Docker has long anticipated placing containerd, a core piece of the Docker runtime, under the stewardship of a third-party group.
Now the official word is out: Docker is submitting containerd to the Cloud Native Computing Foundation -- a consortium of companies, Docker included, responsible for the governance of several key projects for the open source ecosystem of containers running in the cloud.
The move lets Docker to focus on what it does right -- run a corporation that monetizes container technologies for the enterprise -- and allow the underlying open source technology to be developed at a pace and in a context that best suits it.
Give away the good stuff
Containerd is a mechanism for booting, running, and managing external interfaces for containers. Ever since since version 1.11, Docker has used containerd as a core piece, along with with runC, an open source component that spins up containers. The Docker app communicates with containerd; containerd talks to runC.
Docker has historical precedent for how it's handling containerd. Back in 2015, Docker donated runC to the then-newly minted Open Container Initiative (OCI) so that it could be used by other companies, including competitors like CoreOS. Thus, anybody who wants to build a piece of the container ecosystem isn't hidebound by one company's approach.
For Docker (the company), this was part of an ongoing effort to shed an image that the container ecosystem has been dictated largely by the technical direction of Docker (the product). Spinning off and donating runC was one step toward that goal. Doing the same for containerd was the next step, and it could be even more significant.
Home sweet home
What made Docker pick the CNCF rather than the OCI as a home for containerd? In today's announcement, Docker said the CNCF is "an organization where a focus on containerization is front and center." It already oversees Kubernetes, a project that goes with Docker these days the way peanut butter goes with jelly, and other CNCF projects further complement that pairing.
The choice of the CNCF makes sense when you look at what the organization has worked on. OCI, container-focused as it is, has been more about specifications for container runtimes and image formats. CNCF is more about projects, including implementations of those specifications.
Docker has said it wanted to put containerd under the auspices of a "neutral foundation." The CNCF features Docker as a platinum member, but it's one of several organizations at that tier, and the group's governing board and technical oversight committee each only feature one representative from Docker. That said, it's still possible that Docker's sheer weight in the marketplace as the go-to commercial solution for containers will continue to tilt its way.