gLinux is a Debian Testing-based Linux distribution used at Google as a workstation operating system.
[1] The Google gLinux team builds the system from source code, introducing their own changes.
[2][3][4][5][6][7][8] gLinux replaced the previously used Ubuntu-based distribution, Goobuntu.
[9] gLinux is usually installed by loading into a bootstrap environment when it is first booted up.
Over the years, Google has focused on speed, scale and data, which is the thought process that allowed them to move to gLinux.