A pixel art twin-stick shooter in the browser, inspired by Journey of the Prairie King from Stardew Valley.
Built with Next.js 16, Bun, TypeScript (strict mode), and Tailwind CSS 4. All sprites are drawn purely in code — no image assets.
Move with WASD or Arrow Keys. Your cowboy auto-fires in the direction you're moving. Survive waves of bandits, collect power-ups, and climb the leaderboard.
| Power-up | Effect |
|---|---|
| Spread | Fires 3 bullets in a fan pattern |
| Rapidfire | Doubles fire rate |
| Pierce | Bullets pass through enemies |
| Nuke | Instantly kills all enemies on screen |
- Runtime: Bun
- Framework: Next.js 16 (App Router)
- Language: TypeScript 6 (strict mode)
- Styling: Tailwind CSS 4
- Database: SQLite via
better-sqlite3
src/
├── game/ # Pure TypeScript game engine (no React dependency)
│ ├── types.ts # All interfaces: Player, Bullet, Enemy, PowerUp, etc.
│ ├── engine.ts # Main loop, state machine, rendering
│ ├── input.ts # Keyboard manager (WASD + arrows)
│ ├── sprites.ts # Pixel art defined as 2D hex color arrays
│ ├── player.ts # Movement, auto-fire, power-up effects
│ ├── bullet.ts # Creation, movement, pierce support
│ ├── enemy.ts # 3 types (basic/fast/tank), edge spawning, AI
│ ├── collision.ts
│ ├── wave.ts # Progressive difficulty
│ └── powerup.ts # Spawn, collect, apply, update
├── components/ # React UI layer
│ ├── GameCanvas.tsx # Canvas mount, session management
│ ├── Leaderboard.tsx # Top 10 sidebar
│ └── NameInput.tsx # Game over name entry (1-6 chars)
├── lib/ # Server-side
│ ├── db.ts # SQLite schema & queries
│ └── anticheat.ts # HMAC session tokens, replay prevention
└── app/
├── page.tsx # Layout: game + leaderboard
└── api/ # REST endpoints
├── token/route.ts # GET /api/token
└── scores/route.ts # GET & POST /api/scores
Rendering: OffscreenCanvas at native 320x320, scaled 2x to 640x640 with image-rendering: pixelated.
Anti-cheat: Server issues HMAC-signed session tokens at game start. On game over, the client submits the token with the score. The server validates the signature, checks score/wave/duration plausibility, and prevents replay attacks.
# install
bun install
# dev server
bun dev
# lint + test
bun run check
# unit tests only
vitest run
# build
bun run build73 tests across 9 files covering player mechanics, bullet physics, enemy AI, collision detection, wave progression, power-ups, anti-cheat validation, and database operations. Includes E2E game loop simulation.