Privacy Tools Guide

The Email Privacy Problem

Gmail reads your emails to serve ads. ProtonMail is closed-source. Mailbox.org (privacy-focused) is owned by T-Online (German mega-corp). The only way to guarantee privacy: self-host.

But self-hosting email is hard:

This guide covers five self-hosted email platforms and helps you choose based on time/money trade-offs.

The Self-Hosted Email Landscape

Solution Setup Time Monthly Cost Maintenance Spam Fighting
Mail-in-a-Box 30 min $5-20 Low Built-in (decent)
Mailcow 45 min $8-25 Low Excellent (sieve scripts)
iRedMail 60 min $5-30 Medium Good (SpamAssassin)
Modoboa 60 min $10-30 Medium Good (Rspamd)
Docker Mailserver 90 min $5-25 High Configurable

Mail-in-a-Box: Easiest Setup

Mail-in-a-Box is purpose-built for privacy advocates who don’t want to spend 10 hours configuring email.

What’s Included

- Postfix (SMTP server)
- Dovecot (IMAP/POP3)
- Roundcube (webmail)
- Fail2ban (brute-force protection)
- Spam filtering (basic)
- SSL certificates (auto-renewed)
- Backup system (daily to B2/S3)

Installation

# Step 1: Rent a VPS
# Recommended: Linode, DigitalOcean, Hetzner
# Specs: 2GB RAM, 2 CPU, 40GB SSD
# Cost: $10-20/month

# Step 2: Install Mail-in-a-Box
curl https://mailinabox.email/setup.sh | sudo bash

# Step 3: Access admin panel
# https://your-domain.com/admin
# Login with password set during install

# Step 4: Add email addresses
# Admin panel > Mail > Add email address

Pricing Breakdown

VPS (Linode 2GB):           $12/month
Domain registration:         $12/year ($1/month)
B2 backup storage:           $6/month (10GB/month)
Total:                       $19/month

For 5 email addresses: $3.80 per address
vs. ProtonMail: $5/month for 1 address

Key Features

Webmail (Roundcube):

Access via: https://mail.your-domain.com
Web-based email client
Works on mobile browsers
No app installation needed
Can't match native Mail.app performance (acceptable)

Spam Filtering:

Mail-in-a-Box uses:
- SPF/DKIM/DMARC (prevent impersonation)
- SpamAssassin (basic ML filtering)
- Greylisting (delays unknown senders)

Result: ~85% spam caught automatically
Note: NOT as aggressive as Gmail/Proton (more false negatives)

Backup System:

Built-in backup to:
- AWS S3
- Backblaze B2
- Or SFTP server

Frequency: Daily
Retention: 30 days (configurable)
Recovery: Full mailbox or single email

Configuration Example: Custom Domain

# Step 1: Add domain in admin panel
# Admin > Mail > Add domain

# Step 2: Update DNS records (provided by panel)
# MX record: mail.your-domain.com
# SPF record: v=spf1 include:mail.your-domain.com ~all
# DKIM record: [public key from admin panel]
# DMARC record: v=DMARC1; p=quarantine;

# Step 3: Wait 24 hours for DNS propagation
# Step 4: Create email address
# Admin > Mail > Add mail user
# user@your-domain.com

# Step 5: Receive email in Roundcube webmail

Strengths

Weaknesses

Best For

Maintenance Schedule

# Monthly: Check admin panel for updates
# Mail-in-a-Box > System > Check for updates > Install

# Weekly: Monitor disk space
# Admin > Backup status > Ensure backup succeeds

# Quarterly: Review spam training
# Manually mark false positives/negatives
# (Helps SpamAssassin learn over time)

Mailcow: Best Spam Filtering

Mailcow is a dockerized email stack with excellent spam filtering through Sieve scripts.

