Mantis is a free, popular web-based bug tracking system. It is written in the PHP scripting language and works with MySQL, MS SQL, and PostgreSQL databases and a Web server. Mantis has been installed on Windows, Linux, Mac OS, OS-2, and others. Almost any Web browser should be able to function as a client. It is released under the terms of the GNU General Public License (GPL).

Mantis is an issue tracker implemented in PHP. The main features include:

• Free GPL license
• Easy to install in both internally and in hosted environments
• Easy to evaluate
• InstantMantis, to be up and running in 2 minutes (not recommended for production use)
• Simple user experience
• Web-based
• Supports any platform running PHP: Windows, Linux, Mac, Solaris, AS400/i5, etc.
• Available in 68 localizations.
• Simple and advanced issue pages
• Multiple projects per instance
• Support for projects, sub-projects, and categories.
• Users can have a different access level per project
• Changelog support
• Roadmap
• My View page
• Search and filter
• Full text search
• Simple and advanced filters
• Shared filters across users and projects
• Built-in reporting using reports and graphs
• Custom fields
• E-mail notifications
• Users can monitor specific issues
• Attachments can be saved on server or in database, or can be backed up to an FTP account
• Issue change history
• RSS feeds of news, issues matching saved filters, and issues matching a specific project
• Customizable issue workflow
• Sponsorship support— Users are able to place bounties or sponsorships for specific issues, and developers can track sponsorships and payments
• Anonymous access
• Signup with Captcha and e-mail confirmation
• Self-service reset password support
• Export to CSV, Microsoft Excel and Microsoft Word
• Ability to extended functionality through hook (custom) functions.
• Report issues via e-mail (available as a patch, currently being integrated)
• Report issues via custom form on your Web site (Anonymantis).
• Source control integration (SVN and CVS).
• No limit on the number of users, issues, or projects.
• Wiki integration (optional)
• Time tracking
• Ability to send messages to other users
• Public and private projects—Public projects accessible to all users, private are only accessible to those specifically added.
• Public and private notes—Private notes are accessible to users with a specific access level to the relevant project
• Public and private issues—Private issues are accessible to users with a specific access level to the relevant project
• Public and private news—Can be associated with a specific project, or with all projects
• Issue relationships
• Issue relationship graphs (uses dot library).
• Attachment auto-preview
• Sticky issues—Always appear on the top of the issues list
• Group Actions—Actions can be applied on multiple issues
• Easy hyperlinks to issues and issue notes (e.g. #123 hyperlinks to issue number 123)
• Ability to view recently visited issues—last five visited issues are visible by default at the top right corner
• Authentication
• Default Mantis authentication (recommended)
• LDAP integration
• HTTP basic authentication support
• Active directory integration (patches available)
• Chat integration (optional)
• Multi-DBMS support—Mantis uses ADODB as an abstraction library to support multiple DBMSes
• MySQL
• MS SQL
• PostgreSQL
• Oracle (experimental)
• DB2 (in progress)
• Web service (SOAP) interface (MantisConnect)—a SOAP Web service implemented in PHP and can be consumed from any language that supports SOAP Web services.
• .NET client library
• Java client library
• Cocoa client library
• Eclipse plugin
• NAnt task
• Mantis notifier
• Support for mobile devices (MantisWAP).
• Online chat (optional integration)