Usersnap - Usersnap is a customer feedback software for SaaS companies that need to constantly improve and grow their products.
i3 - A dynamic tiling window manager designed for X11, inspired by wmii, and written in C.
Redmine - Flexible project management web application
dwm - dwm is a dynamic window manager for X. It manages windows in tiled, monocle and floating layouts. All of the layouts can be applied dynamically, optimising the environment for the application in use and the task performed.
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.
Openbox - Openbox is a highly configurable, next generation window manager with extensive standards support.