Dokku's multi-server offering is based on k3s. We interact with k3s but offload any actual clustering to k3s itself as it does the job better than Dokku could :

Dokku's multi-server offering is based on k3s. We interact with k3s but offload any actual clustering to k3s itself as it does the job better than Dokku could :) You can also just tie Dokku into an existing K8s cluster on your favorite cloud provider instead. Disclaimer: I am the Dokku maintainer.