# L2 Interop Working Group - Call #9 **May 28, 2025** - [Recording](https://youtu.be/fovRlynyqlc) - [Calendar invite for future calls](https://docs.google.com/forms/d/e/1FAIpQLSfMFEJmyVgjLuiipgxprEkiQXwwK3F_PfGbWvU8ZmV6e_ka0A/viewform) ### [Agenda](https://github.com/ethereum/pm/issues/1541) 1. Updates on ERC-7786 - crosschain messaging [OpenZeppelin] 2. [Interopolis](https://x.com/Interopolis) Summary 3. Open Intents Framework 2.0 updates [Hyperlane, LI.FI, OpenZeppelin, Across] 4. Interop Wallet v0 [presented by EF + Wonderland] 5. Interoperable addresses (aka chain-specific addresses) [Wonderland] 6. [Filler Vaults](https://ethresear.ch/t/filler-vaults-a-mechanism-to-deepen-cross-chain-liquidity-via-hyperliquid-style-vaults-for-intent-markets/22466): liquidity for intent markets [Socket] ## Call Notes *condensed notes below – watch the recording (above) for full discussion* ### TL;DR - 7786 crosschain messaging: - Goal: unify crosschain messaging through a standard interface - Spec finalized, continuing to make progress, and will be leveraging ERC-7930 style interoperable addresses - Interopolis event: - Goal: accelerate interop discussions and cross-team collaboration - Shared highlights from the first-ever Interopolis event in Athens: touched on 7786 discussions, wallet-led interop, resource locks, solver dynamics, and EF AMA. Thank you Interopolis + Sprinter team! - Open Intents Framework 2.0: - Goal: accelerate intents-based bridging - Working on a rewrite of the OIF, being led by a group of teams including contributions from Hyperlane, LIFI, OpenZeppelin, Across, and Uniswap. Goal remains the same: fast, easy, permissionless deployment of intents to all chains. Initial milestones will be shipped in next 1-2 months. - Interop Wallet v0: - Goal: accelerate wallet UX - A proof-of-concept wallet to showcase how emerging standards and recent interop work can help accelerate crosschain UX. Open initiative from the EF, Wonderland, and other contributors. Testnet only. Using Ambire wallet as the base. Phase 1 is focused on delivering seamless crosschain transfers leveraging interoperable addresses (7828). Phase 2 focused on integrating native privacy features. - Interoperable addresses (aka chain-specific addresses) - Goal: reduce friction around crosschain actions - Spec is close to being finalized (7828 + 7930). Looking for feedback on spec and address format (alice.eth@your-favorite-l2). Leveraging l2.eth as a second-level domain from ENS. See ENS temp check [here](https://discuss.ens.domains/t/temp-check-l2-eth-to-enable-chain-specific-addresses/20862). - Filler Vaults - Goal: scaling liquidity for intent markets - New [proposal](https://ethresear.ch/t/filler-vaults-a-mechanism-to-deepen-cross-chain-liquidity-via-hyperliquid-style-vaults-for-intent-markets/22466) from Socket team for scaling intent markets using “filler vaults” that decouple capital and execution. Can help to provide better coverage to long-tail chains and generally deeper liquidity. ### 1. Updates on ERC-7786 – Crosschain Messaging Presenter: Frangio (OpenZeppelin) Summary: - Recent technical calls have led to a frozen core spec for ERC-7786, focused on crosschain messaging with extensibility support. Key Points: - Discussions involved Wonderland, Espresso, Glacis. - Core design has been finalized and is now an open PR. - Adopting interoperable binary addresses (linked to ERC-7930). - Pending dependency: ERC-7930 finalization. - Future work includes gas payment interfaces for crosschain messages. Takeaway: Core spec is stable and pending adoption of interoperable binary address format. Next up: gas handling and further modular extensions. ### 2. Interopolis Summary Presenters: Ellie (Espresso), Jim (LI.FI) Summary: - Reflections from the Interopolis event; themes included 7786 adoption, UX expectations, and wallet-centric interop strategies. Key Points: - Apps’ interop priorities: speed, execution guarantees, user and liquidity access — security notably absent. - Wallets as interop enablers: focus should shift there. - EF alignment observed around signaling support, wallet R&D, and faster finality. - Event announcements: - Upcoming Interop Days @ ZuBerlin - Day 1 = near-term problems, led by Ellie - Day 2 = long-term interop vision, led by Luca - Jim’s Additions: - Desire for EF to signal support for standards. - Deep-dive sessions on:, Solver incentives (e.g. centralization vs. decentralization), Auction design, and resource locks (on-chain vs. MPC versions) ### 3. Open Intents Framework (OIF) 2.0 Updates Presenters: Josh (EF), Jim (LI.FI), Hart (Across) Summary: The OIF is evolving into a coordinated multi-team effort (Hyperlane, LI.FI, OpenZeppelin, Across) with new workstreams. Key Points: - Objective: open, neutral framework for deploying intents on all chains. - Workstreams: smart contracts, coordinator, UX components, etc. - Contract components will integrate compact (Uniswap), auction logic, expression modules, and crosschain verification. - Shared repo links, initial smart contract work underway. - Modularity and extensibility are key themes. ### 4. Interop Wallet v0 Presenter: Josh (EF), Titi (Wonderland) Summary: A proof-of-concept wallet for testnet UX R&D — not a production wallet — co-developed with Wonderland and based on Ambire. Key Points: - Goal: Validate standards and provide blueprint/reference implementation. - Phase 1: Crosschain UX focused — supports ERC-7828 (chain-specific addresses), adapter layer to plug into any interop infra. - Phase 2: Native privacy experience (privacy pools, shielded balances). - Phase 3: Advanced UX — unified balances, batch sends, further abstraction (leveraging 5792, 7811, etc.). Takeaway: A practical sandbox for crosschain UX innovation. Collaboration with wallet teams ongoing. Ambitious roadmap toward deep abstraction and privacy. ### 5. Chain-specific Addresses (ERC-7828 + ERC-7930) Presenter: Titi & Skele (Wonderland) Summary: Status update on interoperable address standards — human-readable (7828) and binary (7930). Key Points: - 7930 (binary format): Ready for draft merge; needed by 7786. - 7828 (human-readable): Working on registry for chain short names. - Short-term plan: fork Ethereum chainlist → multisig-governed ENS subdomain (l2.eth). - ENS subdomain used for resolving addresses like [email protected]. - SDK for wallets will abstract whether list is GitHub or on-chain. - Naming collisions and renaming (e.g., Optimism → OP Mainnet) addressed via multi-entry system rather than overwrites. Takeaway: Chain-specific addressing spec is close to finalization. Plan is pragmatic: start with GitHub list, migrate to on-chain list governed by ENS-style resolver. ### 6. Filler Vaults for Intent Liquidity Presenter: VC (Socket) Summary: New proposal for scaling intent markets using “filler vaults” that decouple capital and execution. Key Points: - Today: only few parties have both capital + skill. - Filler vaults separate strategy logic from funding, akin to Hyperliquid HLP vaults. - Vaults can support multiple strategies (e.g., varying latency tolerances). - Trust assumptions pluggable (ZKP, TEEs, multisig attestations). - Use case demoed with Across and Socket’s Switchboard. Takeaway: A practical path to scale intent fulfillment and solver participation. Socket invites teams to build on this infra with capital + infra support.