IMHO complexity created by limited isolation facilities of virtualenv and the likes isn’t worth the resources you save by not just having a VM for each app you

IMHO complexity created by limited isolation facilities of virtualenv and the likes isn’t worth the resources you save by not just having a VM for each app you work on. The complexity arises from differing system-wide dependencies that are out of scope of various package managers or virtual environments, and from development environment (assuming we’re addressing the need to have multiple apps co-exist on one machine for development) not matching production.