Community Blockchain - Web3 Disaster Relief Fund

rushi kesh

Completed work

Blockchain Developer

Software Engineer

Ethereum

Hardhat

Solidity

Cryptocurrency & Blockchain

🌍 Community Blockchain - Web3 Disaster Relief Fund

A decentralized disaster relief funding platform built with cutting-edge Web3 and privacy-preserving technologies. This project combines blockchain transparency with zero-knowledge privacy to create a secure, anonymous, and efficient disaster relief system.

🚀 Advanced Technologies Used

🔐 Zero-Knowledge Proofs (ZKP)

Anon Aadhaar ZK-SNARKs: Privacy-preserving identity verification

Nullifier System: Prevents double-spending and duplicate claims

Identity Privacy: Verify eligibility without revealing personal data

Cryptographic Proofs: Mathematical verification without data exposure

🌐 Web3 & Blockchain Stack

Ethereum Blockchain: Decentralized infrastructure

Solidity Smart Contracts: Immutable business logic

Ethers.js v6: Advanced blockchain interactions

Wagmi v2: React hooks for Ethereum

Web3Modal v4: Multi-wallet connectivity

Viem v2: Type-safe Ethereum client

Hardhat: Smart contract development framework

🛡️ Privacy & Security Technologies

Zero-Knowledge Circuits: Anon Aadhaar verification circuits

Cryptographic Nullifiers: Unique proof identifiers

Groth16 Protocol: Efficient ZK-SNARK implementation

Merkle Tree Proofs: Efficient membership verification

Poseidon Hashing: ZK-friendly hash function

⚛️ Frontend Technologies

Next.js 15: React meta-framework with SSR

React 18: Modern UI with concurrent features

TypeScript: Type-safe development

Tailwind CSS: Utility-first styling

React Query: Blockchain state management

🔗 Blockchain Infrastructure

JSON-RPC Providers: Blockchain communication

Smart Contract ABIs: Contract interfaces

Transaction Management: State updates and events

Gas Optimization: Efficient contract execution

Multi-network Support: Testnet and mainnet deployment

🏗️ System Architecture

Frontend Layer

Next.js Application
├── Components (UI/UX)
├── Pages (Routes)
├── Web3 Integration
└── State Management

Web3 Integration Layer

Wagmi Hooks
├── Wallet Connection
├── Contract Interactions
├── Transaction Management
└── Network Switching

Privacy Layer

Anon Aadhaar System
├── ZK Proof Generation
├── Identity Verification
├── Nullifier Management
└── Privacy Preservation

Blockchain Layer

Ethereum Network
├── DisasterFundPool Contract
├── AnonAadhaarVote Contract
├── Verifier Contracts
└── Access Control

