Zoomable architecture diagrams: https://www.ilograph.com/

Are these diagrams created manually, outside of the software system, or are they part of the code, evolving by necessity with the software system? In the first case (which I assume is true), they suffer from the same problem as documentation: they can't be trusted to be up to date.

Yes, that's true. They're defined using YAML (the source is available on the left-hand side of the sample diagrams). I've linked it because, at least from a visualization point of view, it's something that I'd like to have as a tool. Making it the source of truth, or at least a useful visualization layer on top of an actual codebase would be even better, I agree. I like that it's "zoomable" in a way that normal images aren't. Is there a word for what this tool is doing? Focusing maybe?

I've heard the phrase "semantic zooming" but it doesn't seem to be all that standard. I implemented something like this. Use the handles on top-right of each box to collapse it.

I have always thought that nested zooming was way underutilized as a UI capability, and this is maybe the prettiest implementation I've ever seen. I love how it focuses on one branch of the tree without hiding the context of the others. Really impressive. +1 auto-generating something like this from code. If you think of the breadcrumb navigation in a lot of IDEs, this is potentially a more human-friendly version of the same thing. I would run that VSCode extension, for sure.