Redmine

Redmine is a flexible project management web application that supports multiple projects from a single install. Each project gets its own issue tracker, Gantt chart and calendar, wiki, forums, news, and document and file storage, with role-based access control deciding who can do what.

Issue tracking sits at the core, backed by custom fields for issues, time entries, projects, and users, time tracking, and email notifications. Issues can be created by email, and the source code browser integrates with SVN, CVS, Git, Mercurial, and Bazaar. LDAP authentication, user self-registration, and translations in many languages round out the setup.

Written in Ruby on Rails, Redmine is cross-platform and cross-database and is built and maintained by community volunteers. It is released under the GNU General Public License v2.