Ethereum co-founder Vitalik Buterin said the role of layer-2 networks needs to be reconsidered as Ethereum’s main network continues to scale and transaction costs remain low.

In a post on X, Buterin said the original rollup-centric roadmap, which positioned layer-2s as the primary way Ethereum would scale, “no longer makes sense.” That roadmap envisioned layer-2s as secure extensions of Ethereum that would handle most transactions while inheriting Ethereum’s security guarantees, often described as “branded shards” of the network.

Layer 2s, such as Arbitrum, Optimism and Base, are offchain networks built on top of primary blockchains (Layer 1s) like Ethereum. The main purpose of these is to increase transaction speed and reduce transaction costs on the main network.

Think of Ethereum’s main network as a packed main hall at a conference. Space is limited, so getting in can be slow and expensive. Layer-2 networks act like overflow rooms, letting people participate and interact without crowding the main hall, while still staying connected to what’s happening there.

'You are not scaling Ethereum'

According to Buterin, two developments have challenged that original vision for Layer 2 networks.

First, progress among layer-2s toward later stages of decentralization has been slower and more difficult than expected. Second, Ethereum itself is now scaling directly on layer-1, with fees remaining low and gas limits expected to increase significantly in 2026.

Buterin wrote that scaling Ethereum should mean creating “large quantities of block space that is backed by the full faith and credit of Ethereum,” where activity is “guaranteed to be valid, uncensored, unreverted, untouched, as long as Ethereum itself functions.”

He argued that high-throughput chains connected to Ethereum through multisig-controlled bridges do not meet that definition. “If you create a 10000 TPS EVM where its connection to L1 is mediated by a multisig bridge, then you are not scaling Ethereum,” he wrote.

In his view, Ethereum no longer needs layer-2s to function as "branded shards" for the network. This means that, because Ethereum itself is scaling, layer-2 networks are no longer required to function as official extensions of Ethereum. He also noted that many layer-2s are “not able or willing” to meet the decentralization and security standards required by the model.

Buterin also noted that some layer-2s may intentionally choose not to move beyond “stage 1,” including for regulatory reasons.

In one example, he wrote that a project argued it may never decentralize further because “their customers’ regulatory needs require them to have ultimate control.” While he said that approach may be appropriate for those users, he added that such systems should not be described as scaling Ethereum.

“This may be doing the right thing for your customers. But it should be obvious that if you are doing this, then you are not 'scaling Ethereum' in the sense meant by the rollup-centric roadmap,” Buterin wrote.”

Instead, Buterin suggested viewing layer-2s as a spectrum of networks with different levels of connection to Ethereum, each offering different trade-offs. He said layer-2s should focus on providing value beyond basic scaling, such as privacy features, application-specific design, ultra-fast transaction confirmation, or non-financial use cases, and be clear with users about what guarantees they provide.

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