crane-balancer

name	crane-balancer
description	This skill should be used when the user asks about "Balancer V3 integration", "Balancer pool", "weighted pool", "constant product pool", "BPT token", "Balancer vault", "rate provider", or needs to create or interact with Balancer V3 pools using Crane's DFPkg and service libraries.
license	MIT

Crane Balancer V3 Integration

Crane provides comprehensive Balancer V3 integration including pool DFPkgs, vault awareness, authentication, and test infrastructure.

Components

Component	Location	Purpose
BalancerV3WeightedPoolDFPkg	pool-weighted/BalancerV3WeightedPoolDFPkg.sol	Deploy weighted pools (80/20, custom weights)
BalancerV3ConstantProductPoolDFPkg	pool-constProd/BalancerV3ConstantProductPoolDFPkg.sol	Deploy 50/50 constant product pools
BalancerV3VaultAwareRepo	vault/BalancerV3VaultAwareRepo.sol	Vault dependency injection
BalancerV3PoolRepo	vault/BalancerV3PoolRepo.sol	Pool metadata storage
BalancerV3WeightedPoolRepo	pool-weighted/BalancerV3WeightedPoolRepo.sol	Weight storage
BalancerV3AuthenticationRepo	vault/BalancerV3AuthenticationRepo.sol	Pool authentication
TestBase_BalancerV3Vault	test/bases/TestBase_BalancerV3Vault.sol	Full vault deployment
ERC4626RateProviderFacetDFPkg	rateProviders/ERC4626RateProviderFacetDFPkg.sol	Rate provider for yield tokens

Pool Types

Crane supports two Balancer V3 pool types:

Type	DFPkg	Use Case
Weighted	BalancerV3WeightedPoolDFPkg	Custom weight pools (80/20 ETH/TOKEN)
Constant Product	BalancerV3ConstantProductPoolDFPkg	50/50 pools (x*y=k)

Quick Start: Deploy Weighted Pool

import {IBalancerV3WeightedPoolDFPkg, BalancerV3WeightedPoolDFPkg} from "@crane/contracts/protocols/dexes/balancer/v3/pool-weighted/BalancerV3WeightedPoolDFPkg.sol";
import {TokenConfig, TokenType} from "@balancer-labs/v3-interfaces/contracts/vault/VaultTypes.sol";

contract MyFactory {
    BalancerV3WeightedPoolDFPkg public poolDFPkg;

    function deployPool(
        IERC20 tokenA,
        IERC20 tokenB
    ) external returns (address pool) {
        TokenConfig[] memory tokenConfigs = new TokenConfig[](2);
        tokenConfigs[0] = TokenConfig({
            token: tokenA,
            tokenType: TokenType.STANDARD,
            rateProvider: IRateProvider(address(0)),
            paysYieldFees: false
        });
        tokenConfigs[1] = TokenConfig({
            token: tokenB,
            tokenType: TokenType.STANDARD,
            rateProvider: IRateProvider(address(0)),
            paysYieldFees: false
        });

        uint256[] memory weights = new uint256[](2);
        weights[0] = 80e16;  // 80%
        weights[1] = 20e16;  // 20%

        pool = poolDFPkg.deployPool(
            tokenConfigs,
            weights,
            address(0)  // No hooks
        );
    }
}

Token Configuration

Balancer V3 uses TokenConfig for pool tokens:

TokenConfig({
    token: IERC20(tokenAddress),
    tokenType: TokenType.STANDARD,      // or TokenType.WITH_RATE
    rateProvider: IRateProvider(address(0)),  // or actual rate provider
    paysYieldFees: false               // true for yield-bearing tokens
})

Token Types

Type	Use Case	Rate Provider
STANDARD	Regular ERC20 tokens	None required
WITH_RATE	Yield-bearing tokens (ERC4626)	Required

Rate Providers for ERC4626

Deploy rate providers for yield-bearing tokens:

import {ERC4626RateProviderFacetDFPkg} from "@crane/contracts/protocols/dexes/balancer/v3/rateProviders/ERC4626RateProviderFacetDFPkg.sol";

