I've personally been investing heavily in [Incus](https://linuxcontainers.org/incus/), which is the Linux Containers project fork and continuation of LXD post Canonical takeover of the LXD codebase. The mainline branch has been seeing some rapid growth, with the ability to deploy OCI Application Containers in addition to the System containers (think Xen paravirtualized systems if you know about those) and VMs, complete with clustering and SDN. There's work by others in the community to create [incus-compose](https://github.com/bketelsen/incus-compose), a way to use Compose spec manifests to define application stacks. I'm personally working on middleware to expose instance options under the user keyspace to a Redis API compliant KV store for use with Traefik as an ingress controller.

Too much to go into with what Incus does to tell you everything in a comment, but for me, Incus really feels like the right level of "old school" infrastructure platform tooling with "new school" cloud tech to deploy and manage application stacks, the odd Windows VM that accounting/HR/whoever needs to do that thing that can't be done anywhere else, and a great deal more.