MyBB

MyBB is an open-source forum platform written in PHP that provides a full-featured discussion system for online communities. It includes a plugin system, theme/template editing, moderation tools and support for multiple SQL backends. (mybb.com)

Key Features

• Advanced plugin system for extending functionality and integrations.
• Built-in theme and template editor for customizing layout and design.
• Moderation and administration tools (moderator controls, user/group management, reporting).
• Private messaging and user-to-user communication features.
• Supports MySQL/MariaDB, PostgreSQL and SQLite backends.
• Lightweight, efficiency-focused PHP codebase with Composer metadata present. (mybb.com)

Use Cases

• Creating community discussion forums for products, hobbies, or interest groups.
• Self-hosted customer support / help forums with moderator workflows.
• Private or invite-only communities requiring fine-grained user/group controls.

Limitations and Considerations

• Official documentation lists very low historic minimums (PHP ≥ 5.2), but deploying on modern, supported PHP versions is recommended for security and performance. (docs.mybb.com)
• Core is a traditional PHP codebase (many procedural PHP files) rather than a modern PHP framework; some administrators or developers may need to adapt practices when integrating modern tooling. (github.com)
• Official site does not provide an official hosted demo; third-party demo instances and theme marketplaces exist but vary in maintenance and features.

MyBB is a mature, community-driven forum platform suitable for a wide range of discussion and support scenarios. Its plugin/theme ecosystem and multi-database support make it flexible for self-hosted deployments.