containerd is a widely used container runtime with an emphasis on simplicity, robustness and portability. It is available as a daemon for Linux and Windows, which can manage the complete container lifecycle of its host system: image transfer and storage, container execution and supervision, and low-level storage, etc..
containerd is designed to be embedded into a larger system, rather than being used directly by developers or end-users. containerd will serve as a core container runtime for the CNCF ecosystem.
The containerd community is growing with 70 contributors overall and an active contributor base with 17 unique contributors a month(average) and 7 new contributors in the past 30 days, as of 3/15/2017.
* vendor - https://github.com/docker/containerd/blob/master/vendor.conf (exact version at time of this PR https://github.com/docker/containerd/blob/6089c1525b665876307d43fb94f9e8ed76eb40a1/vendor.conf)
containerd is the most widely used container runtime, which is a critical building-block for cloud-native computing and is highlighted in the [CNCF charter](https://www.cncf.io/about/charter/). It intends to provide a container runtime for projects like Docker and Kubernetes that provide execution platforms for cloud-native applications.