MantisBT

MantisBT is a very popular web based bug tracking tool (covering anomalies, upgrade requests, service requests and more) that is suited to any type of project. Kenzaburo Ito, who launched the project in November 2000, was soon joined by Jeroen Latour, Victor Boctor and Julian Fitzell in 2002; the four now form the core development team for the product.

MantisBT allows for project based ticket allocation. Requests can also be classified using a variety of criteria (type, category, severity, priority, public/private, etc.). In particular, the tool offers functionalities like a customisable status chaining workflow, a notification system, a filtered ticket search form, a personalised page for each user that lists the tickets they opened and those assigned to them, user rights management, an admin section for each project in which users can be added/deleted, sub-project creation and more.
MantisBT is distributed under the GNU GPL v2.
MantisBT is developed in PHP and requires the use of a database (MySQL, PostgreSQL, MS SQL). It has primarily been tested for Web Apache and IIS servers.