> what is the distinction between "system-level" and "application-level"? I think it mostly comes back to scope or encapsulation. I expect my host to provide f

> what is the distinction between "system-level" and "application-level"? I think it mostly comes back to scope or encapsulation. I expect my host to provide facilities external to my program (databases, sendmail, a webserver), and I expect to have control over the software libraries internal to my program. Perhaps you're also asking why APT or Yum, which are great at managing system-level package availability and versioning, couldn't be adapted for local use by applications. I'm not sure there's a good answer for that. Maybe it's just portability? If BlubLang runs on 9 platforms, then BlubPM needs to run on those same 9 platforms. It's probably easier to get there if BlubPM is written in BlubLang. > What happened in the past 10-15 years that changed the world so much that whereas before we ran our applications on top of the system, now we seem to want to run them in individual sandboxes, often inside of other sandboxes inside of other sandboxes? VMs? I once heard a terrible analogy to the effect that we used to treat servers like pets: we gave them cute names and we nursed them back to health when they got sick. Now we treat them like livestock: if one gets sick, you shoot it and get a new one. There's a hilarious send-up of hand-maintained systems in the "DevOps is Ruining My Craft" article at http://tatiyants.com/devops-is-ruining-my-craft/ http://tatiyants.com/devops-is-ruining-my-craft/ The more you isolate the applications from the host, the easier it is to redeploy them.