D4L Backend

Backend API for D4L, a fantasy meme-token betting platform where users create tokens, register fighters, run battles, and place bets.

Overview

This service is built with NestJS, Prisma, PostgreSQL, and EVM smart-contract integrations via ethers.

Core capabilities:

• Wallet-based auth (challenge + signature verification, JWT sessions)
• User management, profile updates, deposits, and withdrawals
• Meme token creation and lifecycle updates
• Fighting arena flow (register fighter, create battle, place bet, end battle, claim rewards)
• History and analytics (PnL, betting history, leaderboards, dashboard)
• Authenticated image upload with static file serving
• Swagger docs at /api/docs

Tech Stack

• NestJS (REST API)
• Prisma + PostgreSQL
• ethers + deployed contracts (supported networks: sepolia, amoy)
• JWT authentication
• Swagger API documentation
• nestjs-pino logging

Getting Started

1) Install dependencies

yarn install

2) Configure environment variables

Copy .env.example to .env and fill all values:

PORT=<your-backend-port>
DATABASE_URL=<your-postgresql-database-url>
NETWORK=<sepolia-or-amoy>
PLATFORM_PRIVATE_KEY=<your-private-key>
RPC_URL=<your-rpc-url>
JWT_SECRET_KEY=<your-jwt-secret-key>
JWT_EXPIRES_IN=<your-jwt-expires-in>
APP_URL=<your-app-url>
FRONTEND_URL=<your-frontend-url>

3) Run database setup

yarn prisma generate
yarn prisma migrate dev

4) Start the API

# development (watch mode)
yarn start:dev

# production
yarn build
yarn start:prod

Server defaults to:

• API base: http://localhost:<PORT>/api
• Swagger docs: http://localhost:<PORT>/api/docs
• Uploaded files: http://localhost:<PORT>/uploads/<filename>

Scripts

• yarn build - Build NestJS app
• yarn start - Start app
• yarn start:dev - Start in watch mode
• yarn start:prod - Run compiled app
• yarn lint - Run ESLint (auto-fix enabled)
• yarn test - Run unit tests
• yarn test:e2e - Run e2e tests
• yarn test:cov - Run test coverage

API Domains

All endpoints are prefixed with /api.

• auth - wallet challenge and signature verification
• users - account, profile, avatar, wallet operations
• tokens - create/list/get/update token state and transactions
• fighting - fighters, battles, bets, rewards
• history - user activity, pnl, leaderboard, dashboard
• file-upload - authenticated image upload

Data Model (Prisma)

Main entities:

• User
• Token
• Fighter
• Battle
• Bet
• UserHistory
• UserPnL
• BettingHistory
• TokenFightingHistory
• UserStatistics

See prisma/schema.prisma for full schema and enums.

Notes

• CORS allows local frontend origins in development and FRONTEND_URL in production.
• Contract addresses are resolved by NETWORK from src/contracts/addresses.
• Uploaded assets are stored under uploads/ and served statically.

License

MIT