Unchained Ep. 953 Summary

"ETH’s HTTP Moment? How Ethereum Interop Layer Hopes to Fix L2 Fragmentation"

Host: Laura Shin
Guests: Marissa Posner & Yoav Weiss (Ethereum Foundation, Account and Chain Abstraction Team)
Date: November 20, 2025
Location: DevConnect, Buenos Aires, Argentina

Episode Overview

In this episode, Laura Shin interviews Marissa Posner and Yoav Weiss from the Ethereum Foundation about the new Ethereum Interop Layer (EIL)—a protocol designed to solve the fragmentation and friction plaguing cross-rollup activity on Ethereum. Drawing on metaphors like “islands” and “HTTP for blockchains,” they discuss how EIL aims to deliver a smooth user experience across Ethereum L2s, removing trust assumptions, minimizing dependence on bridges, and empowering wallets and users for seamless multi-chain transactions.

Key Discussion Points and Insights

1. The Problem: L2 Fragmentation and Friction

• Rollups as “Islands”
  Current Ethereum scaling via layer-2 (L2) rollups has led to each rollup feeling like an isolated “island”—cheap, abundant blockspace within, but user-hostile friction when transacting across them.
• The Bridge User Experience
  Cross-chain actions typically require using bridges, which means waiting, hoping, and extra steps:

  “You need to bridge ETH to the other chain so that you can pay for gas... there’s a lot of friction, especially if you’re using a hardware wallet. So all of this friction, it doesn’t feel like using one chain.” – Yoav Weiss [01:46]

2. Introducing the Ethereum Interop Layer (EIL)

• What Is EIL?
  A protocol designed to make cross-rollup (L2-to-L2) transactions on Ethereum feel as seamless as using one chain, without new trust assumptions (i.e., no extra parties to trust compared to Ethereum itself).

  “We came up with this protocol that does not add trust assumptions... it’s going to feel like one chain. You’re able to transact on multiple chains as if it's a single chain.” – Yoav Weiss [06:02]

• Solving for Abundant, Seamless Blockspace
  EIL enables the user to sign one operation for any number of involved chains, with wallets handling all the underlying mechanics, reducing UX pain.

3. The Role of Trust Assumptions

• Why Trustlessness Matters
  Marissa and Yoav argue that every added trust assumption (e.g., third-party bridge operators, unverified RPCs) creates new ways users can be harmed.

  “When you trust someone blindly, you open yourself up to getting hurt from them… with interoperability you’re actively increasing that space…” – Marissa Posner [08:59]

• Bridges as a Security Weak Point
  Many current interoperability solutions force users into new, often opaque trust relationships. EIL’s design counters this risk by avoiding extra intermediaries.

4. How EIL Works: Pushing Interop to the Wallet

• Account-Based (Wallet) Interop
  All interop logic and coordination lives within the user’s own wallet, not on a server or relay.

  "We are pushing the logic into the wallet. The wallet should be the user agent as opposed to trusting a third party… All the logic lives in your own wallet.” – Yoav Weiss [13:41]

• Cross-Chain Gas Payment Using Paymasters
  EIL leverages ERC-4337 “Paymaster” contracts to let users pay gas fees on other chains without needing ETH natively on each. Liquidity providers supply cross-chain assets via atomic swaps backed by vouchers, with no knowledge of the user's full transaction:

  “...when we were designing EIL we wanted to avoid [the solver having user info]... the liquidity provider... doesn't know where I'm going after, all it knows is I need this amount of money and it can choose to give me the gas or not.” – Marissa Posner [18:32]

• Illustrative Analogy
  Bus (solver-based model): driver knows your destination, can censor you.
  Gas station (EIL model): provider knows only you need fuel, not your journey.

5. Comparison With Intents-Based/“Solver” Protocols

• Difference from Intents/NEAR Intents
  Intent-based protocols ask a solver (an outside party) to interpret your goal—adding trust and interpretative risk.

  “With EIL, you describe exactly what you want to do, wallet-side. You’re not giving a black box your goal to interpret.” – Yoav Weiss [19:55]

• Composability at the Wallet Level
  While intent protocols attempt to match users to best execution, EIL focuses on precise, trustless operations where the wallet orchestrates, not a remote server.

6. Analogy: EIL as HTTP for Ethereum

• HTTP Moment for Blockchains
  Pre-HTTP, the internet was siloed (FTP, telnet, IRC). HTTP allowed composability, uniting different services in a single user flow.

  “Ethereum feels a lot like the pre-HTTP internet. What changed it was the web—HTTP. ... EIL can do the same for Ethereum.” – Yoav Weiss [26:31]

• Implication:
  Standardized, cross-chain operations, greater developer/design space, and ultimately a much more user-friendly ecosystem.

7. Scope and Limitations

• L2-Only
  EIL covers Ethereum L2s (and other EVM chains settling to Ethereum L1). Does not generalize to all alt-L1s due to lack of a universal shared state.

