[microtonal]

this whole new thing believed to have "never been done before";

Nobody with knowledge of sandboxing believed this, Virtuozzo and later OpenVZ had been on Linux for a long time after all. Virtuozzo was even from a similar time frame as FreeBSD jails (2000-ish).

The key innovation of Docker was to provide a standardized way to build, distribute, and run container images.

[alfiedotwtf]

Virsh had worked for a long time before docker came around, but yeah… you essentially had to build your own Docker-like infrastructure that only you were using