Yes, that's me. :) Kragen didn't see Ichbins until later. My favorite things about Ur-Scheme are that the code is clean, as you say, and he wrote up the lesson

Yes, that's me. :) Kragen didn't see Ichbins until later. My favorite things about Ur-Scheme are that the code is clean, as you say, and he wrote up the lessons learned at some length. No files: I think he meant not yet implementing primitives like open-input-file. Macros you can get by without: I used to use an R4RS Scheme system of my own without them, except sometimes I'd call on a dumb defmacro expander as a preprocessor. Kragen also wrote https://github.com/kragen/stoneknifeforth https://github.com/kragen/stoneknifeforth which I haven't read as much of. FWIW I also wrote this about a sort of self-hosting Python in Python: https://codewords.recurse.com/issues/seven/dragon-taming-with-tailbiter-a-bytecode-compiler https://codewords.recurse.com/issues/seven/dragon-taming-wit... -- as a bytecode compiler it's not too big but it depends on the giant Python runtime.