  “You need to have a single shared source of truth... Ethereum has that, L1.” – Yoav Weiss [29:25]

• Not for Multiparty Transactions
  EIL excels at single-user, multi-step flows. Not suitable for cases like Coincidence-of-Wants DEXes (e.g., CoWSwap) requiring multiple parties’ coordination or information asymmetry:

  “EIL is perfect for single user transactions. When you have a case of multiparty... EIL isn’t a fit for that at all.” – Marissa Posner [31:29]

• No True Cross-Chain Contract Composability
  User flows can involve multiple contracts, but direct synchronous cross-chain calls between contracts remain impossible due to L2 finality constraints.

8. Security and Implementation

• Account Abstraction Risks/Benefits
  Account abstraction creates new interfaces and features—but as with all smart contracts, users must ensure they use secure, audited contracts. Adds crucial flexibility (e.g., quantum resistance) and access controls.
• EIL Requires No L2 Coordination or Hard Forks
  It’s “just” smart contracts—permissionlessly deployable on any EVM rollup.
• Live on Testnet; Mainnet ETA 2026
  Protocol docs are public; code undergoing security review and testing. Hackathons encouraged.

9. Impact: What EIL Unlocks

• User Experience Revolution

  “The moment that you remove the concept of what a chain is... you’ve just made it so much easier to transact on chain and you’ve removed so much friction.” – Marissa Posner [37:43]

• Defi and Dapp Supercharger
  The “money legos” vision of DeFi and composability returns—now truly cross-chain.

• Potential for Broader Use Cases
  Anticipated use cases include multi-step asset management (lend, swap, stake across L2s), batch workflows, and more, limited only by what users and devs imagine—much like the unforeseen evolution of the web post-HTTP.

10. Bridges, Security, and the Future

• Bridges Not Obsolete, But Reframed
  Canonical bridges remain for rollup settlement; unsafe third-party bridges can be avoided.

  “With bridges... not all bridges are created equal... The way to fix that is [by showing] if you’re going to use this bridge, this is the risk you are taking.” – Yoav Weiss [45:39]

• Evaluation Tools for Users
  Tools like L2Beat (“L2BIT”) are key for surfacing trust risks to users when moving assets or interacting cross-chain.

• Trustless Manifesto
  The Ethereum Foundation published a “Trustless Manifesto” to re-anchor interoperability work in core Ethereum values of trust minimization and transparency.

Notable Quotes & Memorable Moments

• On the Friction of the Current State:

  “Every rollup is an island and the bridges between them are complex... we want to have an experience of having one chain but with abandoned block space.” – Yoav Weiss [10:17]

• On Trust Assumptions:

  “A way that someone can hurt you, rug you, or do something bad to you... in a lot of times we don’t realize how many trust assumptions there are in what we’re doing online.” – Marissa Posner [08:59]

• On the “HTTP” Parallel:

  “Ethereum feels a lot like the pre-HTTP internet. ...With the HTTP protocol you can have an application that spans across multiple servers... EIL can do the same for Ethereum.” – Yoav Weiss [26:31]

• On Reducing Reliance on Third-Party Servers:

  “The notion that you’re unable to access your crypto because Cloudflare is down, it doesn’t make sense to me. That's not why we are building Ethereum.” – Yoav Weiss [31:55]

• On User Empowerment:

  “We empower the wallet... Now the wallet itself can run any multi-chain operation no matter how complex... the application doesn't need to worry about plumbing.” – Yoav Weiss [33:53]

Important Timestamps

• [01:46] – Yoav Weiss on user friction of cross-L2 transactions
• [06:02] – Yoav Weiss introduces EIL and its core purpose
• [08:59] – Marissa Posner on trust assumptions and why they matter
• [13:41] – EIL logic inside wallets, not third-party servers
• [18:32] – Marissa’s “liquidity as gas station” analogy
• [26:31] – Yoav’s “HTTP for Ethereum” analogy
• [29:25] – Why EIL is L2-specific (Ethereum settlement as source of truth)
• [31:29] – Use cases not suitable for EIL
• [33:53] – Wallet as the new "browser" for decentralized apps
• [37:43] – Marissa on expected impact for user activity on Ethereum
• [45:39] – On the changing role and transparency of bridges
• [47:23] – Marissa on the Trustless Manifesto and Ethereum values

Final Thoughts

The Ethereum Interop Layer’s debut may mark a paradigm shift in multi-chain UX, lowering barriers, reducing trust risks, and letting users traverse (and compose across) L2s as easily as they once navigated the early web. The “HTTP moment for blockchains” could be on the horizon, and this discussion is a window into the motivations, design, and aspirations behind the innovation.

For more technical docs and experimentation:

• Ethereum Interop Layer Protocol Documentation
• Trustless Manifesto

Episode produced by Laura Shin and Unchained podcast team.