SimpleLogin — Open-Source Email Aliasing and Privacy Service

Introduction

SimpleLogin is an open-source email aliasing service that generates unique forwarding addresses for every site or service you sign up with. If an alias gets compromised or spammed, you disable it without affecting your real inbox.

What SimpleLogin Does

• Creates unlimited email aliases that forward to your real mailbox
• Allows replies from aliases so recipients never see your real address
• Blocks spam by disabling or deleting compromised aliases
• Supports custom domains for branded alias addresses
• Integrates with browser extensions and mobile apps for quick alias creation

Self-Hosting & Configuration

• Requires a domain with MX records pointed at your server
• Deploy with Docker Compose using the provided configuration
• Configure Postfix or any SMTP relay for outbound mail delivery
• Set up DNS records (SPF, DKIM, DMARC) for reliable email delivery
• PostgreSQL database stores alias mappings and user accounts

Architecture Overview

SimpleLogin is a Python Flask application backed by PostgreSQL. Inbound emails arrive via Postfix, which pipes them to the application for alias resolution and forwarding. Outbound replies are routed through the same Postfix instance with DKIM signing. The web UI and API handle alias management, and browser extensions call the API for one-click alias creation.

Key Features

• Unlimited aliases with per-alias enable/disable controls
• PGP encryption support for forwarded emails
• Custom domain support with automatic DNS verification
• REST API and browser extensions for seamless alias generation
• Activity dashboard showing forwarded, blocked, and replied message counts

Comparison with Similar Tools

• Firefox Relay — limited free aliases and Mozilla-hosted only; SimpleLogin is self-hostable with unlimited aliases
• AnonAddy (addy.io) — similar feature set; SimpleLogin has a more polished UI and Proton Mail integration
• Apple Hide My Email — Apple ecosystem only; SimpleLogin works everywhere with any email provider
• Fastmail masked emails — tied to Fastmail subscription; SimpleLogin works with any mailbox

FAQ

Q: Can I send emails from an alias? A: Yes. You reply to the forwarded email and SimpleLogin routes the reply through the alias address.

Q: Does self-hosting require a static IP? A: A static IP with proper reverse DNS is recommended for reliable email delivery.

Q: Is SimpleLogin affiliated with Proton Mail? A: SimpleLogin was acquired by Proton AG in 2022. The project remains open source under the AGPL license.

Q: Can I use my own domain for aliases? A: Yes. Add your domain, configure DNS records, and create aliases like anything@yourdomain.com.

Sources

• https://github.com/simple-login/app
• https://simplelogin.io/docs/