discourse

Discourse is an open-source forum and community discussion platform — a modern alternative to old-style internet bulletin boards or mailing lists, designed to feel more like a contemporary web application than a 1990s message board. The problem it addresses is that most community discussion tools are either clunky and outdated, hosted by someone else with no control over your data, or require expensive licensing. Discourse is completely free, fully open-source, and designed to be self-hosted on your own server.

The platform supports threaded discussion topics, real-time chat (like Slack), user trust levels that automatically promote reliable contributors and restrict spammers, email notifications and digests, a plugin and theme system for customization, and AI-powered features through an optional plugin. Content is structured around topics (threads) and replies, with a voting and reaction system. The search is full-text and fast. Administrators can manage categories, permissions, user groups, and site settings through a web interface without writing code. The backend is a Ruby on Rails API server that stores data in PostgreSQL, uses Redis for caching and real-time features, and serves a JavaScript single-page application built with the Ember.js framework.

You would use Discourse when you want to build a community around a product, project, or topic — for example, a support forum for software users, a discussion space for an open-source project, an online learning community, or a members-only club. It is a good fit when you want the look and functionality of modern social software but want to run it yourself rather than relying on third-party platforms like Reddit or Facebook Groups, and when you need full control over moderation, data, and customization.