GPv2Settlement Contract

The GPv2Settlement contract serves as CoW Protocol’s core infrastructure, inheriting from GPv2Signing, ReentrancyGuard, and StorageAccessible to enable batch settlements and order validation. Source: src/contracts/GPv2Settlement.sol License: LGPL-3.0-or-later Solidity: >=0.7.6 <0.9.0

State Variables

Immutable

Variable	Type	Description
`authenticator`	`GPv2Authentication`	Determines solver authorization
`vault`	`IVault`	Balancer Vault for fund management
`vaultRelayer`	`GPv2VaultRelayer`	Enables vault interactions on behalf of users

Storage

Variable	Type	Description
`filledAmount`	`mapping(bytes => uint256)`	Tracks per-order fill amounts to prevent over-filling

Primary Functions

settle()

Executes batch orders at uniform clearing prices with pre/intra/post-settlement interactions.

function settle(
    IERC20[] calldata tokens,
    uint256[] calldata clearingPrices,
    GPv2Trade.Data[] calldata trades,
    GPv2Interaction.Data[][3] calldata interactions
) external nonReentrant onlySolver;

swap()

Matches orders directly against Balancer V2 pools for optimized single-pool trades.

function swap(
    IVault.SingleSwap calldata swap,
    GPv2Trade.Data calldata trade
) external nonReentrant onlySolver returns (int256);

invalidateOrder()

Allows order owners to revoke on-chain orders by invalidating the order UID.

function invalidateOrder(bytes calldata orderUid) external;

Storage Cleanup

Gas refund functions for expired orders:

function freeFilledAmountStorage(bytes[] calldata orderUids) external;
function freePreSignatureStorage(bytes[] calldata orderUids) external;

Settlement Execution Flow

Security Protections

All orders include a validTo timestamp checked on execution
Filled amount tracking prevents over-filling
Limit price validation ensures trades respect order parameters
Solver authorization restricts settlement access via onlySolver modifier
nonReentrant modifier prevents reentrancy attacks

Contracts

Hooks Trampoline

Composable CoW

Contracts SDK

Flash Loan Router

GPv2Settlement

GPv2Settlement Contract

State Variables

Immutable

Storage

Primary Functions

settle()

swap()

invalidateOrder()

Storage Cleanup

Settlement Execution Flow

Security Protections

​GPv2Settlement Contract

​State Variables

​Immutable

​Storage

​Primary Functions

​settle()

​swap()

​invalidateOrder()

​Storage Cleanup

​Settlement Execution Flow

​Security Protections

GPv2Settlement Contract

State Variables

Immutable

Storage

Primary Functions

settle()

swap()

invalidateOrder()

Storage Cleanup

Settlement Execution Flow

Security Protections