What’s Included

- Postfix (SMTP)
- Dovecot (IMAP/POP3)
- Nginx (reverse proxy)
- SOGo (webmail + calendar + contacts)
- Rspamd (advanced spam filtering)
- Sieve (email filtering rules)
- Two-factor auth (built-in)
- LDAP support (for multiple users)

Installation

# Step 1: Rent a VPS (same as Mail-in-a-Box)
# Linode 2GB: $12/month

# Step 2: Install Docker
curl -fsSL https://get.docker.com | sh

# Step 3: Clone Mailcow
cd /opt
git clone https://github.com/mailcow/mailcow-dockerized.git
cd mailcow-dockerized

# Step 4: Configure
./generate_config.sh
# Follow prompts for domain, hostname, IP

# Step 5: Start containers
docker-compose up -d

# Step 6: Access admin panel
# https://your-domain.com/admin
# Login with admin credentials

Pricing

VPS (Linode 2GB):           $12/month
Domain registration:         $12/year ($1/month)
B2 backup storage:           $6/month
Total:                       $19/month

Same cost as Mail-in-a-Box, better features.

Key Feature: Advanced Spam Filtering

Rspamd Configuration:

Mailcow uses Rspamd with pre-trained models:
- Neural networks (learns from data)
- Bayes filtering (learns what's spam)
- Image classification (detects spam images)
- URL reputation (checks URLs against blocklists)
- SPF/DKIM/DMARC validation

Result: ~92% spam caught automatically

Sieve Scripts (Custom Filtering):

Sieve is a mail filtering language (RFC 5228)
Create rules like:
if header :contains "Subject" "urgent" {
  fileinto "INBOX.Urgent";
}

if anyof (
  header :contains "From" "boss@work.com",
  header :contains "From" "cto@company.com"
) {
  fileinto "INBOX.Work";
}

Effect: Auto-organize email by custom rules

Webmail (SOGo):

Better than Roundcube:
- Integrated contacts
- Integrated calendar
- Better UI (modern)
- Smartphone support
- WebDAV/CalDAV support
- Task management

Configuration Example: Spam Training

# Step 1: Mark emails as spam
# SOGo > Email > Select spam message > Mark as Spam

# Step 2: Rspamd learns from patterns
# Over 1-2 weeks, spam filtering improves

# Step 3: Adjust Rspamd thresholds (advanced)
# Admin panel > Settings > Rspamd
# Adjust scores for stricter filtering

# Step 4: Fine-tune with Sieve rules
# Admin > User > Settings > Filters
# Create custom rules

Strengths

Weaknesses

Best For

Maintenance Schedule

# Weekly: Monitor container health
# docker-compose logs | grep error

# Monthly: Update containers
# cd /opt/mailcow-dockerized
# git pull
# docker-compose pull
# docker-compose up -d

# Quarterly: Review spam scores
# Admin > Rspamd > Monitor spam trends
# Adjust thresholds if needed

iRedMail: Traditional, Stable

iRedMail uses traditional Linux packages (not containerized). It’s the old-school approach but stable.

What’s Included

- Postfix (SMTP)
- Dovecot (IMAP/POP3)
- Apache/Nginx (web server)
- Roundcube (webmail)
- SpamAssassin (spam filtering)
- Fail2ban (brute-force protection)
- OpenLDAP (user directory)
- MySQL (database)

Installation

# Step 1: Download iRedMail
cd /root
wget https://github.com/iredmail/iRedMail/releases/download/...

# Step 2: Extract and run installer
tar xjf iRedMail-x.x.x.tar.bz2
cd iRedMail-x.x.x
bash iRedMail.sh

# Step 3: Follow prompts
# Choose web server (Apache/Nginx)
# Set domain name
# Set admin password
# Choose components to install

# Step 4: Reboot server
# Installer modifies system files

Pricing

VPS (Linode 2GB):           $12/month
Domain:                      $1/month
Backup storage:              $6/month
Total:                       $19/month

Key Features

Traditional Architecture:

iRedMail installs everything on OS:
- Postfix via package manager
- Dovecot via package manager
- MySQL via package manager
- OpenLDAP via package manager

Pros:
- Standard Linux tools apply
- Easy to troubleshoot (no Docker abstractions)
- Uses OS security updates

Cons:
- System-level changes
- Package conflicts possible
- Harder to migrate

Spam Filtering:

SpamAssassin + Bayes:
- Traditional ML approach
- Configurable rules
- Slow to adapt (needs retraining)

Result: ~80% spam blocked
Less effective than Rspamd

Webmail (Roundcube):

Same as Mail-in-a-Box
Functional but dated UI
Works fine for email reading/writing

Configuration Example: Custom Rules

# iRedMail stores config in /etc/postfix
# Sieve rules go in Dovecot config

# Create filter for specific sender:
# In Roundcube: Settings > Filters > Add
# Rule: If from contains "newsletter@sender.com"
# Action: Move to folder "Newsletters"

# Apply server-side (persistent across clients)

Strengths

Weaknesses

Best For

Modoboa: Modern and Flexible

Modoboa is a newer project (started 2013) with modern architecture and excellent customization.

