Well Linux had containerization before Docker came along. The initial release of LXC was in 2008, a decent distance after Jails/Zones but still 5 years before Docker. OpenVZ was even earlier than that, starting in 2005

Even earlier was Linux VServer, which was 2001 :) So yeah, Linux containers have been around in one form or another for over a decade before Docker helped popularise things.

This makes some interesting reading: https://blog.aquasec.com/a-brief-history-of-containers-from-...

Lxc predates docker, and other lesser forms of containerization (or perhaps "precursors") like simple chroot have been around much longer.

Docker was originally written to use LXC for containerization. It wasn't until right before 1.0 that Docker was written to use its own go based library for container handling. https://blog.docker.com/2014/03/docker-0-9-introducing-execu...

What about OpenVZ (2005) ? It’s not containerizing application but whole VPS of course, but still.

I use it for more than a decade myself and I liked the simplicity of it.

Doesn't that require out of tree kernel patches?

It sure did back then, that was its biggest downside (not sure if it's still required today).

We used it extensively at my work in a Web company to package and deploy all our stack as far as 2006.