taskjuggler

https://github.com/taskjuggler/TaskJuggler

TaskJuggler is a modern and powerful, Free and Open Source Software project management tool. It's new approach to project planning and tracking is more flexible and superior to the commonly used Gantt chart editing tools. TaskJuggler is project management software for serious project managers. It covers the complete spectrum of project management tasks from the first idea to the completion of the project. It assists you during project scoping, resource assignment, cost and revenue planning, risk and communication management.