Metro And Rail Carriage Optimization System

Which carriage door, for which exit, for which station?

🚇 Try MARCOS Live → • 📖 View Documentation ↓

MARCOS helps you find the best carriage and door position for your metro exit. Don't waste time fighting through the crowds at platforms — know exactly where to stand for the fastest exit.

What is MARCOS?

MARCOS is a simple web application, built on top of a crowdsourced, verified database, that tells you which carriage and door to use when traveling on a metro system, so you can exit at the most convenient point for your destination.

Simply select your metro system, line, departure station, and destination station, and MARCOS will show you the optimal carriage and door positions for each exit at your destination.

How to Contribute

We welcome contributions! The easiest way to help is by adding station data for your local metro system.

Where Data is Stored

All station data is stored in YAML files in the data/systems/ directory:

data/systems/
├── systems.yaml                    # List of all metro systems
├── london_underground/
│   ├── lines.yaml                  # Lines for this system
│   └── stations/
│       └── tottenham_court_road.yaml
└── nyc_subway/
    ├── lines.yaml
    └── stations/
        └── station_name.yaml

Station Data Format {#station-data-format}

Each station is stored as a YAML file following this simple format. Here's the example from Tottenham Court Road:

station_name: Tottenham Court Road
status: dummy

platforms:
  central:
    eastbound:
      door_side: right
      exits:
        northern: 4.2
        oxford_street_east: 1.2
    westbound:

  northern:
    southbound:
      door_side: right
      exits:
        central: 1.3
        street: 6.3
    northbound:
      door_side: right
      exits:
        central:eastbound: 1.3
        street: 6.3

Format Guide

• station_name: The display name of the station (optional)
• status: Set to "dummy" for placeholder/test data (optional)
• platforms: A dictionary where each key is a line ID (must match an ID in lines.yaml)
  • Each line contains directions (e.g., eastbound, westbound, northbound, southbound, uptown, downtown)
  • Each direction can have:
    • door_side: Which side of the train the doors are on (left or right)
    • exits: A dictionary mapping exit names to carriage/door positions

Carriage/Door Format

Values like 4.2 mean:

• 4 = 4th carriage (counting from the front of the train)
• 2 = 2nd door (on that carriage)

So 4.2 means "4th carriage, 2nd door".

Adding a New Station

1. Find the station ID: Use a lowercase, underscore-separated version of the station name

   • Example: "Tottenham Court Road" → tottenham_court_road

2. Create the YAML file:

   • Location: data/systems/[system_id]/stations/[station_id].yaml
   • Example: data/systems/london_underground/stations/tottenham_court_road.yaml

3. Add the basic structure:

   station_name: Your Station Name
   
   platforms:
     line_id:
       direction:
         door_side: right
         exits:

4. Add exits for each direction: For each platform direction, add the exits with their carriage/door positions:

   exits:
     exit_name: 4.2
     another_exit: 1.1

5. Test locally: Run npm run dev and verify your station appears and works correctly

6. Submit a Pull Request: Once you've added your station data, submit a PR to the repository!

Adding Exits to a Station

To add exits to an existing station:

1. Open the station's YAML file in data/systems/[system_id]/stations/[station_id].yaml

2. Find the platform and direction you want to add exits to

3. Add exit entries under the exits: section:

   platforms:
     central:
       eastbound:
         door_side: right
         exits:
           new_exit_name: 3.1 # 3rd carriage, 1st door
           another_exit: 5.2 # 5th carriage, 2nd door

4. Exit names should be lowercase with underscores (e.g., oxford_street_east, main_entrance)

5. Carriage/door format: Always use carriage.door (e.g., 4.2, 1.1, 6.3)

Tips for Collecting Data

• Stand at different positions in the train and note which exit you're closest to
• Count carriages from the front of the train (the first carriage is 1)
• Count doors on each carriage (the first door is 1)
• Note the direction you're traveling (important for platforms on different sides)
• Mark as status: dummy if you're unsure about the accuracy

Example: Complete Station Entry

station_name: Example Station

platforms:
  central:
    eastbound:
      door_side: right
      exits:
        main_entrance: 2.1
        side_exit: 4.2
    westbound:
      door_side: left
      exits:
        main_entrance: 3.1
        side_exit: 5.2

Getting Started (Development)

# Install dependencies
npm install

# Generate data module (reads YAML files)
npm run generate-data

# Start development server
npm run dev

Open http://localhost:3000 to see the app.

Project Structure

• data/systems/ - Metro system data (YAML files)
• app/ - Next.js application
• lib/data.ts - Data access functions (uses generated static data)
• scripts/generate-data.ts - Build script that converts YAML to TypeScript

License

This project is open source. Contributions welcome!