Contracts Overview
CoW Protocol (Gnosis Protocol v2) is a decentralized trading protocol that leverages batch auctions and coincidence of wants to provide optimal trade execution.
Core Contracts
GPv2Settlement
The central orchestration contract handling order validation, batch settlements, and Balancer Vault coordination.
- Validates order signatures and parameters
- Executes batched trades at uniform clearing prices
- Manages pre/intra/post-settlement interactions
- Inherits from
GPv2Signing, ReentrancyGuard, and StorageAccessible
GPv2VaultRelayer
A relayer for Balancer Vault interactions and token transfers.
- Transfers tokens from user accounts to the settlement contract
- Executes batch swaps through Balancer pools
- Restricted to settlement contract access only
GPv2AllowListAuthentication
Manages solver authorization via an allowlist mechanism.
- Maintains a mapping of authorized solver addresses
- Managed by a designated manager role
- Supports proxy-based upgradeability
Key Libraries
| Library | Purpose |
|---|
| GPv2Order | EIP-712 order hashing and UID management |
| GPv2Trade | Trade encoding/decoding with compact flag representation |
| GPv2Interaction | Settlement interaction hooks for arbitrary contract calls |
| GPv2Signing | Multi-scheme signature verification (EIP-712, eth_sign, EIP-1271, PreSign) |
Deployment Order
- Authentication contract is deployed first (with proxy)
- Settlement contract is deployed with the authenticator address
- VaultRelayer is auto-deployed by the settlement contract constructor
Three-Phase Settlement
Security Features
- Reentrancy protection via
ReentrancyGuard
- Solver authorization via
onlySolver modifier
- Order validation including signature, expiry, and price checks
- Interaction restrictions preventing calls to VaultRelayer
Gas Optimizations
- Assembly usage for low-level operations
- Storage refunds for expired order cleanup
- Compact trade encoding reducing calldata costs
- Memory reuse across settlement operations
Last modified on March 4, 2026
