ctlptl vs k3d

ctlptl is a free command-line tool for declaratively configuring local Kubernetes clusters with YAML. Its main commands show running clusters, create them, apply configuration, and delete clusters along with their state. The project lists Docker Desktop, KIND, Minikube, and K3D, with registry support for KIND, Minikube, and K3D. Configuration can allocate CPUs and set up local registries; Minikube supports per-cluster Kubernetes version selection. ctlptl can also create a cluster on a remote Docker host, a capability the project describes for CI environments. Installation options include Homebrew for macOS and Linux, Scoop for Windows, Go install, Docker, and prebuilt release binaries. A Docker image containing recent kind and ctlptl versions is offered for CI. The project supports macOS, Linux, and Windows and is licensed under Apache License 2.0. Its README calls it a work in progress and says it is not meant for remote clusters or remote development sandboxes. Usage statistics are anonymized, with an opt-out command available.

k3d is a free, community-driven wrapper that runs k3s, Rancher Lab’s minimal Kubernetes distribution, inside Docker. It creates single-node and multi-node clusters for local Kubernetes development and can support hot-reloading, Tilt build-deploy-test workflows, and Drone CI service use. Docker is required, while kubectl is used to interact with clusters. For k3d v5.x.x, the overview specifies Docker v20.10.5 or later and runc v1.0.0-rc93 or later. A registries.yaml file configures registries, authentication, and certificates, and documentation covers local registries managed by k3d. Services can be exposed through Ingress or NodePort by mapping container ports to the host. Covered k3s integrations include CoreDNS, local-path-provisioner, Traefik, and the Klipper service load balancer. Installation options include release binaries, Homebrew, AUR, Chocolatey, Scoop, arkade, asdf, and Go. k3d runs on Linux, macOS, Windows, and self-hosted setups. It is not an official Rancher (SUSE) product.