This is not what you're asking for, but I think city as a visual metaphor for certain class of programs could work. Imagine literal factories for manufacturing certain class of objects, highways and roads to represent connections between component buildings, warehouse as databases or storage, office buildings as manager objects, etc and code editing is just moving buildings around (probably hard to do fine grained ed…
Cities work because they're organic and adaptable. You couldn't plan a city, much less understand all of it.