openproject

OpenProject is the open source alternative. It covers traditional project management (waterfall, Gantt) and agile (Scrum boards, backlogs) in one tool.

GPL v3. Used by public sector organizations, universities, and companies that need on-premise project management for compliance reasons.

The Community edition is free and self-hosted. It includes work packages, Gantt charts, agile boards, wikis, forums, and basic time tracking. The Enterprise edition starts at $5.95/user/mo (cloud) or contact-for-pricing on-premise, adding features like project templates, custom fields on projects, BIM module, and two-factor auth.

The catch: OpenProject tries to do everything Jira does, and that means it's complex. The UI is functional but dense, not as slick as Linear or Plane. Self-hosting requires Ruby on Rails knowledge, PostgreSQL, and real maintenance. And the Community edition lacks some features teams expect as standard, like project templates and advanced custom fields.