There's a page on C2 Wiki that I'm reminded of: "alternating hard and soft layers" as a pattern. And I think this pattern tends to develop throughout large, lon

There's a page on C2 Wiki that I'm reminded of: "alternating hard and soft layers" as a pattern. And I think this pattern tends to develop throughout large, long-lived systems. Shakeups like transitioning from native apps to the browser, or the replacement of the sysv init scripts with the much larger systemd, make some things "harder" and others "softer". So you want some dynamism throughout so that a layer change is possible, but you also want some static elements so that they do the existing work reliably. It's a cyclical process, and often terminates abruptly when some other piece of software comes up and replaces the existing one. I am finding, after spending some years locked into a static-minded viewpoint, a renewed appreciation for having dynamic types available. In the design phase, it assists in creating useful feedback about a system. Coming at it from a point of experience helps in avoiding abuse of reflection, metaprogramming etc. and keeping the basic structure and algorithm design simple and gradually discovering which techniques will move the system forward. What a static approach tends to do is "lock in" everything, like when a child grows up and their skeleton becomes rigid. If your desire is code with eternal youth, then it would make sense to avoid locking things in! But that might mean denying it some of the wisdom of old age.