Overview

Integrate directly with Gearbox contracts from your Solidity code. This guide covers on-chain integration patterns for smart contract developers.

Prerequisites

• Solidity 0.8.x experience

• Familiarity with interface-based contract interaction

• Understanding of ERC-20 and common DeFi patterns

What You'll Learn

Topic	Description
Contract Discovery	Find any protocol address via AddressProvider
Credit Operations	Interact with CreditFacade and CreditManager
Multicall Encoding	Build and execute multicalls in Solidity
Pool Operations	Deposit, withdraw, and read pool state

Guide Structure

1. Contract Discovery - AddressProvider, ContractsRegister, navigation patterns

2. Credit Operations - ICreditFacadeV3, ICreditManagerV3 interfaces

3. Multicalls - MultiCall struct encoding, adapter calls

4. Pool Operations - IPoolV3 deposit/withdraw, ERC-4626 functions

Key Interfaces

// Core interfaces you'll use
import {IAddressProviderV3} from "@gearbox-protocol/core-v3/contracts/interfaces/IAddressProviderV3.sol";
import {ICreditFacadeV3} from "@gearbox-protocol/core-v3/contracts/interfaces/ICreditFacadeV3.sol";
import {ICreditManagerV3} from "@gearbox-protocol/core-v3/contracts/interfaces/ICreditManagerV3.sol";
import {IPoolV3} from "@gearbox-protocol/core-v3/contracts/interfaces/IPoolV3.sol";

When to Use Solidity Integration

Use Case	Recommended
On-chain protocol integration	Yes
Building adapters	Yes
Composable strategies	Yes
Backend services	No (use SDK Guide)
Frontend applications	No (use SDK Guide)

For TypeScript/JavaScript applications, see the SDK Guide.

Architecture Understanding

For conceptual background on how Gearbox works:

• Credit Suite Architecture - How Credit Managers, Facades, and Configurators work together

• Pool Architecture - Lending pools and ERC-4626 compliance

• Multicall System - How multicalls execute and validate