SCALE: Smart Contract Access Logic for EVM

Demo

About

PROBLEMS What Problems Are We Solving? - Compliance is done via UI only. Smart contracts are still ungated. - Data on-chain is expensive and is slow to publish. Why Do These Problems Exist? - Changing data (e.g. growing sanction list), but the blockchain is immutable - Requires massive data on-chain (e.g. 10,000+ sanction addresses) SOLUTIONS Background / Context - Molecule Protocol: Smart Contract ACL (Access Control List) Middleware - Use case: Compliance! ETH Global 2020 (KYC), ETH Global 2022 (AML) What Are The Solutions? - MP is future-proof: delegated ACL allows add or remove logic anytime - Publish once, use by all smart contracts, no (huge) duplicate on-chain data What’s Implemented for the Hackathon? - Mass data publishing on-chain - Allow list implementation for subscription payments

How it's made

(1) MASS DATA PUBLISHING: Layer 1 vs. Layer 2 benchmark - Ethereum max batch size: 25. 10,000 sanction list => 400 tranctions $$$$$ - Layer 2: size > 500. Deployed on Scroll, Base (Optimism), Polygon, Filecoin See the screencap for the benchmark of different layer 2 blockchains. We deployed the sanction lists on different layer 2s--Scroll, Base (OP Stack), Polygon, and Filecoin EVM--and tested each chain's maximum batch transaction size. (2) SUBSCRIPTION PAYMENT To take advantage of the lower gas fees on layer 2s, we implemented a modified version of EIP-5643 (Subscription NFTs). - To allow subscribers to see their subscription, we decide to mint a standard ERC721 to subscriber wallets - To avoid confusion, each user can only own 1 token, and the tokenID will be irrelevant - Expiry needs to be tracked - Sanctioned wallet addresses are not allowed. Gated by using Molecule AML with US and EU sanction lists checked - The subscription contract is implemented as a Molecule smart contract so it can be composable with other controllers