Open-source alternatives to Email

Inline styling for html mail in golang

MailHog SMTP Protocol

Lightweight SMTP client written in Go

A simple CSS parser and inliner in Go

DKIM package for golang

This is a Ruby email library providing a comprehensive toolset for composing, parsing, and sending emails. It includes an SMTP client for delivering outgoing messages and a MIME parser for decomposing complex multipart email structures. The project features an IMAP and POP3 mail fetcher for synchronizing messages from remote servers, alongside a specialized framework for testing email logic through mock delivery methods and matchers. The library covers a broad range of email operations, including the generation of nested multipart messages, the management of attachments, and the translation

Golang package for send email. Support keep alive connection, TLS and SSL. Easy for bulk SMTP.

Mox is a self-hosted email server that runs as a single compiled Go binary, handling the full lifecycle of sending and receiving email through SMTP, IMAP4rev2, and a built-in webmail application. It is designed to be operated without external dependencies or runtime plugins, with all mail services — including spam filtering, queue management, and web interfaces for administration and account management — contained in one executable. The server distinguishes itself through automated TLS certificate management via ACME, DNS-based autoconfiguration for email clients, and file-based configuration

Using Mailchain, blockchain users can now send and receive rich-media HTML messages with attachments via a blockchain address.

Maddy is a modular mail server that assembles a complete email system by connecting small, single-purpose modules through a declarative configuration file. Rather than a monolithic stack, it lets operators compose message processing, storage, authentication, and security enforcement from interchangeable building blocks, with each module handling a specific function like receiving SMTP connections, verifying credentials, or applying policy checks. The server distinguishes itself through its flexible authentication and security architecture. It delegates user verification to external systems in

:whitecheckmark: A Go library for email verification without sending any emails.

Go library for the Mailgun API.

Roundcube is an open-source, self-hosted webmail client designed for reading, composing, and organizing emails stored on remote servers using IMAP and SMTP protocols. It provides a browser-based interface that allows users to manage their mailboxes and sender identities through a secure communication platform. The platform is distinguished by its modular architecture, featuring a plugin-based extension system for adding new functional modules and a skin-based theme layer for customizing the visual appearance and responsive layouts. It further supports embedding its interface into external clo

AI Powered Email Aggregation Client | AI识别的邮件聚合客户端

The express way to send mail from Ruby.

django-yubin

A cute temporary email service built with NextJS Cloudflare technology stack 🎉 | 一个基于 NextJS Cloudflare 技术栈构建的可爱临时邮箱服务🎉

html emails and attachments to any smtp server with nodejs

This project provides a full-stack, containerized mail server platform designed for self-hosting. It functions as a complete mail transfer agent that bundles essential services—including SMTP, IMAP, and POP3—into a unified environment. By leveraging container orchestration, it enables the deployment of private email infrastructure that handles message transport, delivery, and user management within a single, manageable service. The platform distinguishes itself through deep integration with container runtimes and robust configuration flexibility. It supports granular customization via configu

djmail

This library has been designed to be independent of whatever HTTP request library or runtime you choose or wish to use, and you can install for all targets by running:

Mini SMTP server written in golang

This project is a Node.js email templating engine and SMTP delivery framework used for creating, rendering, and sending custom email templates. It provides a comprehensive suite for email orchestration, including a system for dispatching templated messages and a tool for generating custom layouts to standardize outbound messaging. The framework includes a dedicated HTML CSS inliner that converts external stylesheets into inline styles for consistent rendering across different email clients. It also features a multilingual localization tool for translating template text and subject lines, and

Temporary email 临时邮箱 smail