Overview

WildDuck is an opinionated, modern email server written in Node.js by the creator of Nodemailer. It is designed as a scalable IMAP/POP3/LMTP server backed by MongoDB, favouring simplicity of design and an open data model over historical mail-server conventions.

Key Features

• IMAP/POP3/LMTP: modern server implementation in Node.js
• MongoDB Storage: mail stored as JSON documents with full-text search options
• REST Admin API: manage users, mailboxes, credentials and quotas programmatically
• Webhooks: receive notifications for new mail and message activity
• Scalable Design: built to scale horizontally across many users and nodes
• Built for Developers: designed by the Nodemailer author for custom, code-driven mail systems

Why Use It

WildDuck suits developers who want a mail server they can treat like a database-backed application. Its JSON storage, REST API and webhooks make it a strong choice for building custom mail products rather than operating a traditional mail stack.

Use Cases

• Building a custom mail product or multi-tenant email service
• Self-hosting email with a REST-driven, scriptable management layer
• Replacing a conventional mail server with an API-first, MongoDB-backed one

Platforms

Linux and other Unix-like systems (Node.js; deployed via npm or Docker).

Licence

Open Source — EUPL-1.2 (European Union Public Licence).

Website

https://wildduck.email/

Alternatives

• Mailcow — dockerised all-in-one mail server suite