Panda - Event Ticketing with Bonding Curves

An event ticketing platform that uses AMM-style bonding curves for dynamic pricing. Early supporters pay less, with prices increasing as tickets sell.

Architecture

┌─────────────────────────────────────────────────────────┐
│                      Frontend (Next.js)                 │
│  - Event discovery                                      │
│  - Ticket purchase flow                                 │
│  - User profile / ticket collection                     │
│  - Manager dashboard (create events, set curves)        │
│  - QR code display for tickets                          │
└─────────────────────────────────────────────────────────┘
                            │
                            ▼
┌─────────────────────────────────────────────────────────┐
│                    Privy (Auth + Wallet)                │
│  - Email/social login                                   │
│  - Embedded wallet creation                             │
│  - Transaction signing                                  │
└─────────────────────────────────────────────────────────┘
                            │
                            ▼
┌─────────────────────────────────────────────────────────┐
│                  Smart Contracts (Base)                 │
│                                                         │
│  EventFactory.sol                                       │
│  - createEvent(params) → deploys new Event contract     │
│                                                         │
│  Event.sol                                              │
│  - Bonding curve logic (linear & exponential)           │
│  - buyTicket() → calculates price, mints NFT            │
│                                                         │
│  TicketNFT.sol (ERC-721)                                │
│  - Minted on purchase                                   │
│  - On-chain metadata & SVG image generation             │
└─────────────────────────────────────────────────────────┘

Tech Stack

• Frontend: Next.js 14 (App Router), TypeScript, Tailwind CSS
• Auth/Wallet: Privy for authentication and embedded wallets
• Blockchain: Base Sepolia (Ethereum L2) testnet
• Smart Contracts: Solidity 0.8.20, Hardhat
• Contract Interaction: viem + wagmi

Project Structure

panda/
├── contracts/               # Smart contracts (Hardhat)
│   ├── contracts/
│   │   ├── EventFactory.sol # Factory for deploying events
│   │   ├── Event.sol        # Bonding curve + ticket sales
│   │   └── TicketNFT.sol    # ERC-721 ticket NFTs
│   ├── test/                # Contract tests
│   └── scripts/             # Deployment scripts
│
└── frontend/                # Next.js frontend
    └── src/
        ├── app/             # Next.js pages
        │   ├── page.tsx         # Event discovery
        │   ├── event/[address]/ # Event detail + buy
        │   ├── create/          # Create event
        │   ├── profile/         # My tickets
        │   └── ticket/[id]/     # Ticket detail + QR
        ├── components/      # React components
        ├── hooks/           # Custom hooks for contracts
        ├── lib/             # Utils, contracts, config
        └── providers/       # Privy + wagmi providers

Getting Started

Prerequisites

• Node.js 18+
• npm or yarn

Smart Contracts Setup

# Navigate to contracts directory
cd contracts

# Install dependencies
npm install

# Compile contracts
npm run compile

# Run tests
npm run test

# Start local Hardhat node (optional)
npm run node

# Deploy to local network
npm run deploy:local

# Deploy to Base Sepolia (requires .env configuration)
npm run deploy:base-sepolia

Frontend Setup

# Navigate to frontend directory
cd frontend

# Install dependencies
npm install

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

# Edit .env.local with your values:
# - NEXT_PUBLIC_PRIVY_APP_ID (get from https://dashboard.privy.io)
# - NEXT_PUBLIC_FACTORY_ADDRESS (from deployment)
# - NEXT_PUBLIC_TICKET_NFT_ADDRESS (from deployment)

# Start development server
npm run dev

Environment Variables

Contracts (.env)

BASE_SEPOLIA_RPC_URL=https://sepolia.base.org
PRIVATE_KEY=your_private_key_here
BASESCAN_API_KEY=your_basescan_api_key

Frontend (.env.local)

NEXT_PUBLIC_PRIVY_APP_ID=your_privy_app_id
NEXT_PUBLIC_FACTORY_ADDRESS=0x...
NEXT_PUBLIC_TICKET_NFT_ADDRESS=0x...
NEXT_PUBLIC_CHAIN_ID=84532

Bonding Curves

The platform supports two types of bonding curves:

Linear Curve

price = basePrice + (slope × ticketsSold)

Example: Base price 0.01 ETH, slope 0.001 ETH

• Ticket #1: 0.01 ETH
• Ticket #10: 0.019 ETH
• Ticket #100: 0.109 ETH

Exponential Curve

price = basePrice × (1 + rate)^ticketsSold

Example: Base price 0.01 ETH, rate 5%

• Ticket #1: 0.01 ETH
• Ticket #10: 0.0163 ETH
• Ticket #50: 0.1147 ETH

Features

• Dynamic Pricing: Bonding curves reward early buyers
• NFT Tickets: Each ticket is a unique ERC-721 token
• On-Chain Metadata: SVG images generated on-chain
• QR Code Entry: Tickets include QR codes for venue entry
• Multi-Buy: Purchase up to 10 tickets in one transaction
• Memory Collection: Past tickets become collectible memories

Contract Functions

EventFactory

• createEvent(): Deploy a new event with bonding curve
• getAllEvents(): Get all event addresses
• getEventsByManager(): Get events by creator

Event

• buyTicket(): Purchase a ticket at current price
• buyTickets(count): Purchase multiple tickets
• getCurrentPrice(): Get current ticket price
• getPriceAtSupply(supply): Preview price at any supply
• getPriceRange(start, count): Get prices for curve visualization

TicketNFT

• getTicketData(tokenId): Get ticket metadata
• getTicketsByOwner(address): Get all tickets owned by address
• tokenURI(tokenId): Get on-chain metadata with SVG image

Development

# Run contract tests
cd contracts && npm run test

# Build frontend
cd frontend && npm run build

# Lint frontend
cd frontend && npm run lint

Deployment to Base Sepolia

1. Get Base Sepolia ETH from a faucet
2. Configure your .env with private key
3. Run deployment:

   cd contracts
   npm run deploy:base-sepolia

4. Copy contract addresses to frontend .env.local
5. Deploy frontend to Vercel or similar

License

MIT