Web3 Confessions

A privacy-preserving confession platform built with Fully Homomorphic Encryption (FHEVM) on Ethereum.

Share encrypted confessions anonymously on-chain with end-to-end encryption. Built using Zama's FHEVM technology for computation on encrypted data.

Features

• Fully Encrypted: Client-side encryption using FHEVM before blockchain submission
• Anonymous: Pseudonymous wallet-based identity with permanent privacy
• Encrypted Voting: Upvote mechanism without revealing vote counts
• On-Chain: Deployed on Ethereum Sepolia testnet
• Modern UI: Responsive design with glassmorphism effects
• Cross-Platform: Compatible with mobile, tablet, and desktop browsers

Architecture

web3-confessions/
├── contracts/              # Smart contracts (Hardhat)
│   ├── contracts/
│   │   └── ConfessionVault.sol
│   ├── test/
│   ├── scripts/
│   └── hardhat.config.ts
│
└── frontend/               # Next.js frontend
    ├── src/
    │   ├── app/           # App Router pages
    │   ├── components/    # React components
    │   ├── lib/           # Utilities & FHEVM wrapper
    │   └── store/         # Zustand state management
    ├── public/
    └── tailwind.config.ts

Quick Start

Prerequisites

• Node.js 18+ and npm
• MetaMask or compatible Web3 wallet
• Sepolia testnet ETH (get from faucet)

1. Clone the Repository

```bash git clone https://github.com/GadgetLeo/web3-confessions.git cd web3-confessions ```

2. Install Dependencies

```bash

Install root dependencies

npm install

Install contract dependencies

cd contracts npm install

Install frontend dependencies

cd ../frontend npm install ```

3. Configure Environment Variables

Contracts (.env)

```bash cd contracts cp .env.example .env ```

Edit `.env`: ```env SEPOLIA_RPC_URL=https://sepolia.infura.io/v3/YOUR_INFURA_KEY PRIVATE_KEY=your_private_key_here ETHERSCAN_API_KEY=your_etherscan_api_key ```

Frontend (.env.local)

```bash cd ../frontend cp .env.example .env.local ```

Edit `.env.local`: ```env NEXT_PUBLIC_CONFESSION_VAULT_ADDRESS=0x... # Will be set after deployment NEXT_PUBLIC_CHAIN_ID=11155111 NEXT_PUBLIC_FHE_PUBLIC_KEY=your_fhe_public_key NEXT_PUBLIC_SEPOLIA_RPC_URL=https://sepolia.infura.io/v3/YOUR_KEY NEXT_PUBLIC_WALLETCONNECT_PROJECT_ID=your_walletconnect_project_id ```

4. Deploy Smart Contract

```bash cd contracts

Compile contracts

npm run compile

Run tests

npm test

Deploy to Sepolia

npm run deploy:sepolia

Verify on Etherscan (optional)

npx hardhat verify --network sepolia <CONTRACT_ADDRESS> ```

The deployment script will automatically update the frontend's `.env.local` with the contract address.

5. Run Frontend

```bash cd frontend

Start development server

npm run dev ```

Open http://localhost:3000 in your browser.

Usage

Creating a Confession

1. Connect your Web3 wallet (MetaMask)
2. Click "Create Confession"
3. Type your confession (10-500 characters)
4. Click "Confess Anonymously"
5. Approve the transaction in your wallet
6. Your encrypted confession is now on-chain!

Upvoting

1. Click the heart icon on any confession
2. Approve the transaction
3. Vote is added to the encrypted counter

Viewing Confessions

• Home Feed: Browse all confessions
• Detail View: Click any confession for full view
• About Page: Learn how FHE works

Technology Stack

Smart Contracts

• Solidity ^0.8.24
• Zama FHEVM - Fully Homomorphic Encryption
• Hardhat - Development environment
• OpenZeppelin - Security libraries
• Sepolia - Ethereum testnet

Frontend

• Next.js 14 - React framework with App Router
• TypeScript - Type safety
• Wagmi + Viem - Ethereum interactions
• RainbowKit - Wallet connection UI
• Zustand - State management
• TailwindCSS - Styling
• Framer Motion - Animations
• fhevmjs - Client-side encryption

How FHE Works

Fully Homomorphic Encryption (FHE) allows computations on encrypted data without decryption.

1. Client-Side Encryption: Your confession is encrypted in your browser
2. On-Chain Storage: Encrypted data is stored on the blockchain
3. Encrypted Computation: Smart contract performs operations (like adding votes) on encrypted data
4. Privacy Preserved: No one ever sees the plaintext—not even validators

Plaintext → [Encrypt] → Ciphertext → [On-Chain Computation] → Encrypted Result
                                     ↓
                          No Decryption Needed!

Smart Contract Functions

Core Functions

• `submitConfession(bytes encryptedMessage)` - Submit encrypted confession
• `upvote(uint256 confessionId, bytes encryptedOne)` - Upvote with encrypted increment
• `getConfession(uint256 id)` - Get confession data (encrypted)
• `getConfessionCiphertext(uint256 id)` - Get raw ciphertext

Admin Functions (Owner Only)

• `updateRateLimit(uint256 newCooldown)` - Change submission cooldown
• `togglePause()` / `emergencyPause()` - Pause/unpause contract

View Functions

• `hasUserUpvoted(uint256 id, address voter)` - Check upvote status
• `getRemainingCooldown(address user)` - Get rate limit countdown

Design System

The UI follows a premium Web3 design language:

• Colors: Deep space backgrounds with purple-cyan gradients
• Glassmorphism: Frosted glass cards with backdrop blur
• Typography: Space Grotesk (headings), Inter (body)
• Animations: Smooth Framer Motion transitions
• Responsive: Mobile-first, scales to desktop

Development

Running Tests

```bash

Smart contract tests

cd contracts npm test

Test coverage

npm run coverage ```

Linting & Formatting

```bash

Frontend

cd frontend npm run lint

Format code

npx prettier --write . ```

Building for Production

```bash

Frontend

cd frontend npm run build npm start ```

Deployment

Contract Deployment

Contracts are deployed to Sepolia testnet. See deployment guide.

Frontend Deployment (Vercel)

1. Push code to GitHub
2. Import project in Vercel
3. Set environment variables in Vercel dashboard
4. Deploy automatically on push to `main`

Resources

• Zama FHEVM Docs
• FHEVM GitHub
• Wagmi Documentation
• Next.js Documentation
• RainbowKit Docs

Contributing

Contributions are welcome! Please follow these steps:

1. Fork the repository
2. Create a feature branch: `git checkout -b feature/amazing-feature`
3. Commit changes: `git commit -m 'Add amazing feature'`
4. Push to branch: `git push origin feature/amazing-feature`
5. Open a Pull Request

Code Style

• Follow existing code patterns
• Use TypeScript strict mode
• Add comments for complex logic
• Run tests before submitting PR

Security

• No Plaintext Storage: All sensitive data is encrypted
• Rate Limiting: Prevents spam submissions
• Audited Libraries: Uses OpenZeppelin standards
• Input Validation: Sanitizes all user inputs

⚠️ Testnet Only: This is a demonstration on Sepolia testnet. Do not use real funds.

License

MIT License - see LICENSE file for details

Acknowledgments

• Zama for FHEVM technology
• OpenZeppelin for security libraries
• Rainbow for wallet connection UI
• Vercel for frontend hosting

Support

• Issues: GitHub Issues
• Discussions: GitHub Discussions

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