Linux distribution provider CoreOS has raised $20 million Series A in a round led by Google Ventures for $12 million and a follow on from Kleiner Perkins Caufield & Byers, Fuel Capital, and Accel Partners. This comes after an initial $8 million led by Kleiner Perkins Caufield & Byers, Sequoia Capital and Fuel Capital.

Based in San Francisco, CoreOS offers a lightweight Linux distribution that is described as a radical departure from other popular Linux distributions, in that each version ships as a single unit, rather than as a collection of add-on packages.

CoreOS takes up about 40 percent less RAM than other Linux distros, making it appealing to those running large-scale data centers and cloud environments.

Despite being described as being “Docker centric” by some, the CoreOS fell out with Docker in late in 2014, launching what we described as “the container wars,” complete with Rocket, its own command-line tool for managing an app container, along with its container image format, discovery and runtime mechanism.

As part of the funding announcement, CoreOS also officially launched Tectonic, which combines the CoreOS operating system with their Rocket container technology along with a management system for those containers based on Google’s Kubernetes platform.

“Our technology is often characterized as Google’s infrastructure for everyone else” CEO Alex Polvi said in a statement. “Today we are excited to make this idea a reality by announcing Tectonic, a commercial Kubernetes platform. Tectonic provides the combined power of the CoreOS portfolio and the Kubernetes project to any cloud or an on-premise environment.”

Tectonic is said to pre-package all of the components required to build Google-style infrastructure and adds additional commercial features, including a management console for workflows and dashboards, an integrated registry to build and share Linux containers, and additional tools to automate deployment and customize rolling updates.

CoreOS noted that they have adopted Tectonic as a name for this release as it is a commercial product, which they wanted to remain separate from its open source components, including etcd, rkt, flannel, and CoreOS Linux.

Including the new round, CoreOS has raised at least $20 million to-date (figures were unavailable for seed rounds, Series A was $8 million.) Previous investors not participating in the new round include Andreessen Horowitz and Sequoia Capital.