Thanks for the suggestions! The most "complex" program I've written is "t2t", or "kinopio2md", or "arith" (small "compiler" that emits Python and Javascript and Common Lisp and WASM all at the same time). I guess "t2t", since I'm currently using it to rewrite 0D (1,400 Python LOC) in a VHLL which emits Python and Common Lisp ("real soon now") and Javascript ("future"). I wonder if I misunderestimate what is "complex" or not. Kinopio2md creates one program by using 3 languages as assembler (Prolog, Javascript, Bash). I cheat a lot - I use existing work (OhmJS, Prolog, Javascript, Bash, Python, etc.),,, but, then, I can,,, and, combining them makes me think of different ways to solve problems, ways I wouldn't think of when using function-based thinking only. Oh, maybe
Kagi.com is the most "complex" and "real" application of these ideas?