Quoting:

    In the last few weeks I’ve been working my way
    through the excellent book Elements of Computing
    Systems - building a modern computer from first
    principles as part of the equally excellent Nand
    to Tetris MOOC.
       ^^^^^^

I guess you're not aware of the "From NAND to Tetris" book and series.

There is a course [1] where you learn from basic circuits design through writing a programming language until you use that language to write tetris. It is called nand2tetris. I can only assume the author will describe that course or its contents.

A friend of mine took the course, said it was great.

[1 ]http://www.nand2tetris.org

It's referring to this book: http://www.nand2tetris.org