'Almost Like Satoshi Knew Something': Adam Back Criticizes Ethereum's Early Design

Blockstream CEO and early Bitcoin pioneer Adam Back has criticized Ethereum's early design decisions, arguing that the network's developers ignored warnings when they departed from Bitcoin's architecture. His remarks, made in an X post on October 10, came after Ethereum researchers warned this week that artificial intelligence could break the signatures securing Bitcoin and Ethereum "in months, not years" in the worst case — well before quantum computers arrive.

Back was particularly critical of Ethereum's early developers, describing them as inexperienced and saying they "reimplemented around an obviously broken architecture despite attempts to warn them.

In his X post, Back wrote:

@seal_kiman @UtxoSaint It's almost like Satoshi knew something about distributed systems (or network / p2p programming) as the UTXO model is well-designed for avoiding them. .eth's were young, naive, no experience/wisdom, reimplemented around an obviously broken architecture. Tried to warn them 🤷‍♂️ — Adam Back (@adam3us) October 10, 2026

Back's perspective is rooted in Bitcoin's earliest lineage: Hashcash, the proof-of-work system he created in 1997, is cited among the handful of prior works referenced in Satoshi Nakamoto's Bitcoin whitepaper.

Back Defends Satoshi's UTXO Choice

The Blockstream CEO suggested that Bitcoin's pseudonymous creator, Satoshi Nakamoto, chose the Unspent Transaction Output (UTXO) model for the Bitcoin network — a decision Back said reflected a deeper understanding of distributed systems and peer-to-peer network design.

"It's almost like Satoshi knew something about distributed systems," Back said in support of Bitcoin's UTXO model.

In this context, UTXO stands for the "Unspent Transaction Output" model, which works like physical cash: discrete coins or outputs are spent and new ones are created. Blockchains such as Bitcoin and Cardano use this design.

Ethereum does not use UTXO. Instead, it employs an account-based model — similar to a traditional bank ledger — in which each user or smart contract holds a persistent balance and state that updates directly with each transaction. That divide between the two models has been a recurring point of debate since Ethereum's 2015 launch.

While Ethereum currently relies on accounts, its researchers have proposed experimental frameworks to introduce optional UTXO-style features. One example is Ethereum Improvement Proposal EIP-8141, which introduces a new transaction type (0x06, or Frame Transactions) designed to achieve native account abstraction and post-quantum readiness. How experimental proposals like this one progress through Ethereum's open improvement process is one thread to watch as researchers reassess the cryptography both networks depend on.

What Happened?

Ethereum researcher Justin Drake, in an X post on Wednesday, told the crypto industry to begin preparing for "bunker mode," warning that artificial intelligence could find a way to break the mathematics protecting Bitcoin and Ethereum wallets in the worst case "in months, not years."

Accordingly, Drake urged large holders to start gradually moving their funds to fresh addresses.

Ethereum co-founder Vitalik Buterin weighed in on Drake's assessment, saying he would not recommend that anyone scramble to move funds to new wallets at the moment, while adding that the risk from AI-accelerated mathematics should be taken seriously.

"I don't recommend anyone scramble to move their funds to new wallets today. But we should take the risks to cryptography from AI-accelerated math seriously, and minimize our exposure to not just quantum-vulnerable cryptography but also potentially AI-vulnerable cryptography," Buterin wrote on X.

Cryptographic upgrades must ultimately be delivered through each chain's existing architecture, meaning the early design choices now under debate have a direct bearing on how Bitcoin and Ethereum can respond to quantum- and AI-era risks.