For me, I think the most appropriate metaphor is that it is the “workbench.” Or, the supercharged REPL: a computational notebook or a literate programming environment.
I’ve always gravitated towards things where I can work incrementally: Lisp, Lua, Jupyter notebooks, R-Studio markdown, etc. I’ve even gone so as far as making an environments where I can incrementally program and test C code, to emulate a notebook-like interface.
The other thing that I like, and you even mention this in the workbook section: it gives me the capability to build it as I need. That’s the Forth and Lisp creed. Or roughly, Unix creed. Do one thing and do it well - which I’ve always interpreted as, build only the thing you need.
It’s the peeve I have with other computer scientists or software engineers. They try to solve everyone’s problem, but end up either solving no one’s or doing it really badly.
So - yeah - Decker scratches the itch just right for me.