= communication tool tailored specifically to meet the needs of bottom up grassroots organizing
"Crabgrass is a software libre web application designed for social networking, group collaboration and network organizing. Our goal is to create communication tools that are tailored specifically to meet the needs of bottom up grassroots organizing. By social networking, we mean the ability of users to get to know one another through their online contributions and presence. By group collaboration, we mean the ability of small groups to get things done, such as share files, track tasks and projects, make decisions and build repositories of shared knowledge. By network organizing, we mean the ability of multiple groups to work together on projects in a democratic manner." (https://we.riseup.net/crabgrass/about)
"Crabgrass currently consists of a solid suite of group collaboration tools, such as private wikis, task lists, file repository, and decision making tools. We are currently working on better social networking tools, blogs, and event calendars, as well as better support for collaboration and decision making among independent groups." (https://we.riseup.net/crabgrass/about)
"As Free Software, anyone is welcome to check out the code (git clone git://labs.riseup.net/crabgrass.git) and follow the development howto, run their own site with it, and contribute improvements and changes to the source code."
Crabgrass is written in Ruby using the Ruby on Rails framework.