Hotlap Daily

Community driven racing game with new tracks everyday! Check your score live on the leaderboard.

A daily browser racing game. Each day a new procedurally‑generated F1‑style track goes live; players set the fastest lap they can and submit it to a global leaderboard.

Quick start

npm install
npm run dev        # http://localhost:3000

That's it. The game is fully playable, and lap submissions / leaderboards work against an in‑memory database that (optionally) persists to ./.data/.

Commands

npm run dev          # Dev server on :3000
npm run build        # Production build
npm run start        # Run the production build
npm run lint         # ESLint

# Database (only needed if you opt into PostgreSQL)
npm run db:push      # Push the Prisma schema to your DB
npm run db:studio    # Prisma Studio GUI

Persistence: in‑memory by default, Postgres optional

The data layer is pluggable (see src/lib/prisma.ts):

DB_BACKEND	When	Notes
memory	default (no DATABASE_URL)	Zero setup. Persists to ./.data/hotlap-db.json unless DB_PERSIST=false.
postgres	default when DATABASE_URL is set	Prisma + PostgreSQL. Run npm run db:push to create the schema.

Every API route imports a single prisma client; the backend is chosen at runtime, so route code is identical regardless of which store is active.

To use Postgres:

cp env.example .env
# set DATABASE_URL=... in .env
npm run db:push
npm run dev

See env.example for all configuration (admin password, anti‑cheat secret, etc.). No secrets are required to run locally.

How it plays

• A track is selected per UTC day. The client can generate tracks entirely on its own (see public/game/tracks/), so the game works even with an empty database — it falls back to a built‑in track.
• Complete a clean lap; an anti‑cheat layer validates it client‑side, then the server re‑validates (proof‑of‑work + HMAC + physics constants) before the time is accepted.
• Times feed a global leaderboard and per‑track leaderboards. You can race against a "ghost" replay of a previous fast lap.

Project layout

src/                      Next.js app (server shell + API routes)
  app/                    Pages and /api routes
  lib/                    Server libraries
    prisma.ts             Pluggable data client (memory | postgres)
    db/memoryClient.ts    Zero‑setup in‑memory backend
    trackGenerator.ts     Procedural track generation (track generator page)
    trackValidator.ts     Server‑side track/lap validation
public/game/              Client‑side game engine (static ES modules)
  engine.js               The Game orchestrator + game loop
  physics/                Car physics + input controller
  render/                 Canvas drawing + colors
  anticheat/              Client‑side checkpoint/line‑crossing validation
  net/                    API client + telemetry
  tracks/                 Track generator functions
  ui/                     HUD, leaderboard, share card
  util/                   Pure helpers (geometry)
prisma/                   Prisma schema (PostgreSQL)

See ARCHITECTURE.md for the full design, data flow, and anti‑cheat details.

License

Released under the MIT License.