tmap

Turn your taste into treasure.

tmap is a social map of food culture where users discover dishes, mint them as onchain stamps, and earn rewards as trends grow. Built as a Farcaster Mini-App on Base.

Live App

• Mini-App: Open in Farcaster. mbc-tau.vercel.app
• Contract: 0xDF8F506c5D8a69bC8f86D427a0bf6e65B2491a68 (Base Sepolia)

How It Works

1. Discover - Find dishes on the map or explore trending dishes and mint tokens
2. Mint - Pay USDC to mint a dish stamp (must be within 200m of the restaurant/geo-restricted)
3. Earn - As more people mint, your stamp value increases via linesr one way bonding curve (users capped at $10)

Note: Require Base USDC on the testnet. Use the "Get $5" Faucet in case you dont have the USDC in the Base Testnet.

Features

• Bonding Curve Pricing: Price = 1 + (supply × 0.125) USDC
• $10 Max Spend: Per user, per dish
• 70% Sell Value: Sell anytime and get 70% of current market value
• 2.5% Referral Rewards: Share dishes and earn 2.5% referral reward on every mint (check the rewards page!)
• 2.5% Holder Rewards: Existing holders earn when others mint (check the holdings fee in the rewards page!)
• Geo-Verification: Must be at the restaurant to create a dish (within 200m)
• Farcaster Integration: Native social sharing and wallet connection and earn token referral fee.

Tech Stack

Layer	Tech
Frontend	Next.js 15, TypeScript, Tailwind CSS
Blockchain	Base Sepolia, Solidity, Hardhat
Token	ERC1155 (OpenZeppelin)
Database	MongoDB Atlas
Auth	Farcaster Mini-App SDK
Wallet	wagmi v2, viem, Farcaster Wallet Connector
Paymaster	Coinbase Paymaster
Maps	Google Maps API

Architecture

Gasless Transactions

All transactions are gasless for users via Coinbase Paymaster integrated through Farcaster's wallet infrastructure. We use wagmi's useSendCalls hook with the farcasterMiniApp connector which automatically routes transactions through Farcaster's sponsored transaction flow.

Bonding Curve Math

Linear bonding curve with arithmetic series pricing:

• Base Price: $1 USDC
• Slope: $0.125 per token
• Price Formula: Price(n) = 0.1 + (n × 0.0125) where n = current supply
• Mint Cost: Uses arithmetic series sum Cost = n/2 × (firstPrice + lastPrice)
• Sell Value: 70% of current market value (one-way curve)

Fee Distribution (5% total on mint)

Fee	Recipient	Purpose
2.5%	Referrer	Incentivize sharing
2.5%	Holder Pool	Time-weighted rewards for existing holders

Reward Calculation

Holder rewards use a time-weighted distribution model:

• rewardPerToken = rewardPerTokenStored + (rewardFee × 1e18 / totalSupply)
• earned = balance × (rewardPerToken - userRewardPerTokenPaid)

Smart Contract

TmapDishes.sol - ERC1155 token with bonding curve mechanics

Contract: 0xDF8F506c5D8a69bC8f86D427a0bf6e65B2491a68
Network: Base Sepolia (Chain ID: 84532)
USDC: 0x036CbD53842c5426634e7929541eC2318f3dCF7e

Contract Functions

Function	Description
createDish(bytes32, string)	Create new dish with metadata
mint(bytes32, uint256, address)	Mint tokens with USDC, optional referrer
sell(bytes32, uint256)	Sell tokens back for 70% value
claimRewards(bytes32)	Claim holder rewards for a dish
claimReferralRewards()	Claim accumulated referral earnings
getCurrentPrice(bytes32)	Get current token price
getTokensForUsdc(bytes32, uint256)	Calculate tokens for USDC amount
getSellValue(bytes32, uint256)	Get sell value for tokens

Security

• OpenZeppelin ReentrancyGuard on all state-changing functions
• Ownable for admin functions
• $10 max spend per user per dish (prevents whale manipulation)
• USDC approval required before minting

Local Development

# Install dependencies
npm install

# Set up environment variables
cp .env.example .env.local
# Add your MONGODB_URI, GOOGLE_MAPS_API_KEY, etc.

# Run development server
npm run dev

Smart Contracts

cd contracts
npm install

# Compile
npx hardhat compile

# Test
npx hardhat test

# Deploy
npx hardhat run scripts/deploy.ts --network baseSepolia

Environment Variables

MONGODB_URI=
NEXT_PUBLIC_GOOGLE_MAPS_API_KEY=
NEXT_PUBLIC_TMAP_DISHES_CONTRACT_ADDRESS=
NEXT_PUBLIC_USDC_CONTRACT_ADDRESS=
NEXT_PUBLIC_APP_URL=
FAUCET_PRIVATE_KEY=

Project Structure

├── app/                    # Next.js app router
│   ├── api/               # API routes
│   ├── components/        # React components
│   ├── dish/[id]/        # Dish detail page
│   ├── create/           # Create dish flow
│   ├── profile/          # User profile
│   ├── rewards/          # Rewards dashboard
│   └── providers/        # Farcaster & Wagmi providers
├── contracts/             # Solidity smart contracts
│   └── contracts/
│       ├── TmapDishes.sol
│       └── libraries/BondingCurve.sol
├── lib/                   # Utilities
│   ├── contracts.ts      # ABIs and addresses
│   ├── mongodb.ts        # Database connection
│   └── geo.ts            # Location utilities
└── public/               # Static assets
    └── .well-known/      # Farcaster manifest

Links

• Base Sepolia Explorer
• Farcaster Mini-Apps Docs