Assume that later models of the 747 were managed in Excel. No trolling: What is wrong with that? You can write insanely powerful software using (1) formulas on the sheet (which are essentially functional programming) and (2) imperative logic in VBA (HTTP calls, database calls, file system, etc.). For years, I used this model and wrote pretty powerful software. Sometimes, I miss it for the encapsulated system. These days, in "biz dev" (internal software), it seems like the Excel model was replaced with an Electron front-end (HTML/CSS/JS) with Java back-end.