🐟 Salmon.cafe - Global Salmon Simulator

A multiplayer neglect simulator where one salmon is shared by all users. Keep it alive by feeding it, but be careful - overfeeding or neglect will cause death!

Features

• Global Shared Salmon: One fish shared by everyone on the server
• Hunger System: Hunger decays by 5 points per hour (0-100 scale)
• Death Mechanics:
  • Dies from starvation (hunger ≤ 0)
  • Dies from overfeeding (hunger ≥ 100)
• Tank Levels: Unlock better tanks based on survival days
  • Tank 1: 0 days
  • Tank 2: 2 days
  • Tank 3: 5 days
  • Tank 4: 10 days
  • Tank 5: 20 days
• Nightly Deliveries: Automatic food delivery at 3 AM
• Death History: Track all deaths with timestamp, cause, and duration
• Action Logging: Records all feed/order actions
• Prometheus Metrics: /metrics endpoint for monitoring
• Simple HTML UI: Real-time updates showing hunger, tank, status, and controls

Tech Stack

• Node.js v20+ with ES modules
• Express.js - Web server
• Drizzle ORM - Database management
• Better-SQLite3 - SQLite database
• Prom-Client - Prometheus metrics

Installation

npm install

Usage

Start the server

npm start

Or for development with auto-reload:

npm run dev

The server will start on port 3000 (or PORT environment variable):

• UI: http://localhost:3000
• Metrics: http://localhost:3000/metrics
• Health: http://localhost:3000/health

API Endpoints

GET /api/status

Get current salmon state

{
  "isAlive": true,
  "hunger": 50,
  "tankLevel": 1,
  "daysSurvived": 0,
  "bornAt": "2026-01-12T05:32:34.000Z",
  "lastFedAt": null
}

POST /api/feed

Feed the salmon (+15 hunger)

{
  "success": true,
  "message": "Fed the salmon",
  "hunger": 65
}

POST /api/order

Order food for the salmon (+25 hunger)

{
  "success": true,
  "message": "Ordered food for the salmon",
  "hunger": 75
}

POST /api/respawn

Respawn a new salmon after death

{
  "success": true,
  "message": "New salmon spawned!"
}

GET /api/history?limit=10

Get death history

[
  {
    "id": 1,
    "diedAt": "2026-01-12T05:33:31.000Z",
    "cause": "overfeeding",
    "daysSurvived": 0,
    "durationHours": 0.016,
    "finalHunger": 100,
    "tankLevel": 1
  }
]

GET /api/actions?limit=20

Get recent actions

[
  {
    "id": 1,
    "action": "feed",
    "timestamp": "2026-01-12T05:32:52.000Z",
    "hungerBefore": 50,
    "hungerAfter": 65
  }
]

GET /metrics

Prometheus metrics endpoint

# HELP salmon_alive Whether the salmon is alive (1) or dead (0)
# TYPE salmon_alive gauge
salmon_alive 1

# HELP salmon_hunger Current hunger level of the salmon (0-100)
# TYPE salmon_hunger gauge
salmon_hunger 50

# HELP salmon_tank_level Current tank level (1-5)
# TYPE salmon_tank_level gauge
salmon_tank_level 1
...

Game Mechanics

Hunger Decay

• Hunger decreases by 5 points per hour
• Updates automatically every minute
• Range: 0-100

Feeding

• Feed: Increases hunger by 15
• Order: Increases hunger by 25 (bigger meal)

Death Conditions

• Starvation: Hunger drops to 0 or below
• Overfeeding: Hunger reaches 100

Tank Upgrades

Tanks unlock automatically based on days survived:

• Days 0-1: Tank 1
• Days 2-4: Tank 2
• Days 5-9: Tank 3
• Days 10-19: Tank 4
• Days 20+: Tank 5

Nightly Delivery

At 3 AM daily, the salmon receives automatic food delivery (+20 hunger) if alive.

Project Structure

salmon.cafe/
├── src/
│   ├── db/
│   │   ├── schema.js        # Database schema definitions
│   │   └── index.js         # Database connection and initialization
│   ├── services/
│   │   ├── simulator.js     # Core salmon simulator logic
│   │   └── metrics.js       # Prometheus metrics
│   ├── public/
│   │   └── index.html       # HTML UI
│   └── index.js             # Express server entry point
├── data/
│   └── salmon.db            # SQLite database (auto-created)
├── package.json
└── drizzle.config.js        # Drizzle ORM configuration

Development

The project uses:

• ES6+ modules (type: "module" in package.json)
• Node.js v20+ features
• SQLite with WAL mode for better concurrency
• Auto-updating hunger system (runs every minute)

Database

The SQLite database stores:

• salmon_state: Current salmon state (single row)
• death_history: All historical deaths
• action_log: All user actions (feed/order)

Database file is automatically created at ./data/salmon.db on first run.

Monitoring

Prometheus metrics are available at /metrics for monitoring:

• salmon_alive: Alive status (1/0)
• salmon_hunger: Current hunger level
• salmon_tank_level: Current tank level
• salmon_days_survived: Days the current salmon has survived
• salmon_total_deaths: Total number of deaths
• salmon_total_actions: Total user actions

License

MIT