Odoo
The giant of Open Source ERPs. Powerful but complex, with a significant feature gap between the Free Community edition and the Paid Enterprise version.
Business Ops
ERPNext
The 100% Open Source alternative to Odoo. A monolithic ERP with Accounting, HR, and Manufacturing included out of the box.
Mautic
The open-source marketing automation platform. A powerful, self-hostable alternative to HubSpot and Marketo for creating personalized customer experiences.
Zammad
A modern, fully open-source helpdesk and customer support system that unifies email, chat, and social channels into a single interface.