum's core consensus run at full speed.

Vitalik Buterin Outlines the Ideal Roadmap

Ethereum cofounder Vitalik Buterin voiced full agreement with Shapiro's perspective.

Buterin explained that Ethereum can support diverse cryptographic preference without cluttering the blockchain network. He highlighted proposal 8288 as the cleanest route forward.

Under this setup, users can generate whatever signature they want locally on their own devices. That signature gets converted into a STARK proof and processed through a STARK aggregator machine.

"The ideal route to support everyone's cryptography is imo through 8288. You make whatever signature you want locally, then STARK it, and then it gets included through the stark aggregator machine. Don't need any calldata onchain. Ethereum can then never add a new precompile again," Buterin noted.

Seeing Buterin's detailed solution, Eli Ben-Sasson voiced his complete support on X, posting: "Agree, this is the right way for Ethereum."

Why Ethereum Must Prepare for Quantum Computers

Most proof-of-stake blockchains depend on large validator sets to confirm transactions. Validators vote on each block by signing it.

To keep the network running fast, Ethereum uses BLS signatures. BLS signatures allow tens of thousands of validator votes per slot to be combined into a single group element.

While BLS signatures are efficient today, they have a major flaw: they are not post-quantum safe. Future quantum computers could potentially crack BLS math, putting network security at risk.

The Plan: Lean Consensus and Native Account Abstraction

To fix this vulnerability, Ethereum's Lean consensus roadmap aims to completely replace BLS signatures with quantum-resistant hash-based signatures, such as variants of Winternitz signatures.

The network will then use STARKs to aggregate those hash signatures smoothly behind the scenes.

Earlier this year, Buterin explained that the full quantum-defense strategy combines protocol-layer recursive signatures with proof aggregation.

A key part of this strategy is native account abstraction through EIP-8141. EIP-8141 provides a framework for transaction validation, execution, and gas payments, allowing regular wallets to use custom, quantum-safe signature algorithms without changing Ethereum's core code.