Ethereum co-founder Vitalik Buterin recently highlighted the critical role of proof system reliability in advancing Layer 2 rollups to full decentralization, known as Stage 2. His comments follow a proposal by Daniel Wang, CEO of Taiko Labs, who introduced a new label, “Battle Tested”, to evaluate the maturity and resilience of rollup technologies.
Additionally, Daniel Wang, speaking on the social platform X, raised concerns about how some Layer 2 rollups are being categorized. While certain rollups meet decentralization and feature-based requirements to qualify as Stage 2, Wang argued that these projects may still rely on unproven code that hasn’t faced high-pressure, real-world scenarios. To address this, he proposed that only rollups that have operated stably on the Ethereum mainnet for over six months, with more than $100 million in total value locked (TVL), including $50 million in ETH and major stablecoins, should be considered “Battle Tested.”
Wang emphasized that this status wouldn’t be permanent. Any major code upgrade would reset the evaluation period, as each new version would need to prove itself under live conditions again. He also mentioned that Taiko, an Ethereum Layer 2 solution, aims to move toward Stage 2 using only “Battle Tested” code. He even suggested the idea of creating a separate Ethereum-based rollup testbed for this purpose.
In response, Vitalik Buterin added that reaching Stage 2 isn’t just about decentralization. The quality and security of the underlying proof system are equally important. He presented a simplified model to help decide when it’s safe for a rollup to move to the next stage. This model evaluates the likelihood of failure among council members who help secure the protocol, considering both technical errors and real-world risks like coercion or hacking.
Buterin also pointed out that even well-designed decentralized systems can be undermined if they rely on weak or untested proof systems. He advised combining multiple independent proof systems to lower the risk of failure and increase resilience.
According to Ethereum’s L2BEAT framework, Stage 2 rollups should run entirely on smart contracts and cryptographic proofs, with no reliance on centralized parties. They must allow anyone to verify transactions, resolve disputes on-chain, and withdraw assets directly to Layer 1 without needing approval.
However, Buterin concluded that adopting Stage 2 too early, especially with a fragile proof system—poses the greatest danger to a rollup’s integrity. True maturity, he argued, must come from both strong decentralization and high-quality, proven security systems.