In a post on X, Ethereum co-founder Vitalik Buterin stated that the goal of achieving faster withdrawal times is even more critical than achieving “Stage 2” L2 decentralization, noting that it will help Ethereum L1 remain the dominant economic center of the ecosystem.
“Amazing to see so many major L2s now at stage 1,” Buterin wrote in response to a post on X that reported that all six rollups, Base, Optimism, Unichain, Scroll, Ink, and Kinto, affected by the Stage 1 requirements changes, have performed the necessary upgrades and are now fully compliant.
Buterin said, “The next goal we should shoot for is, in my view, fast (<1h) withdrawal times, enabled by validity (aka ZK) proof systems. I consider this even more important than stage 2.”
For users and liquidity providers, withdrawing assets from L2 to L1 can take up to a week unless intermediaries are used. Buterin argues that this lag not only burdens users but also creates pressure to adopt bridging solutions with weaker trust models like multisig wallets or MPC (multi-party computation), which run counter to Ethereum’s decentralization ethos.
Ethereum should move from optimistic to validity proofs
According to Buterin, optimistic proofs were historically favored because zero-knowledge (ZK) proofs, also known as validity proofs, were too immature and expensive. But that reality is quickly changing. ZK proof technology has improved significantly over time, enabling Ethereum-compatible ZK rollups that can verify L2 execution with greater speed and security.
The Ethereum co-founder referenced resources like ethproofs.org, which now track advancements in ZK proof development.
Buterin laid out a potential path to transition toward faster withdrawals using a hybrid “2-of-3” proof system that combines ZK, optimistic (OP), and trusted execution environment (TEE) components. The idea is that a proof system would only need agreement from two of the three approaches to validate a withdrawal.
Buterin also noted that one of the final bottlenecks to achieving fast settlement times will be the gas cost of submitting large ZK proofs on-chain.
Ethereum’s push for 12-second settlement and cross-L2 fluidity
Buterin’s long-term vision goes beyond one-hour withdrawals. He believes that with further improvements in proof aggregation, combining many ZK rollup proofs into one, Ethereum could enable L1 settlement of multiple rollups every slot (approximately every 12 seconds).
This would allow for near-instant native asset movement across L2s via the L1, effectively eliminating the need for centralized bridge solutions or long exit windows.
In such a scenario, Ethereum L1 wouldn’t just be a security anchor; it would also serve as a high-speed settlement hub across the L2 ecosystem. This architecture would further cement Ethereum’s role as the economic center of its own universe, where most tokens, protocols, and financial activity remain tied to the L1 while scaling occurs on top.
Reducing L2 withdrawal times is not just a UX improvement; it’s a foundational shift in Ethereum’s architecture. As proof systems improve and aggregation becomes standard, the Ethereum L1 could become a high-speed financial layer capable of real-time settlement across a growing network of trustless L2s.
