K3s — Lightweight Kubernetes

Use this skill when deciding whether to run containers with plain Docker/Compose, K3s, or a larger Kubernetes platform, and when writing K3s manifests for edge devices, homelabs, small production clusters, workers, CronJobs, shared storage, Redis/Valkey, autoscaling, or external secret-manager integration.

K3s is a CNCF-certified, lightweight Kubernetes distribution packaged as a small single binary. It defaults to SQLite for single-server clusters and bundles useful components such as containerd, Flannel CNI, CoreDNS, Traefik ingress, ServiceLB, local-path-provisioner, and a network-policy controller.

Detailed decision matrix and caveats: references/decision-and-operations.md. Starter manifests:

• templates/simple-device.yaml — one edge device with host device access.
• templates/web-workers-cron-valkey.yaml — web app, multiple worker deployments, CronJob, shared Valkey, PVC.
• templates/external-secrets-vault.yaml — External Secrets Operator + Vault-style SecretStore scenario.

First decision: Docker, Compose, K3s, or bigger Kubernetes?