🎯 Core Features

🔒 Privacy-First Design

Anonymous Donations: Contribute without revealing identity

Private Claims: Claim funds with ZK proof verification

Identity Protection: Verify eligibility without data exposure

Nullifier Prevention: Stop duplicate claims cryptographically

💰 Transparent Fund Management

On-chain Tracking: All transactions visible on blockchain

Real-time Updates: Live fund status and distributions

Immutable Records: Tamper-proof transaction history

Audit Trail: Complete funding lifecycle tracking

🎛️ Admin Controls

Project Authorization: Admin approves community projects

Status Management: Activate/deactivate funding campaigns

Access Control: Role-based permissions system

Governance: Decentralized decision making

🔐 Advanced Security

Smart Contract Security: Audited contract logic

Access Modifiers: Function-level permissions

Reentrancy Protection: Attack prevention mechanisms

Input Validation: Comprehensive data verification

🛠️ Development Setup

Prerequisites

Node.js 18+
npm or yarn
MetaMask wallet
Ethereum testnet ETH

Installation

# Clone repository
git clone https://github.com/rushikesh0022/community_blockchain.git
cd community_blockchain

# Install dependencies
npm install --legacy-peer-deps

# Setup environment variables
cp .env.local.example .env.local
# Add your contract addresses and keys

Smart Contract Development

# Navigate to contracts directory
cd contracts

# Compile contracts
npx hardhat compile

# Run tests
npx hardhat test

# Deploy to local network
npx hardhat node
npx hardhat run scripts/deploy.cjs --network localhost

# Deploy to testnet
npx hardhat run scripts/deploy.cjs --network sepolia

Frontend Development

# Start development server
npm run dev

# Build for production
npm run build

# Start production server
npm start

🧪 Zero-Knowledge Implementation

Anon Aadhaar Integration

// ZK Proof Generation
const proof = await generateAnonAadhaarProof({
  aadhaarData: userData,
  signal: walletAddress,
  fieldsToReveal: ["pincode"],
});

// Proof Verification
const isValid = await verifyAnonAadhaarProof(proof);

Privacy Workflow

Identity Verification: Generate ZK proof from Aadhaar data

Nullifier Creation: Unique identifier prevents reuse

Proof Submission: Submit proof to smart contract

Cryptographic Verification: Contract verifies without data access

Action Authorization: Execute claim/vote if proof valid

📋 Smart Contract Functions

DisasterFundPool.sol

// Project Management
function registerDisaster(string memory name, string memory description,
                         uint256 pincode, uint256 initialFunding) external onlyOwner

// Funding
function addFundsToDisaster(uint256 disasterId) external payable

// Claims with ZK Verification
function claimFunds(uint256 disasterId, uint256 nullifierSeed,
                   uint256 nullifier, uint256 timestamp,
                   address signal, uint256[4] calldata revealArray,
                   uint256[8] calldata groth16Proof) external

// Data Retrieval
function getDisasterDetails(uint256 disasterId) external view returns (...)

Zero-Knowledge Verification

// Verify Anon Aadhaar proof
modifier verifyAnonAadhaarProof(uint256 nullifierSeed, uint256 nullifier,
                               uint256 timestamp, address signal,
                               uint256[4] calldata revealArray,
                               uint256[8] calldata groth16Proof) {
    require(anonAadhaarVerifierAddr.verifyAnonAadhaarProof(
        nullifierSeed, nullifier, timestamp, signal, revealArray, groth16Proof
    ), "Invalid proof");
    _;
}

🌍 Network Configuration

Supported Networks

Local Development: Hardhat Network

Testing: Ethereum Sepolia Testnet

Production: Ethereum Mainnet

Contract Addresses

# Test Environment
DISASTER_FUND_POOL_TEST=0xB7696E510113C3F3063f869de7e5Ed49Bc1E8b5C
ANON_AADHAAR_VERIFIER=0x6bE8Cec7a06BA19c39ef328e8c8940cEfeF7E281

# Production Environment
DISASTER_FUND_POOL_PROD=0x...

🔄 Data Flow

Donation Flow

User → Connect Wallet → Select Project → Enter Amount →
Sign Transaction → Blockchain Update → UI Refresh

Claim Flow

User → Generate ZK Proof → Submit Claim → Contract Verification →
Nullifier Check → Fund Transfer → Event Emission

Admin Flow

Admin → Create Project → Set Parameters → Deploy to Blockchain →
Community Access → Fund Collection → Distribution Management

📚 Additional Documentation

Architecture Diagram - Complete system architecture

Blockchain Concepts - Detailed blockchain explanations

Smart Contracts - Contract documentation

🤝 Contributing

Fork the repository

Create feature branch (git checkout -b feature/amazing-feature)

Commit changes (git commit -m 'Add amazing feature')

Push to branch (git push origin feature/amazing-feature)

Open Pull Request

📄 License

This project is licensed under the MIT License - see the LICENSE file for details.

🚀 Deployment

Frontend Deployment

Vercel: Optimized for Next.js applications

Netlify: Alternative hosting platform

IPFS: Decentralized hosting option

Smart Contract Deployment

# Deploy to testnet
npx hardhat run scripts/deploy.cjs --network sepolia

# Verify on Etherscan
npx hardhat verify --network sepolia CONTRACT_ADDRESS

🔮 Future Enhancements

Multi-chain Support: Deploy on Polygon, BSC, etc.

