Ethereum L2 is set to transform back into "one chain"? EIL aims to create a seamless multi-chain experience.

To prevent users from being trapped in the dilemma of fragmented bridges, chains, and Wallets, the Ethereum Interop Layer aims to make multiple L2s appear as a single chain.

Ethereum has promised since its inception to create a global, permissionless, censorship-resistant computing platform. With the rise of Layer 2 (L2) solutions, the scalability issue has largely been resolved, allowing for faster transactions and lower fees, but it has also brought new challenges: too many chains, too fragmented, and a complicated experience. Now, the Ethereum Foundation's Account Abstraction team has proposed an entirely new initiative — the Ethereum Interop Layer (EIL), aiming to make multi-chain operations as simple and intuitive as operating on a single chain.

However, the article specifically states that this is a technical proposal put forward by the Ethereum Foundation's Account Abstraction team and does not represent the consensus position of the entire foundation. The Ethereum Foundation is a diverse and open organization that encompasses different viewpoints and technical approaches. These diverse discussions and experiments collectively drive the continuous evolution and strengthening of Ethereum.

Pain points of the multi-chain world: too many bridges, too much trust, too many steps.

Rollups (L2 chains) indeed make transactions cheaper and faster, but they also push users into a “multi-chain maze”:

Which chain is my token on?

Which bridge should I take to transfer from Arbitrum to Base, and then to Scroll?

Do I need to trust third-party bridges or relayers?

Wallet or DApp needs to manually integrate each chain?

For the average user, this is no longer about “using Ethereum”, but rather managing a bunch of different chains while risking trust in various intermediaries. This directly contradicts the original intention of blockchain's “decentralization”.

EIL Vision: Multiple L2s, yet feels like a single chain

The core idea proposed by the Ethereum Interop Layer is: to make all operations look as if they are using a single Ethereum. Imagine this:

Open the Wallet, select the asset, enter the address, and press “Send”.

The Wallet automatically determines which chain the token is on and which chain the other party is on, handling everything automatically in the background.

Minting NFTs, exchanging tokens, transferring funds, without needing to know which Rollup you or the other party is on.

User operations remain simple, and the technical complexity is entirely handled by the Wallet backend. This experience is akin to the “HTTP protocol” of blockchain: allowing various L2s to seamlessly connect like web servers, with users only needing to operate through a “browser” (Wallet).

Technical Foundation: Based on ERC-4337 and Trustless Manifesto

EIL is built on the account abstraction of ERC-4337, emphasizing that the following core values of Ethereum will not be sacrificed:

Self-custody: Users initiate transactions and control their assets.

Anti-censorship: No one can stop or delay your transactions.

Privacy Protection: No need to disclose IP or transaction details to intermediaries.

Verifiability: The transaction logic is on-chain or in an open-source Wallet, transparent and trustworthy.

EIL moves the trading logic from the server back on-chain and to the Wallet side, completely decentralizing. Users collaborate with “trustworthy but non-interactive” liquidity providers, without needing to trust any bridges, solvers, or other third parties.

What does a truly decentralized cross-chain experience look like?

Ethereum has completely transformed finance, moving from centralized exchanges (CEX) to decentralized exchanges (DEX). However, current cross-chain operations still resemble a “collage of multiple centralized exchanges.” The goal of EIL is to make cross-chain operations completely trustless and intermediary-free, just like using a DEX.

Here are a few practical scenarios:

Cross-chain transfer: Alice has USDC on Arbitrum and wants to transfer it to Bob on Base. She just needs to click a button, and the Wallet takes care of the rest.

Cross-chain Minting NFT: Alice has ETH on Arbitrum and Scroll, and wants to mint an NFT on Linea. The Wallet automatically merges funds and handles cross-chain gas, completing it with one click.

Cross-chain Swap: Alice discovered better liquidity on Optimism, she initiated the exchange directly from Arbitrum, and the Wallet handled all the bridging and jumping logic.

Users only see: “Send”, “Mint”, “Exchange” — just click.

The significance brought to the entire ecosystem

When cross-chain capability becomes a built-in feature of the Wallet, no longer relying on DApps to integrate one by one, everyone can benefit:

Wallet and DApp natively support multiple chains without the need for additional development.

With the new Rollup integration, all users can start using it immediately.

Developers focus on creating product experiences without worrying about the integration details between chains.

User experience returns to simplicity: one Wallet, one signature, operating the entire Ethereum universe.

The most important thing is: the trust-minimized and security model of Ethereum should not be compromised. What the Ethereum Interop Layer provides is a cross-chain, trustless, user-oriented future. It allows users to truly feel that no matter which L2 they use, they are still on “that Ethereum.”

This article asks whether Ethereum L2 should revert to “one chain”? EIL aims to create a seamless multi-chain new experience, first appearing in Chain News ABMedia.