RainLoop Technology Intelligence

What is RainLoop?

RainLoop is a modern, lightweight webmail client written in PHP and JavaScript. Designed as a simple, fast alternative to heavier solutions, RainLoop provides a clean, intuitive interface for accessing email through IMAP servers. It's available in both Community (free) and Standard (paid) editions.

The client features a responsive design that works across desktop and mobile browsers without separate applications. Its minimalist approach focuses on core email functionality—reading, composing, and organizing messages—without the complexity of calendar or task management.

RainLoop supports multiple email accounts, allowing users to access Gmail, Outlook.com, Yahoo, and custom IMAP servers from a single interface. It includes OpenPGP encryption support for secure communication and offers easy installation with minimal configuration required.

RainLoop Features

Multiple Accounts: Unified inbox optional. Quick account switching. Gmail integration. Custom domains. OAuth support.

Modern Interface: Clean, responsive design. Keyboard shortcuts. Drag and drop. Conversation threading. Preview pane.

Compose: Rich text editor. Inline images. File attachments. Drafts. Template signatures.

Security: OpenPGP encryption. S/MIME support. Two-factor authentication. HTTPS enforcement. Secure sessions.

Search: Server-side IMAP search. Quick filters. Folder search. Contact search. Message search.

Administration: Web-based admin panel. Domain management. User settings. Plugin management. Security settings.

RainLoop Use Cases

Personal Email: Self-hosted webmail. Multi-account access. Privacy-focused email. Home server email.

Small Business: Company webmail. Simple email access. No complex requirements. Cost-effective solution.

Web Hosting: Hosting panel integration. Customer email access. cPanel alternative. Lightweight hosting webmail.

NAS Integration: Synology packages. QNAP integration. Home NAS email. Self-contained email.

Container Deployments: Docker installations. Kubernetes pods. Microservices architecture. Cloud deployments.

Privacy-Conscious: Self-hosted email. No third-party access. Data ownership. Encrypted communications.

RainLoop Code Examples

Docker Deployment

# docker-compose.yml
version: '3'
services:
  rainloop:
    image: hardware/rainloop
    container_name: rainloop
    volumes:
      - ./data:/rainloop/data
    ports:
      - "8888:8888"
    environment:
      - LOG_TO_STDOUT=true
      - MEMORY_LIMIT=128M
      - UPLOAD_MAX_SIZE=25M

Nginx Configuration

# RainLoop Nginx config
server {
    listen 443 ssl http2;
    server_name mail.example.com;

    root /var/www/rainloop;
    index index.php;

    # Deny access to sensitive directories
    location ^~ /data {
        deny all;
    }

    location ~ \.php$ {
        fastcgi_pass unix:/var/run/php-fpm.sock;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
        include fastcgi_params;
    }

    # Admin panel access
    location /admin {
        # Restrict admin access
        allow 192.168.1.0/24;
        deny all;
    }
}

Domain Configuration

# data/_data_/_default_/domains/example.com.ini
imap_host = "mail.example.com"
imap_port = 993
imap_secure = "SSL"
smtp_host = "mail.example.com"
smtp_port = 587
smtp_secure = "TLS"
smtp_auth = On

RainLoop Benefits

Lightweight: Fast performance. Minimal resources. Quick loading. Efficient operation.

Easy Install: Unzip and run. Web-based setup. No database required. Minimal configuration.

Modern Design: Clean interface. Mobile responsive. Intuitive navigation. Contemporary look.

Multi-Account: Multiple email providers. Unified access. Quick switching. Centralized management.

Security: OpenPGP built-in. Secure connections. 2FA support. Privacy focused.

Plugin System: Extend functionality. Theme customization. Integration options. Community plugins.