PayChain - Web3-Based Instant Salary Payment System 💰🚀

Overview

PayChain is a decentralized payroll system that enables real-time salary payments using smart contracts. Employees receive payments automatically every 30 minutes based on their work hours, directly into their MetaMask wallet.

Features

• Instant Salary Payments - Employees are paid every 30 minutes.
• Smart Contract Automation - Eliminates manual payroll processing.
• Crypto Payments - Salaries are paid in ETH or USDT.
• Transparent Records - All transactions are recorded on-chain.
• Easy Wallet Integration - Supports MetaMask.

Tech Stack

• Blockchain: Ethereum (or Polygon for lower gas fees)
• Smart Contracts: Solidity (ERC-20 based salary system)
• Frontend: React.js + Web3.js
• Backend: Node.js + Express.js
• Database: Firebase / MongoDB (for employer-employee records)
• Wallet Integration: MetaMask, WalletConnect

Installation & Setup

1️⃣ Clone the Repository

git clone https://github.com/codeypas/paychain.git
cd paychain

2️⃣ Install Dependencies

npm install

3️⃣ Start the Backend Server

cd server
npm install
npm run dev

4️⃣ Start the Frontend

cd client
npm install
npm start

5️⃣ Deploy Smart Contract

1. Install Hardhat:

   npm install --save-dev hardhat

2. Compile and Deploy:

   npx hardhat compile
   npx hardhat run scripts/deploy.js --network goerli

Smart Contract Setup: Getting Contract Address

After deploying your contract, retrieve the contract address:

Using Truffle:

cd paychain/truffle
truffle migrate --network development

Check the deployment output for the contract address.

Using Truffle Console:

truffle console --network development
let instance = await PayrollSystem.deployed()
instance.address

From Ganache UI:

1. Open Ganache
2. Navigate to "Contracts" tab
3. Find PayrollSystem contract
4. Copy the displayed contract address

Connecting MetaMask to Ganache

Step 1: Install MetaMask

1. Go to MetaMask Download
2. Install the extension
3. Create a new wallet

Step 2: Add Ganache as a Network in MetaMask

1. Open MetaMask
2. Click "Add Network"
3. Fill in the following details:
   • Network Name: Ganache Local
   • New RPC URL: http://127.0.0.1:8545
   • Chain ID: 1337
   • Currency Symbol: ETH
4. Click "Save"

Step 3: Import a Ganache Account to MetaMask

1. Copy the private key of an account from Ganache
2. In MetaMask, select Import Account
3. Paste the private key and click "Import"

Testing the Connection

Start your backend server:

cd paychain/server
npm run dev

Start your frontend application:

cd paychain/client
npm start

Open the app and test transactions:

1. Navigate to http://localhost:3000
2. Click "Connect MetaMask"
3. Use employer functions to add employees and deposit salary funds

Troubleshooting

MetaMask Not Connecting

• Ensure Ganache is running
• Verify MetaMask network settings
• Reset MetaMask (Settings > Advanced > Reset Account)

Contract Not Found

• Verify contract address in frontend/backend
• Ensure contract is deployed to Ganache

Transaction Errors

• Ensure sufficient ETH balance
• Use the correct account for operations

By following these steps, you can successfully set up and test PayChain locally before deploying to a testnet or mainnet.

Contributing

Feel free to contribute by forking the repo and submitting a pull request. 🚀

License

MIT License

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