You can also look up for these other topics:
Framework
Coding Standards
Boilerplate
CMS
Tool
Security
Hacktoberfest
FreeScout — Free self-hosted help desk & shared mailbox (Zendesk / Help Scout alternative)
UVdesk Opensource Community Helpdesk Project built for all to make a Full Ticketing Support System along with many more other features.
Free and open-source web application for MSPs that streamlines IT documentation, ticketing, invoicing, and accounting, an alternative to ITGlue. It helps in managing and organizing client's IT informa
Laravel Ticket System, to help you manage your tickets easily.
Event Espresso 4 Core for WordPress: Build an Event Ticketing Website Today!