What are some alternatives?
GitHub - Originally founded as a project to simplify sharing code, GitHub has grown into an application used by over a million people to store over two million code repositories, making GitHub the largest code host in the world.
Kanboard - Kanboard is a free and open source Kanban project management software.
GitLab - Create, review and deploy code together with GitLab open source git repo management software | GitLab
Trello - Infinitely flexible. Incredibly easy to use. Great mobile apps. It's free. Trello keeps track of everything, from the big picture to the minute details.
Jira - The #1 software development tool used by agile teams. Jira Software is built for every member of your software team to plan, track, and release great software.
Wekan - The open-source Trello-like kanban (built with Meteor)