// the find
k3s-io/k3s
Lightweight Kubernetes
K3s is a CNCF-certified Kubernetes distribution that ships as a single binary under 100MB, with SQLite as the default datastore instead of etcd. It's aimed at edge, IoT, CI, and resource-constrained environments where running full upstream Kubernetes is impractical. This is a production distribution from Rancher/SUSE, not a toy — it passes the full Kubernetes conformance suite.
Single binary packaging with containerd, CoreDNS, Flannel, Traefik, and metrics-server bundled in — one curl command gets you a working cluster. SQLite as the default datastore eliminates the etcd operational burden for single-node or small clusters, while still supporting etcd, Postgres, MySQL for HA setups. Stays tightly coupled to upstream Kubernetes releases with a documented goal of patch releases within one week of upstream — you're not trading currency for convenience. The websocket tunnel for kubelet API removes the need to open inbound ports on worker nodes, which matters in constrained network environments.
SQLite default is fine for single-node dev use but becomes a footgun when teams promote a cluster to production without switching to a proper HA datastore — the documentation warns you but nothing stops you. Bundled Traefik and Flannel are opinionated defaults; replacing them (e.g., with Cilium and nginx-ingress) requires disabling built-ins and layering your own, which adds operational complexity that partly defeats the 'simple' premise. ARM support is present but historically has lagged behind x86_64 on tested configurations and available container images for bundled components — worth verifying your specific ARM variant before committing. Windows node support exists but is clearly a second-class citizen based on the number of `_windows.go` stub files that likely just return errors.