DeFi Project Backend

Backend repository for our DeFi lending protocol project on Ethereum.

Before You Start

Please read GIT_RULES.md first and follow it during development. Frontend integration guide: FRONTEND_API.md

Targets

Basic:

• A lending pool where users can supply, withdraw, borrow, and repay
• Over-collateralization logic
• Interest rate model (kinked)
  • Dynamic interest rate model based on utilization rate
  • Accrue interest per block (lenders and borrowers)
• Oracle (simple fixed-price)

Bonus:

• Liquidation mechanism:
  • Allow a third party to liquidate a position when health factor < 1
  • Liquidation Spread/Bonus
• Flash Loan
• Real Oracle
• Advanced tokenomics: issue a governance token (like COMP or AAVE) as a reward for lenders/borrowers (liquidity mining)
• Analytics & UX

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Development Setup

• Use Remix (recommended)
• Use VS Code + Hardhat3 when needed

Repository Layout

• contracts/: Solidity contracts
• test/: automated tests
• scripts/: manual interaction scripts
• ignition/: deployment modules
• .vscode/: shared debug/task configs

VS Code + Hardhat Commands

Please use pnpm as your package manager. You can install it by:

npm install -g pnpm@latest-10

Install dependencies:

pnpm install

Compile contracts:

pnpm exec hardhat compile

Run Test

Start a local node:

pnpm exec hardhat node

Then run all test:

pnpm exec hardhat test --network localhost

Or only use TypeScript test:

pnpm exec hardhat test nodejs --network localhost

Or only use Solidity test:

pnpm exec hardhat test solidity --network localhost

Run a Script on a Fresh EVM

For example, to run scripts/deploy.ts:

pnpm exec hardhat run scripts/deploy.ts --network hardhatMainnet

Run a Script on Localhost

Start a local node:

pnpm exec hardhat node

Then run a TypeScript script on localhost. For example:

pnpm exec hardhat run scripts/play.ts --network localhost

Or connect Remix to your local node:

1. Open Remix or launch your Remix Desktop
2. Open Deploy & Run Transactions
3. Select Dev - Hardhat Provider
4. If needed, set the URL to http://127.0.0.1:8545