Zammad
5.7k
Easy to use but powerful open-source support and ticketing system.
Ruby
MantisBT
1.8k
Bug tracker, fits best for software development.
PHP
Request Tracker
1.1k
Enterprise-grade issue tracking system.
Perl
ITFlow
947
Client IT documentation, ticketing, invoicing and accounting for MSPs (Managed Service Providers).
PHP
Bugzilla
834
General-purpose bugtracker and testing tool originally developed and used by the Mozilla project.
Perl