Agreed. I never really got hooked on Docker itself, but Swarm is well-scoped and easy to use without sacrificing too much; I'd argue the vast majority of k8s users would be better off with something simpler, and Swarm fits the bill nicely. Maybe Nomad does too, but IMO Hashicorp do a really bad job of documenting the progression from a localhost test to a production setup; the docs for each of their tools can be summarised as "draw the rest of the fucking owl".