DAO Governance: Community-driven project approval

Advanced Analytics: ML-powered fraud detection

Mobile App: React Native implementation

Layer 2 Integration: Lower transaction costs

🛟 Support

Issues: GitHub Issues

Discussions: GitHub Discussions

Documentation: Check the docs folder for detailed guides

Built with ❤️ using cutting-edge Web3 and Zero-Knowledge technologies # or yarn install

## Environment Setup

This project requires environment variables for configuration.

1. **Root Directory (`.env`):**
Create a `.env` file in the project root by copying the example:

```bash
cp .env.local.example .env
```

Update the following variables in the `.env` file:

- `NEXT_PUBLIC_ANON_AADHAAR_CONTRACT_ADDRESS`: The deployed Anon Aadhaar Verifier contract address (often a standard one, check Anon Aadhaar docs). The example uses `6bE8Cec7a06BA19c39ef328e8c8940cEfeF7E281`.
- `NEXT_PUBLIC_VOTE_CONTRACT_ADDRESS_PROD`/`_TEST`: The deployed `AnonAadhaarVote` contract address. You will get this after deployment.
- `NEXT_PUBLIC_DISASTER_FUND_POOL_ADDRESS_PROD`/`_TEST`: The deployed `DisasterFundPool` contract address. You will get this after deployment.
- `NEXT_PUBLIC_PROJECT_ID`: Your WalletConnect Cloud project ID. Get one from [cloud.walletconnect.com](https://cloud.walletconnect.com/).
- `NEXT_PUBLIC_RPC_URL`: The RPC URL for the network you are deploying to (e.g., Sepolia, Holesky).
- `PRIVATE_KEY`: The private key of the wallet you will use for _deployment only_. **Handle with extreme care.**

2. **Contracts Directory (`contracts/.env`):**
Create a `.env` file within the `contracts` directory:
```bash
cp contracts/.env.example contracts/.env # Assuming you create an example file there
# or manually create contracts/.env
```
Add the following variables:
- `PRIVATE_KEY`: The private key of the account you'll use to deploy the contracts. **This is critical and should be kept secret.**
- `NEXT_PUBLIC_RPC_URL`: The RPC URL for the network (e.g., Holesky, Sepolia).
- Optionally, add API keys if needed for block explorers (e.g., `ETHERSCAN_API_KEY`).

## Contract Deployment

The smart contracts (`AnonAadhaarVote`, `DisasterFundPool`) are managed using Hardhat.

1. **Navigate to the contracts directory:**

```bash
cd contracts
```

2. **Install contract dependencies (if not already done by root `npm install`):**

```bash
npm install
# or
yarn install
```

3. **Compile the contracts:**

```bash
npx hardhat compile
```

4. **Deploy the contracts:**
Ensure your `contracts/.env` file is correctly set up with your `PRIVATE_KEY` and `NEXT_PUBLIC_RPC_URL`.
Run the deployment script:

```bash
npx hardhat run scripts/deploy.cjs --network <your_network_name>
```

Replace `<your_network_name>` with the network defined in your [`hardhat.config.js`](contracts/hardhat.config.js) (e.g., `sepolia`, `holesky`, `localhost`).

5. **Update `.env`:**
After successful deployment, the script ([`contracts/scripts/deploy.cjs`](contracts/scripts/deploy.cjs)) will output the addresses of the deployed `DisasterFundPool` and `AnonAadhaarVote` contracts. Copy these addresses and paste them into the corresponding `NEXT_PUBLIC_VOTE_CONTRACT_ADDRESS_...` and `NEXT_PUBLIC_DISASTER_FUND_POOL_ADDRESS_...` variables in the root `.env` file.

## Running the Application

1. **Navigate back to the root directory:**

```bash
cd ..
```

2. **Run in development mode:**

```bash
npm run dev
# or
yarn dev
```

Open [http://localhost:3000](http://localhost:3000) in your browser.

3. **Build for production:**

```bash
npm run build
# or
yarn build
```

4. **Start the production server:**
```bash
npm run start
# or
yarn start
```

## Linting

To check code style:

```bash
npm run lint
# or
yarn lint