Mail-in-a-Box

One-click, self-hosted email server that just works

Mailpit

Fast, zero-dependency email testing tool for developers

Mailtrain

Self-hosted newsletter platform with advanced automation and segmentation

Mailu

Fully featured Docker‑based mail server that's simple to deploy

Manba

Unified HTTP API gateway with traffic control and plugins

Manticore Search

Fast open-source database built for high-performance search

MapServer

Powerful CGI engine for creating web‑based GIS maps and services

Mara Pipelines

Lightweight Python ETL framework with PostgreSQL and web UI

marimo

Reactive Python notebooks that stay reproducible, git‑friendly, and deployable

Marquez

Centralized metadata service for data lineage and lifecycle

Mastodon

Self‑hosted, federated microblogging platform powered by ActivityPub

Mastra

TypeScript framework for building scalable AI agents and workflows

Matano

Serverless security data lake for AWS with detection-as-code

Materialize

Real-time SQL platform delivering up-to-the-second data views

Mathesar

Spreadsheet interface for PostgreSQL databases, self-hosted and collaborative

Matomo

Self-hosted web analytics platform with complete data ownership

Mattermost

Secure, extensible team collaboration platform for modern workflows

Mautic

Open source marketing automation software you control completely

Maxun

Train a web‑scraping robot in minutes, no code required

Medama

Self-hosted, cookie-free analytics with a sub-kilobyte tracker

Medusa

Composable commerce platform with customizable building blocks

Meilisearch

Lightning-fast search engine with hybrid AI-powered search capabilities

meli

Open source platform for deploying static sites and frontends

Meltano

Declarative code-first data integration engine for modern pipelines