TALA - Trust is Code API

A zero-trust time capsule system for Indian exam, tender, and evidence workflows built with Go and Next.js.

Features

• 🔐 Secure File Encryption: AES-256-GCM encryption client-side and on-device
• ⏰ Time-Locked Capsules: Pre-programmed unlock schedules
• ✍️ Wallet Integration: Sign and commit with blockchain signatures
• 📊 Audit Trail: Forever immutable on-chain audit logs with IPFS pinning
• 🌐 Public Verification: Anyone can verify capsule integrity via on-chain logs

Project Structure

tala-api/
├── backend/          # Go API server
│   ├── main.go
│   ├── models/       # Database models
│   ├── handlers/     # API endpoint handlers
│   ├── middleware/   # Auth & CORS middleware
│   ├── utils/        # Utilities (crypto, JWT)
│   └── go.mod
└── frontend/         # Next.js web interface
    ├── src/
    │   ├── app/      # Pages (Home, Dashboard, Login, etc)
    │   ├── components/# Reusable components
    │   └── lib/      # Utilities & API client
    └── package.json

Backend Setup

Prerequisites

• Go 1.21 or higher
• SQLite (included with Go)

Installation

cd backend

# Install dependencies
go mod download

# Copy environment variables
cp .env.example .env

# Run the server
go run main.go

The API will be available at http://localhost:8080

Environment Variables (.env)

PORT=8080
DB_PATH=tala.db
JWT_SECRET=your-secret-key-change-in-production

Frontend Setup

Prerequisites

• Node.js 18+ and npm

Installation

cd frontend

# Install dependencies
npm install

# Copy environment variables
cp .env.example .env.local

# Run development server
npm run dev

The frontend will be available at http://localhost:3000

Environment Variables (.env.local)

NEXT_PUBLIC_API_URL=http://localhost:8080/api/v1

API Endpoints

Authentication

• POST /api/v1/auth/register - Create account
• POST /api/v1/auth/login - Login with email/password
• POST /api/v1/auth/login-wallet - Login with wallet

Capsules (Protected)

• POST /api/v1/capsules - Create new capsule
• GET /api/v1/capsules - List user's capsules
• GET /api/v1/capsules/:id - Get capsule details
• PUT /api/v1/capsules/:id - Update capsule
• DELETE /api/v1/capsules/:id - Delete capsule

Signing & Unlocking (Protected)

• POST /api/v1/capsules/:id/sign - Sign & commit capsule
• GET /api/v1/capsules/:id/unlock - Check unlock time eligibility
• POST /api/v1/capsules/:id/unlock - Unlock capsule

Audit Trail

• GET /api/v1/capsules/:id/audit - Get audit trail for capsule
• GET /api/v1/audit - Get all audit trails (protected)

Dashboard

• GET /api/v1/dashboard/stats - Get user stats (protected)
• GET /api/v1/public/stats - Get public stats

Frontend Pages

• / - Landing page
• /login - Login page
• /register - Registration page
• /dashboard - User dashboard with capsules list
• /create-capsule - Create new capsule
• /capsule/:id - Capsule details with timeline and audit trail

Database Schema

Users

• id (UUID)
• email (unique)
• wallet_addr (unique, optional)
• password_hash
• created_at, updated_at

Capsules

• id (UUID)
• user_id (FK)
• title, description
• file_hash, encryption_type
• status (CREATED, SIGNED, UNLOCKED)
• unlock_time, is_locked
• created_at, updated_at

Signatures

• id (UUID)
• capsule_id (FK)
• signed_by (user)
• signature, checksum
• ipfs_hash
• signed_at, created_at

Audit Trails

• id (UUID)
• capsule_id (FK)
• action (CREATE, SIGN, UNLOCK, VERIFY)
• actor (user)
• details, ipfs_hash
• timestamp, created_at

Security Features

1. Authentication: JWT-based token authentication
2. Authorization: User-specific access to capsules
3. Encryption: AES-256-GCM for file encryption
4. Hashing: SHA-256 for data integrity
5. CORS: Configured for cross-origin requests

Deployed URLs

• API: Will be deployed to production
• Frontend: Will be deployed to production

Next Steps

1. Add Ethereum wallet integration (MetaMask)
2. Implement IPFS pinning service
3. Add on-chain verification via smart contracts
4. Implement file upload to IPFS
5. Add email notifications for unlock events
6. Performance optimizations and caching
7. Admin dashboard for statistics

License

MIT License - feel free to use in your projects

Support

For issues or questions, please open an issue on GitHub.