The origins of patterns in software are actually from architecture. Code is just a medium that we work with, but they've been used in other fields for millennia.

Plus patterns in software are not all about managing complexity, and only some of them are about code construction. Like, do you know what the pattern is before you debug anything?

They're heuristics, basically.

In any case, a good ux pattern would be a top nav, but not fixed to the top.