# L2 Interop Working Group - Call #10 **June 25, 2025** - [Recording](https://youtu.be/UojELYVU2eY) - [Calendar invite for future calls](https://docs.google.com/forms/d/e/1FAIpQLSfMFEJmyVgjLuiipgxprEkiQXwwK3F_PfGbWvU8ZmV6e_ka0A/viewform) ### [Agenda](https://github.com/ethereum/pm/issues/1591) 1. Biconomy presentation: enabling gasless 1-click ethereum (Mislav) - [slides](https://docs.google.com/presentation/d/1IZkXIgsSMC9Xe5fkUIMJS5xKQsUSZNI69OzttoJUMQI/edit?slide=id.p#slide=id.p) 3. [Kohaku](https://github.com/ethereum/wallet-poc) wallet: interop/acc + privacy prototype (EF + Wonderland) 4. Based rollups, shared sequencing, & how they fit into interop/acc - Brecht (Taiko), Donnoh (L2BEAT), Drew (Fabric) ## Call Notes *condensed notes below – watch the recording (above) for full discussion* ### TL;DR - Enabling gasless, 1-click ethereum - presentation from Biconomy to show how you can leverage "verifiable multichain scripts" to do complex, crosschain actions with one gasless click - play with a demo at defi-demo.biconomy.io - [Kohaku](https://github.com/ethereum/wallet-poc) wallet: - prototype wallet focused on accelerating interop, crosschain UX, and privacy - developed by teams from the EF and Wonderland (fork of Ambire wallet). Testnet-only. - v1: - interoperable addresses (7828 + 7930) - crosschain sends using Open Intents Framework & Across 7683 - universal balances - v2 coming soon w/ built-in 0xbow Privacy Pools - Based rollups + shared sequencing - overview of based rollups + interop benefits from Drew (github.com/eth-fabric) - Brecht + Taiko on preconfirmations and their latest work - Donnoh (L2BEAT) w/ his perspective and a call for more work on shared sequencing --- ## AI summary ### 1. Biconomy: Gasless One-Click Ethereum **Presenter:** Mislav (VP Product, Biconomy) **Links:** - [Docs](https://docs.biconomy.io) - [Blog Post](https://blog.biconomy.io/eip-7702-from-transactions-to-composable-multi-chain-programs-verfiable-scripting-on-the-evm/) - [Slide Deck](https://docs.google.com/presentation/d/1IZkXIgsSMC9Xe5fkUIMJS5xKQsUSZNI69OzttoJUMQI/edit?slide=id.p#slide=id.p) ### Summary - Introduced verifiable multichain scripts: calldata-encoded programs that execute on-chain across multiple chains. - **Super Transactions**: - Merkle root of function calls signed once by the user - Enables multi-chain execution with a single signature - **Gas Abstraction**: - Cross-chain gas sponsorship (e.g. USDC on Arbitrum pays for gas on Base) - **Orchestrator Accounts**: - Scripts execute in isolated sandbox accounts using ERC-20 `approve` or EIP-7702/7715 delegation ### Key Features - Composable batch calls with **dynamic parameter injection** - Fully on-chain execution logic; relayers post calldata but don’t need trust - Uses `abstract.js` TypeScript DSL for scripting (in development) - Network is moving toward **permissionless relayers** with staking and slashing ### Demo Highlight - User signed one transaction to: - Transfer USDC from Arbitrum - Supply ETH on Base to Morpho pool - All without holding ETH or gas on either chain --- ## 2. [Kohaku](https://github.com/ethereum/wallet-poc) Wallet: Interop + Privacy Prototype **Leads:** Ethereum Foundation + Wonderland **Links:** - [EF Notes](https://notes.ethereum.org/@rudolf/kohaku-wallet) - [Wonderland Notion](https://defi-wonderland.notion.site/Interoperable-Addresses-Wallet-2019a4c092c780d09070fc06a1043303) ### Overview - Prototype fork of **Ambire** wallet - Experimental wallet for: - Cross-chain UX (interop) - Native privacy features - Standards prototyping (ERCs 7683, 7828, 7930) ### v1 Features - **Interoperable Addresses** (ERC-7828, 7930) - Human-readable: `[email protected]` - Binary-encoded fallback - **Cross-Chain Send** via [Open Intents Framework](https://github.com/ethereum/oif-spec) (ERC-7683) - **Universal Balances**: - e.g. aggregate ETH/USDC across chains into a single user-facing balance - Future: support transfers/swaps using abstracted balances ### Privacy Roadmap - Integrated [Privacy Pools](https://privacypools.com/) - Key flows: - Wallet-native “Private Mode” - Compliance gate (delayed entry, vetting window) - Session key support (EIP-7702) ### ENS + Chainlist Migration - Moving GitHub-maintained chain metadata on-chain via ENS: `l2.eth` - ENS DAO temperature check complete; waiting for controller upgrade to submit executable proposal --- ## 3. Based Rollups, Shared Sequencing, and Interop **Speakers:** Drew (Fabric), Brecht (Taiko), Donnoh (L2BEAT) **Link:** [eth-fabric composability guide](https://eth-fabric.github.io/website/education/composability) ### What are Based Rollups? - Rollups that delegate sequencing to Ethereum validators - Enable L1 ↔ L2 synchronous composability - Bring L1-level censorship resistance and infra access to L2s ### Benefits - Inherits L1 liquidity and tooling (e.g., Chainlink, USDC) - Simplifies app deployment (one deploy → access from L1 + all based L2s) - Improves decentralization and regulatory resilience - Enables experimentation with custom sequencing rules ### Status & Infrastructure - Live Based Rollups: Taiko, Facet - Commit Boost: lets validators offer fast preconfirmations - Signal Boost: rollups keep own sequencer but can request L1-based inclusion as needed ### Implementation Milestones - Preconfirmations: - Already live on [Taiko Hekla testnet](https://hekla.taiko.xyz/) - Block confirmations every 2s with reduced cost - Real-time proving progressing via ZKVM projects - Preconfirmers moving from whitelisted → permissionless ### Challenges - Real-time proving not yet available - UX suffers from slow L1 slot time - L1 cost (blob fees) remain high for frequent rollup publication - Shared sequencing infra (e.g., Conduit, Superchain) still early ---