Rain is an on-chain prediction-markets platform on Arbitrum One. Its products include Rain Vaults, non-custodial strategy vaults for trading Rain markets, and USDR, a multi-collateral over-collateralized stablecoin. Visit rain.trade.
Zealynx is reviewing USDR (Rain Dollar) as an external contractor engagement for Composable Security, in a three-week review. USDR is a multi-collateral, over-collateralized stablecoin on Arbitrum One adapted from MakerDAO's Multi-Collateral Dai, backed by a basket of USDT, USDC and RAIN and built around one rule enforced at every block: the protocol's maximum possible loss can never exceed its stable reserves. The scope covers the core ledger and collateral adapter, the oracle security module and price converter, the peg stability module, reserve accounting and the solvency engine, the liquidation stack with its circuit breaker, and the timelocked governor. The report will be published when the engagement closes.
Zealynx reviewed Rain Vaults as an external contractor engagement for Composable Security. Rain Vaults are non-custodial strategy vaults for Rain prediction markets on Arbitrum One: a manager trades, depositors hold pro-rata shares, and the design goal is that the manager can never withdraw depositor funds, only trade through an allowlisted set of Rain market functions whose positions and proceeds accrue back to the vault. The review covered the VaultFactory and RainVault contracts: share accounting and NAV, the FIFO withdrawal queue and permissionless force-unwind, manager trading and delegated trading keys, and fee minting. The report is being prepared for publication.
When someone asks “did Carlos really audit Rain?”, this is the page to send them. Every engagement where Carlos participated as a contractor, listed in one place, with the public artifacts and the partner firm that ran the audit.