[interroboink]

FreeBSD has had jails since version 4 (~year 2000), fwiw.

Much of the technology was there, but Docker was able to achieve a critical mass, with streamlined workflows. Perhaps as much a social phenomenon as a technical one?

[Yeroc]

I think the real genius of Docker was the image packaging. The pieces were there but delivery and scripting it all wasn't easy.

[disagr]

BSD jails were no harder to automate than Docker; setup many ci/cd pipelines into jails in the 00s for a variety of applications.

They're way closer to the usual "Unix" tool feel too. Docker feels 100% like an attempt to get rich by engineering a monolith rather than be a few helper C tools. Docker was so annoying to learn.

Fortunately with the end of ZIRP and SaaS deflation (in real user terms, not fake investment to project we still live in the 2010s heyday), software engineers are focused on engineering more than hype generation. Am excited about energy based models, capture of electromagnetic geometry of the machine as it runs programs.

60s style lexical state management systems dragged forward in time because of social momentum have little to do with engineering. Are hardly high tech in 2025.

[mikepurvis]

Indeed. Even to this day, debootstrap feels a bit arcane and unapproachable, particularly relative to `docker pull ubuntu`.

[oftenwrong]

Don't discount the technical innovation required to integrate existing technologies in a novel and useful way. Docker was an "off the shelf" experience unlike any other solution at the time. You could `docker run ...` and have the entire container environment delivered incrementally on demand with almost no setup required. It did have a social factor in that it was easy for people to publish their own images and share them. Docker Hub was provided as a completely free distribution service. The way they made distribution effortless was no doubt a major factor in why it took off.

https://www.youtube.com/watch?v=wW9CAH9nSLs

[magicalhippo]

I used FreeBSD on my firewall in the early 2000s, and on my NAS from around 2007 till last year.

The big pain with jails for me was the tooling. There was a number of non-trivial steps needed to get a jail that could host a networked service, with a lot that could go wrong along the way.

Sure a proper sysadmin would learn and internalize these steps, but as someone who just used it now and again it was a pain.

Way down the line things like iocage came along, but it was fragile and not reliable when I tried it, leading to jails in weird states and such.

So I gave up and moved to Linux so I could use Docker.

Super easy to spin up a new service, and fairly self-documenting as you just configure everything in a script or compose file so much less to remember.

Initially in a VM on Bhyve, now on bare metal.

It feels a bit sad though, as jails had some nice capabilities due to the extra isolation.

[tkcranny]

Yeah it really was a social phenomena. Ten years ago conferences were swarmed with docker employees, swag, plenty of talks and excitement.

The effort to introduce the concepts to the mainstream can’t be understated. It seems mundane now but it took a lot of grassroots effort and marketing to hit that critical mass.

[jayd16]

There was clear incremental progress. Some of it can be seen in how mobile app isolation shook out as well.