Chromium OS is open source: https://www.chromium.org/chromium-os https://www.chromium.org/chromium-os. OverlayFS is in the upstream Linux kernel. CoreOS is a v

Chromium OS is open source: https://www.chromium.org/chromium-os https://www.chromium.org/chromium-os. OverlayFS is in the upstream Linux kernel. CoreOS is a very similar idea, and given that, we don't make builds of the container images available outside GCE. Customers who need specifics of the OS (that they can't find them by just looking at the kernel config on the node) are welcome to ping us a support ticket.