# L2 Interop - Simplified Roadmap *Intended as a high-level summary. Many of the below items can be done in parallel.* ## Goals: 1. Cross-chain sends: - Users should be able to send assets from any chain to any other chain in less than 3 slots (of the slower chain) - eg. 12 * 3 = 36 seconds to or from L1, 2 * 3 = 6 seconds from optimism to arbitrum... 2. Chain-specific payment requests: - Users should have an easy and standardized way to make a request of type: "send me X tokens of type Y on chain Z". - Note: this supports 2 primary use cases: (i) person-to-person, and (ii) dapps requesting funds. 3. Updateable keys: - Users should be able to easily update the keys that control their smart contract wallet. - Short-term: updates should naturally propagate across chains - Medium-term: keystore -> updates only happen in one place 4. Verify chain directly: - Short-term: users should be able to verify the chain they are interacting with, rather than trust RPC providers. - Long-term: create general-purpose p2p network, so in principle no RPC providers required at all ## Roadmap: 1. Cross-chain sends: - [ERC-7785](https://ethereum-magicians.org/t/erc-7785-onchain-registration-of-chain-identifiers/21299): On-chain configs - Need ERC to define common interface for on-chain config (solidity ABI the wallets would call) - Eventually include specification of state proof verification rules: [ERC-3668](https://eips.ethereum.org/EIPS/eip-3668) - [ERC-7828](https://github.com/ethereum/ERCs/pull/735): chain-specific addresses - [ERC-7683](https://eips.ethereum.org/EIPS/eip-7683): cross-chain intents - [RIP-7755](https://ethereum-magicians.org/t/rip-7755-contract-standard-for-cross-l2-calls-facilitation/20776): cross-chain calls - Shared bridges (down the road) 2. Chain-specific payment requests: - ERC to define 4. Updateable Keys: - Keystore wallets - [See Scroll design](https://hackmd.io/@haichen/keystore) - [RIP-7728](https://ethereum-magicians.org/t/rip-7728-l1sload-precompile/20388): L1SLOAD precompile - [REMOTESTATICCALL](https://github.com/ethereum-optimism/ecosystem-contributions/issues/76) - Cross-L2-replayable account state updates 5. Verify chain directly: - Cross-chain light clients - integrated into wallets - [ERC-3668](https://eips.ethereum.org/EIPS/eip-3668): secure off-chain data retrieval