# Quickstart: Deploying to a Custom Host

This guide provides the steps to configure the application to run on a public-facing domain.

## Prerequisites

- A configured hosting environment with Docker and Docker Compose.
- A public domain name pointing to your host.
- (Optional) A reverse proxy (like Nginx or Traefik) to handle HTTPS/SSL termination.

## Configuration Steps

### 1. Backend Configuration

In the `backend/` directory, create a file named `.env`.

Add the following line to this file, replacing the URL with your **frontend's** public domain:

```
CORS_ORIGIN=https://your-frontend-domain.com
```

This tells the backend to accept API requests from your frontend application.

### 2. Frontend Configuration

In the `frontend/` directory, create a file named `.env`.

Add the following line to this file, replacing the URL with your **backend's** public API domain:

```
REACT_APP_API_URL=https://api.your-domain.com
```

This tells the frontend where to send its API requests.

### 3. Docker Compose Configuration

Modify the `docker-compose.yaml` file in the project root to pass these environment variables to the containers.

Update the `backend` and `frontend` services to include the `env_file` property:

```yaml
services:
  backend:
    # ... existing configuration ...
    env_file:
      - ./backend/.env

  frontend:
    # ... existing configuration ...
    env_file:
      - ./frontend/.env
```

### 4. Deployment

With the `.env` files in place and `docker-compose.yaml` updated, you can now build and run the application.

```bash
docker-compose up --build -d
```

The application should now be accessible at your public domain without CORS errors.