// Deploy rate provider for ERC4626 vault
IRateProvider rateProvider = erc4626RateProviderDFPkg.deployRateProvider(IERC4626(vaultAddress));

// Use in token config
TokenConfig({
    token: IERC20(address(vault)),
    tokenType: TokenType.WITH_RATE,
    rateProvider: rateProvider,
    paysYieldFees: true
})

DFPkg Initialization

BalancerV3WeightedPoolDFPkg requires initialization:

struct PkgInit {
    IFacet balancerV3VaultAwareFacet;
    IFacet betterBalancerV3PoolTokenFacet;
    IFacet defaultPoolInfoFacet;
    IFacet standardSwapFeePercentageBoundsFacet;
    IFacet unbalancedLiquidityInvariantRatioBoundsFacet;
    IFacet balancerV3AuthenticationFacet;
    IFacet balancerV3WeightedPoolFacet;
    IVault balancerV3Vault;
    IDiamondPackageCallBackFactory diamondFactory;
    address poolFeeManager;
}

AwareRepo Pattern

import {BalancerV3VaultAwareRepo} from "@crane/contracts/protocols/dexes/balancer/v3/vault/BalancerV3VaultAwareRepo.sol";

// Initialize during deployment
BalancerV3VaultAwareRepo._initialize(vault);

// Access in operations
IVault vault = BalancerV3VaultAwareRepo._balancerV3Vault();

Storage Slots

Repo	Slot
BalancerV3VaultAwareRepo	"protocols.dexes.balancer.v3.vault.aware"
BalancerV3PoolRepo	"protocols.dexes.balancer.v3.pool"
BalancerV3WeightedPoolRepo	"protocols.dexes.balancer.v3.pool.weighted"
BalancerV3AuthenticationRepo	"protocols.dexes.balancer.v3.authentication"

Testing

import {TestBase_BalancerV3Vault} from "@crane/contracts/protocols/dexes/balancer/v3/test/bases/TestBase_BalancerV3Vault.sol";

contract MyTest is TestBase_BalancerV3Vault {
    function setUp() public override {
        super.setUp();
        // vault, router, batchRouter available
        // erc4626RateProviderDFPkg available
    }

    function test_deployPool() public {
        TokenConfig[] memory configs = new TokenConfig[](2);
        configs[0] = standardTokenConfig(dai);
        configs[1] = standardTokenConfig(usdc);

        uint256[] memory weights = new uint256[](2);
        weights[0] = 50e16;
        weights[1] = 50e16;

        // Deploy and test pool
    }
}

File Organization

contracts/protocols/dexes/balancer/v3/
├── pool-weighted/
│   ├── BalancerV3WeightedPoolDFPkg.sol
│   ├── BalancerV3WeightedPoolFacet.sol
│   ├── BalancerV3WeightedPoolTarget.sol
│   ├── BalancerV3WeightedPoolRepo.sol
│   └── WeightedTokenConfigUtils.sol
├── pool-constProd/
│   ├── BalancerV3ConstantProductPoolDFPkg.sol
│   ├── BalancerV3ConstantProductPoolFacet.sol
│   └── BalancerV3ConstantProductPoolTarget.sol
├── vault/
│   ├── BalancerV3VaultAwareRepo.sol
│   ├── BalancerV3VaultAwareFacet.sol
│   ├── BalancerV3PoolRepo.sol
│   ├── BalancerV3PoolFacet.sol
│   ├── BalancerV3AuthenticationRepo.sol
│   └── BalancerV3AuthenticationFacet.sol
├── rateProviders/
│   ├── ERC4626RateProviderFacetDFPkg.sol
│   ├── ERC4626RateProviderFacet.sol
│   └── ERC4626RateProviderTarget.sol
├── utils/
│   ├── TokenConfigUtils.sol
│   └── BalancerV38020WeightedPoolMath.sol
└── test/bases/
    ├── TestBase_BalancerV3.sol
    ├── TestBase_BalancerV3Vault.sol
    └── TestBase_BalancerV3_8020WeightedPool.sol

Additional Resources

Reference Files

• references/balancer-services.md - Detailed patterns and examples