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Overview

Cal.com is a scheduling and appointment management system integrated into the Mondo MOPS ecosystem. It provides a robust solution for managing appointments, scheduling meetings, and coordinating availability across team members. In the MOPS platform, Cal.com serves as the central scheduling infrastructure, accessible via its own subdomain.

Cal.com was formerly known as Calendly and provides similar functionality with additional features for self-hosting and customization.

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Architecture

Cal.com in the MOPS stack consists of:

  • Cal.com Application Container: The main application serving the web interface
  • PostgreSQL Database: Stores all scheduling data, accounts, and configuration
  • Traefik Integration: Handles routing and TLS termination

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Deployment Configuration

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Docker Compose Setup

services:
  database:
    container_name: calcom-db
    image: postgres:17.4
    restart: unless-stopped
    volumes:
      - ./db:/var/lib/postgresql/data/
    environment:
      POSTGRES_USER: ${POSTGRES_USER}
      POSTGRES_PASSWORD: ${POSTGRES_PASSWORD}
      POSTGRES_DB: ${POSTGRES_DB}
    env_file: .env
    networks:
      - calcom-net
    healthcheck:
      test: ['CMD-SHELL', 'pg_isready -U ${POSTGRES_USER}']
      interval: 5s
      timeout: 5s
      retries: 5

  calcom:
    image: calcom/cal.com:v5.0.19
    container_name: calcom-app
    restart: unless-stopped
    volumes:
      - ./data:/app/data
    networks:
      - traefik-net
      - calcom-net
    ports:
      - 3000:3000
    env_file: .env
    environment:
      # Database Configuration
      - DATABASE_URL=postgresql://${POSTGRES_USER}:${POSTGRES_PASSWORD}@calcom-db:5432/${POSTGRES_DB}?sslmode=disable
      - DATABASE_DIRECT_URL=postgresql://${POSTGRES_USER}:${POSTGRES_PASSWORD}@calcom-db:5432/${POSTGRES_DB}?sslmode=disable
      # Google Calendar Integration
      - GOOGLE_API_CREDENTIALS=${GOOGLE_API_CREDENTIALS}
      # SAML Configuration
      - SAML_DATABASE_URL=${SAML_DATABASE_URL}
      - SAML_ADMINS=${SAML_ADMINS}
      # Security and Auth
      - NEXTAUTH_SECRET=${NEXTAUTH_SECRET}
      - CALENDSO_ENCRYPTION_KEY=${CALENDSO_ENCRYPTION_KEY}
      - NEXTAUTH_URL=https://cal.trymondo.com
      # Application URLs
      - NEXT_PUBLIC_WEBAPP_URL=https://cal.trymondo.com
      - NEXT_PUBLIC_APP_URL=https://cal.trymondo.com
      - NEXT_PUBLIC_API_V2_URL=https://cal.trymondo.com/api/v2
      - WEBAPP_URL=https://cal.trymondo.com
      - APP_URL=https://cal.trymondo.com
      # Hostname Configuration
      - ALLOWED_HOSTNAMES="cal.trymondo.com,trymondo.com,localhost:3000"
      # Email Configuration
      - EMAIL_FROM=info@trymondo.com
      - MAIL_FROM=info@trymondo.com
      # SMTP Configuration
      - SMTP_HOST=smtp.mailersend.net
      - SMTP_PORT=587
      - SMTP_USERNAME=${SMTP_USERNAME}
      - SMTP_PASSWORD=${SMTP_PASSWORD}
      - SMTP_SECURE=false
      - SMTP_AUTH_TYPE=LOGIN
      - SMTP_IGNORE_TLS=false
      # Nodemailer Configuration
      - EMAIL_SERVER_HOST=${SMTP_HOST}
      - EMAIL_SERVER_PORT=587
      - EMAIL_SERVER_USER=${EMAIL_SERVER_USER}
      - EMAIL_SERVER_PASSWORD=${EMAIL_SERVER_PASSWORD}
      # Force SMTP over sendmail
      - EMAIL_TRANSPORT=smtp
      - SENDMAIL_DISABLED=true
      - MAILER_PROVIDER=smtp
      # Debug
      - DEBUG=email:*,nodemailer:*,prisma:*
      - EMAIL_DEBUG=true
      - NODE_TLS_REJECT_UNAUTHORIZED=0
      # Application Settings
      - NEXT_PUBLIC_LICENSE_CONSENT=true
      - CALCOM_TELEMETRY_DISABLED=1
      - NEXT_PUBLIC_IS_E2E=0
      - NEXT_PUBLIC_IS_PREMIUM=true
      - NEXT_PUBLIC_TEAM_IMPERSONATION=false
      - NEXT_DISABLE_IMPERSONATION_PAGE=true
    depends_on:
      - database
    labels:
      - 'traefik.enable=true'
      - 'traefik.http.routers.cal.rule=Host(`cal.trymondo.com`)'
      - 'traefik.http.routers.cal.entrypoints=websecure'
      - 'traefik.http.routers.cal.tls=true'
      - 'traefik.http.routers.cal.tls.certresolver=production'
      - 'traefik.http.services.cal.loadbalancer.server.scheme=http'
      - 'traefik.http.services.cal.loadbalancer.server.port=3000'
      - 'traefik.http.routers.cal.middlewares=cors@file,secureHeaders@file'

networks:
  traefik-net:
    external: true
  calcom-net:
    external: true

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Configuration

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Environment Variables

Create a .env file in the Cal.com directory with the following variables:

# Database Configuration
POSTGRES_USER=your_db_username
POSTGRES_PASSWORD=your_db_password
POSTGRES_DB=calcom

# Security Keys
NEXTAUTH_SECRET=your_random_secret_string
CALENDSO_ENCRYPTION_KEY=your_32_character_key

# Google Calendar (Optional)
GOOGLE_API_CREDENTIALS={"web":{"client_id":"your_client_id","project_id":"your_project_id","auth_uri":"https://accounts.google.com/o/oauth2/auth","token_uri":"https://oauth2.googleapis.com/token","auth_provider_x509_cert_url":"https://www.googleapis.com/oauth2/v1/certs","client_secret":"your_client_secret","redirect_uris":["https://cal.trymondo.com/api/auth/callback/google"],"javascript_origins":["https://cal.trymondo.com"]}}

# SAML Configuration (Optional)
SAML_DATABASE_URL=postgresql://${POSTGRES_USER}:${POSTGRES_PASSWORD}@calcom-db:5432/${POSTGRES_DB}?sslmode=disable
SAML_ADMINS=admin@your-domain.com

# SMTP Configuration
SMTP_USERNAME=your_smtp_username
SMTP_PASSWORD=your_smtp_password
EMAIL_SERVER_USER=your_email_username
EMAIL_SERVER_PASSWORD=your_email_password

Store these credentials securely. The .env file contains sensitive information that should not be committed to version control.

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Key Configuration Options

SettingDescriptionExample
ALLOWED_HOSTNAMESComma-separated list of valid hostnamescal.trymondo.com,trymondo.com
NEXTAUTH_URLURL for authenticationhttps://cal.trymondo.com
NEXT_PUBLIC_WEBAPP_URLPublic-facing URLhttps://cal.trymondo.com
SMTP_*Email configurationSettings for your SMTP provider
CALCOM_TELEMETRY_DISABLEDDisable usage tracking1
EMAIL_DEBUGEnable email debuggingtrue for troubleshooting

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Installation and Setup

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Prerequisites

  • Docker and Docker Compose installed
  • External traefik-net network created
  • Domain with DNS pointing to your server
  • SMTP credentials for email notifications

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Deployment Steps

  1. Create Required Networks:

    docker network create calcom-net
# Ensure traefik-net exists
docker network ls | grep traefik-net || docker network create traefik-net

  2. Prepare Directory Structure:

    mkdir -p /opt/apps/calcom/{db,data}
cd /opt/apps/calcom

  3. Create Configuration Files:

    # Create docker-compose.yml using the configuration above
nano docker-compose.yml

# Create .env file with required variables
nano .env

  4. Deploy the Stack:

    docker compose up -d

  5. Monitor Initial Startup:

    docker compose logs -f

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First-Time Setup

Once deployed, complete the setup:

  1. Visit https://cal.trymondo.com
  2. Create the admin account
  3. Configure organization settings
  4. Set up event types and availability

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Integration with Other MOPS Services

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Authentication

Cal.com can be integrated with Auth0 or other authentication providers:

  1. Configure the OAuth provider in your authentication service
  2. Add the appropriate callback URLs
  3. Update the Cal.com environment variables with the OAuth credentials

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API Integration

Cal.com exposes an API that can be used by other MOPS services:

# Example API endpoint
https://cal.trymondo.com/api/v2/

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Maintenance

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Backup and Restore

Cal.com data is stored in two locations:

  1. PostgreSQL Database: Use Backrest to back up the database volume
  2. Application Data: The ./data volume contains uploads and other files

Regular backups should include both components:

# Example backup using docker commands
docker exec calcom-db pg_dump -U ${POSTGRES_USER} ${POSTGRES_DB} > calcom_backup_$(date +%Y%m%d).sql

# Example restore
cat calcom_backup_20250415.sql | docker exec -i calcom-db psql -U ${POSTGRES_USER} ${POSTGRES_DB}

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Updates

To update Cal.com:

  1. Update the image tag in docker-compose.yml
  2. Pull the new image: 
    docker compose pull
  3. Apply the update: 
    docker compose up -d
Always create a backup before updating to prevent data loss.

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Troubleshooting

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Common Issues

IssueSolution
Database connection errorsCheck PostgreSQL container health and connection string
Email not sendingVerify SMTP settings and check logs with DEBUG=email:*
White screen after updateCheck application logs for JavaScript errors
Authentication issuesVerify NEXTAUTH_URL and NEXTAUTH_SECRET settings

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Checking Logs

# View application logs
docker logs calcom-app

# View database logs
docker logs calcom-db

# Follow logs in real-time
docker logs -f calcom-app

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Health Checks

# Check database health
docker exec calcom-db pg_isready -U ${POSTGRES_USER}

# Check application health
curl -kI https://cal.trymondo.com

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Performance Tuning

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Resource Allocation

Cal.com performs well with moderate resources:

  • Database: 1 CPU, 1GB RAM
  • Application: 1-2 CPU, 2GB RAM

For high-traffic instances, consider adding resource constraints to docker-compose.yml:

services:
  database:
    deploy:
      resources:
        limits:
          memory: 1G
          cpus: '1'
  calcom:
    deploy:
      resources:
        limits:
          memory: 2G
          cpus: '2'

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Security Considerations

  1. Database Access: Limit access to the PostgreSQL database
  2. SMTP Credentials: Regularly rotate email credentials
  3. API Security: Monitor API usage and restrict access as needed
  4. Traefik Configuration: Ensure proper security headers are applied (already configured)

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References

This documentation provides a comprehensive guide to deploying, configuring, and maintaining Cal.com within the Mondo MOPS ecosystem. For specific customization needs or advanced features, refer to the official Cal.com documentation.