I would suggest looking at OpenStack and KVM or XEN for the hypervisor.

You also have Proxmox.

I’ve just checked the last commit for an active branch was last week, the last merge to the main branch was in march, this was just before their latest release.

Looks like it’s still actively being look after, but even if it didn’t have recent commits it’s open source and It’s not unusual for people to take time to work on things.

That totally sucks, are you in a customer facing role or is it just the office culture?