- [osTicket](https://osticket.com/) - Manage, organize and archive all your support requests and responses in one place. ([Source Code](https://github.com/osTicket/osTicket)) `GPL-2.0``PHP`
- [OTOBO](https://otobo.de/en/) - Flexible web-based ticketing system used for Customer Service, Help Desk, IT Service Management. ([Demo](https://otobo.de/en/open-source-ticketing-system/#demos), [Source Code](https://github.com/RotherOSS/otobo)) `GPL-3.0``Perl`
- [Pachno](https://pach.no/) - Bring your team together to design, build and deliver your project with a tool that works with you and your team, and adapts when you need to. ([Source Code](https://github.com/pachno/pachno)) `MPL-2.0``PHP`
- [Peppermint](https://peppermint.sh/) - A simple ticket management tool with support for logs and multi-deployment. ([Source Code](https://github.com/Peppermint-Lab/peppermint)) `AGPL-3.0``Docker`
- [Roundup Issue Tracker](https://www.roundup-tracker.org/) - A simple-to-use and -install issue-tracking system with command-line, web, REST, XML-RPC, and e-mail interfaces. Designed with flexibility in mind - not just another bug tracker. ([Source Code](https://www.roundup-tracker.org/code.html)) `MIT/ZPL-2.0``Python`
- [Trudesk](https://trudesk.io/) - Trudesk is an open-source help desk/ticketing solution. ([Source Code](https://github.com/polonel/trudesk)) `Apache-2.0``Nodejs`