DeFi API Guide

Build decentralized finance applications with the best DeFi protocols. Compare lending, borrowing, and swapping APIs.

What is DeFi API?

DeFi (Decentralized Finance) APIs allow developers to integrate decentralized finance protocols into their applications. These include lending platforms, decentralized exchanges, yield aggregators, and more.

DeFi Protocol Categories

🦄 Decentralized Exchanges (DEX)

  • Uniswap
  • Curve Finance
  • PancakeSwap
  • Balancer

🏦 Lending Platforms

  • Aave
  • Compound
  • Yearn Finance
  • MakerDAO

📈 Yield Aggregators

  • Yearn
  • Convex
  • Pickle Finance
  • Beefy

⚡ Perpetual Trading

  • GMX
  • dYdX
  • Perpetual Protocol
  • Gains Network

Top DeFi APIs

Uniswap SDK

The most popular DEX protocol. Great for token swaps and liquidity pools.

  • Free: Yes (gas fees apply)
  • Networks: Ethereum, Arbitrum, Optimism, Polygon
  • Documentation: docs.uniswap.org

Aave Protocol

Leading lending protocol for earning interest and borrowing assets.

  • Free: Yes (gas fees apply)
  • Networks: Ethereum, Polygon, Arbitrum, Avalanche
  • Documentation: docs.aave.com

1inch API

DEX aggregator that finds the best swap rates across multiple protocols.

  • Free Tier: 1M requests/month
  • Networks: 20+ chains
  • Documentation: 1inch.io/docs

Curve API

Specialized in stablecoin and wrapped asset swaps with low slippage.

  • Free: Yes (gas fees apply)
  • Networks: Ethereum, Arbitrum, Avalanche
  • Documentation: curve-docs.readthedocs.io

Building with DeFi APIs

Common Use Cases

  • Token Swap Bot: Automatically swap tokens at best rates
  • Yield Optimizer: Automatically move funds to highest yield
  • Lending Interface: Build UI for depositing and borrowing
  • Portfolio Tracker: Track DeFi positions across protocols
  • Arbitrage Bot: Find price differences across DEXs

DeFi API Considerations

Important Factors

  • Gas Costs: DeFi transactions require ETH for gas
  • Slippage: Large trades may experience price impact
  • Smart Contract Risk: Protocols may have vulnerabilities
  • Impermanent Loss: Consider when providing liquidity
  • API Rate Limits: Check limits before building high-volume apps

Getting Started

Basic Integration Steps

  1. Choose your blockchain network (Ethereum, Polygon, etc.)
  2. Set up wallet with private key management
  3. Install SDK or use JSON-RPC provider (Alchemy, Infura)
  4. Integrate smart contracts using web3.js or ethers.js
  5. Test on testnet (Sepolia, Mumbai) before mainnet
  6. Monitor gas prices and optimize transactions