[dandotway]

In my undergrad computer science program, I implemented the rudiments of a very simple CPU using AND, OR, and NOT logic gates. I learned how to program microprocessors in assembly language. I learned how to implement a programming language interpreter. I implemented a compiler with a lex that tokenized its input stream and had a parser that built an AST from said tokens, and had a code generator that walked the AST and output a sequence of instructions. This was all covered in an undergrad CS program, not a Masters or PhD, so you don't have to be a genius at the level of John von Neumann to design programmable computational machinery from scratch using only the resources in your brain, because the geniuses like von Neumann already invented it in their brains instead, and good teachers at universities have found gentle ways to pass it from their brains into your brain.

The original FORTRAN '57 did not even have SUBROUTINE, FUNCTION, CALL, etc., for implementing subroutines. Those came with FORTRAN II in 1958, which was the main language Kemeny's original BASIC was based on in the early 1960s, but Kemeny changed FORTRAN II's DO loop to the easier to remember 'FOR I = 1 TO 42 ...'.

Knuth designed his original 1960s MIX computer using just pencil and paper, designed it to be easy to run programs using just pencil and paper.

If you yourself could not build a rudimentary BASIC or cut-down FORTRAN using only the resources in your brain and a sheet of paper with a pencil, you might be spending too much time working with overcomplicated programming tools that do not bring joy to your life.