For me, it's: libcluster (automatic clustering with Kubernetes Service) + horde (distribute workload across cluster) + Kubernetes Deployment Whenever I need to

For me, it's: libcluster (automatic clustering with Kubernetes Service) + horde (distribute workload across cluster) + Kubernetes Deployment Whenever I need to upgrade, I perform a rollout, new OTP application instances perform a takeover, once it's done previous pods are taken down.