What’s Included

- Postfix (SMTP)
- Dovecot (IMAP/POP3)
- Nginx (reverse proxy)
- Django web framework (webmail)
- Rspamd (spam filtering)
- MongoDB/MySQL (database)
- Ansible playbooks (deployment)

Installation

# Step 1: Download Modoboa installer
git clone https://github.com/modoboa/modoboa-installer.git

# Step 2: Configure installer
cd modoboa-installer
# Edit inventory file with domain/hostname/IP

# Step 3: Run Ansible
ansible-playbook -i inventory playbook.yml

# Step 4: Access admin panel
# https://admin.your-domain.com
# Login with credentials

Pricing

VPS (Linode 2GB):           $12/month
Domain:                      $1/month
Backup:                      $6/month
Total:                       $19/month

Key Features

Modern Architecture:

Built on Django (Python web framework)
Advantages:
- Easy to extend (Python plugins)
- Good API (REST, GraphQL)
- Modern UI (responsive design)
- Good for future customization

Example custom plugin:
# Create /modoboa/plugins/custom_plugin/
# Implement email forwarding rule
# Integrate with external service

Webmail (Django-based):

Modern UI:
- Responsive design (works on mobile)
- Better UX than Roundcube
- Customizable
- Supports multiple themes
- Good search functionality

Admin Interface:

Modoboa admin is more powerful:
- Manage multiple domains
- Per-user quotas
- Resource monitoring
- Per-domain spam rules
- Easy API access

Configuration Example: Multiple Domains

# Step 1: Add domain in admin panel
# Admin > Domains > Add domain
# my-company.com

# Step 2: Configure DNS
# MX record: mail.my-company.com
# SPF/DKIM/DMARC records (provided by panel)

# Step 3: Create users
# Admin > Users > Add user
# alice@my-company.com
# bob@my-company.com

# Step 4: Set mailbox quotas
# Admin > Users > alice@my-company.com > Quota: 5GB

# Step 5: Enable forwarding (advanced)
# Admin > Aliases > Add alias
# forward-all@my-company.com → alice, bob

Strengths

Weaknesses

Best For

Docker Mailserver: Maximum Control

Docker Mailserver is a fully customizable Docker setup. Everything is configurable; nothing is pre-configured.

What’s Included

- Postfix (SMTP)
- Dovecot (IMAP/POP3)
- Rspamd (spam filtering)
- ClamAV (virus scanning)
- Let's Encrypt (SSL)
- Docker Compose configuration

Installation

# Step 1: Clone repository
git clone https://github.com/docker-mailserver/docker-mailserver

# Step 2: Create docker-compose.yml
cd docker-mailserver
cp docker-compose.yml.example docker-compose.yml

# Step 3: Generate environment file
cp .env.example .env

# Step 4: Configure mailbox accounts
./setup.sh email add user@example.com password123
./setup.sh email add admin@example.com password456

# Step 5: Start containers
docker-compose up -d

# Step 6: Access webmail (optional)
# Install Roundcube separately
docker run -d -p 80:80 roundcube

Pricing

VPS (Linode 2GB):           $12/month
Domain:                      $1/month
Backup:                      $6/month
Total:                       $19/month
(Same as others, more work)

Key Features

Full Customization:

Every component configurable via environment:
- Postfix settings
- Dovecot settings
- Rspamd thresholds
- Virus scanning (on/off)
- Greylisting (on/off)

Example:
# .env file
POSTFIX_LOG_LEVEL=1
RSPAMD_DCC=1
ENABLE_CLAMAV=1
ENABLE_FAIL2BAN=1

CLI Management:

./setup.sh provides:
- Email account creation/deletion
- Password changes
- Quota management
- Alias management
- Domain setup

Example:
./setup.sh email add work@mydomain.com mypassword
./setup.sh email restrict add work@mydomain.com spam
./setup.sh mailbox quota set work@mydomain.com 5GB

No Webmail Included:

