The Cloud Native Computing Foundation has shaken the hand of its second graduate project this year, in the shape of container runtime containerd.

Containerd joins CoreDNS, Kubernetes, Prometheus and Envoy in the CNCF’s lineup of projects that have moved from incubation to graduate status. The project hit v1.0 a year ago, and is working towards v1.3, though there is no explicit deadline, and promises the addition of a Windows runtime.

Graduation means a project has demonstrated “thriving adoption, diversity, a formal governance process, and a strong commitment to community sustainability and inclusivity” the CNCF explains.

Containerd first emerged at Docker in 2014 as a lower-layer runtime manager for the Docker engine, but during its time in the CNCF incubator has become “an industry-standard container runtime focused on simplicity, robustness and portability with its widest usage and adoption as the layer between the Docker engine and the OCI runc executor”.

Containerd maintainer and Docker engineer Michael Crosby, wrote in a blog: “The primary goal of Docker’s donation was to foster further innovation in the container ecosystem by providing a core container runtime that could be leveraged by container system vendors and orchestration projects such as Kubernetes, Swarm, etc.”

He added, “ An important design principle for containerd was to have first-class support for Kubernetes without being exclusively tethered to it, opening the door for many use cases for containers such as developer desktop, CI/CD, single node deployments, edge and IoT.”

From Docker’s point of view, he continued, “containerd is the runtime component of Docker Engine, which makes it available to mainstream developers without having to change their workflow.”

He also noted within the Docker and Kubernetes communities, “there has been a significant increase in contributions from independents and CNCF member companies including Docker, Google, Alibaba, NTT, IBM, Microsoft, AWS and ZTE.” Since joining the CNCF, the project had gained four new maintainers and eight reviewers he added.