[hn_throw2025]

Great points in this thread, but I would say another advantage of Docker is that of documentation.

The Dockerfile is a description of a reproducible build, and a docker-compose.yml file documents how running services interact, which ports are exposed, any volumes that are shared, etc.

It’s all too easy for config knowledge to be siloed in people. I got the impression that the Author prefers tinkering with pet servers.

[rascul]

> The Dockerfile is a description of a reproducible build

It's not inherently reproducible but it can potentially be made so.

[ndsipa_pomu]

How is it not reproducible?

[rascul]

By default there is no assurance that any external resource you use is going to be the same every time. Whether that's another image, a package you install, etc. This is something you have to ensure yourself if you want it to be actually reproducible. Specifying a specific version or hash of an external resource can help get you there.

[ndsipa_pomu]

Thanks - that makes sense now. I was thinking of "reproducible" as in it does the same thing each time, but as you say, that can lead to different outcomes - usually updated or patched versions of base images etc.