You must add your own:
- Roundcube (popular)
- SOGo (better)
- Custom web app

Advantages:
- Choose what webmail suits you
- Not locked to one UI

Disadvantages:
- Extra configuration
- Extra Docker container

Configuration Example: Advanced Setup

# docker-compose.yml

version: '3.3'
services:
  mailserver:
    image: docker-mailserver/docker-mailserver:latest
    ports:
      - "25:25"
      - "143:143"
      - "465:465"
      - "587:587"
      - "993:993"
    environment:
      DOMAIN: "my-domain.com"
      POSTMASTER_ADDRESS: "admin@my-domain.com"
      ENABLE_CLAMAV: 1          # Virus scanning
      ENABLE_FAIL2BAN: 1         # Brute-force protection
      ENABLE_SPAMASSASSIN: 1     # Spam filtering
      RSPAMD_DCC: 1              # DCC checks
      ENABLE_MANAGESIEVE: 1      # Sieve filtering
    volumes:
      - maildata:/var/mail
      - mailstate:/var/mail-state
      - maillogs:/var/log/mail
    restart: always

  roundcube:
    image: roundcube/roundcubemail:latest
    ports:
      - "8080:80"
    environment:
      ROUNDCUBE_DEFAULT_HOST: mailserver
      ROUNDCUBE_SMTP_SERVER: mailserver

volumes:
  maildata:
  mailstate:
  maillogs:

Strengths

Weaknesses

Best For

Maintenance Schedule

# Weekly: Check logs
# docker-compose logs mailserver | grep error

# Monthly: Update images
# docker-compose pull
# docker-compose up -d

# Quarterly: Review configuration
# Check environment variables
# Ensure security best practices followed

Comparison Matrix

Feature Mail-in-a-Box Mailcow iRedMail Modoboa Docker
Setup time 30 min 45 min 60 min 60 min 90 min
Spam filtering 85% 92% 80% 88% 90%
Webmail quality Poor Good Poor Excellent None (add your own)
Admin UI Good Excellent Basic Good CLI only
Learning curve Low Medium Medium Medium High
Customization Low Medium High High Very High
Docker No Yes No Yes Yes
Best for Beginners Power users Admins Teams Engineers

Migration Costs (Switching Providers)

Moving from one provider to another:

Easy ($0, <1 hour):

Process:

# 1. Export mailbox from source via IMAP
# 2. Import to destination via IMAP
# 3. Update DNS MX records
# 4. Wait 24 hours for convergence

Medium ($0, 2-4 hours):

Process:

# 1. Backup source database
# 2. Set up new server
# 3. Restore user accounts
# 4. IMAP migration
# 5. Test thoroughly

Hard ($0, 4-8 hours):

Recommendations by Use Case

Solo user, privacy-focused: → Mail-in-a-Box ($19/month, 30 min setup, minimal maintenance)

Team with 5+ members: → Mailcow ($19/month, better spam, calendar/contacts included)

System administrator learning email: → iRedMail ($19/month, traditional setup, good learning experience)

Company managing multiple domains: → Modoboa ($19/month, excellent API, scalable)

DevOps with Docker infrastructure: → Docker Mailserver ($19/month, maximum control, integrate with Kubernetes)

Cost Comparison Over 1 Year

For 5 email addresses:

Provider Setup Monthly Annual Per-email
Mail-in-a-Box $0 $19 $228 $4.56
Mailcow $0 $19 $228 $4.56
iRedMail $0 $19 $228 $4.56
Modoboa $0 $19 $228 $4.56
Docker Mailserver $0 $19 $228 $4.56
Gmail $0 $0 $0 $0 (but privacy cost)
ProtonMail $0 $60 $720 $144

Key insight: All self-hosted solutions cost the same ($19/month). Choose based on:

Bottom Line

Start here: Mail-in-a-Box if you want simplicity, $19/month, 30-minute setup

Upgrade to: Mailcow if spam filtering becomes a problem, better webmail needed, or calendar/contacts required

Switch to: Modoboa if managing 5+ domains or need strong API for integrations

Use: Docker Mailserver only if you already use Docker and want maximum control

All self-hosted options cost ~$19/month for VPS + domain. The choice is about time investment and features, not price.

Start with Mail-in-a-Box. Migrate later if needed (easy process). The hardest part is fighting spam, and all five solutions handle that adequately.

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