Extremely impressive. I had a ZX81 when I was around his age, and was dimly aware of 'machine code', but couldn't quite get my head around doing anything subst

Extremely impressive. I had a ZX81 when I was around his age, and was dimly aware of 'machine code', but couldn't quite get my head around doing anything substantial with it - BASIC was where I mostly stayed. Moved to a 128, then later the PC world (a Sanyo 550 - almost PC compatible!), and mostly stuck with BASIC in those in the 80s. I did get in to some assembly stuff on the C128 side of things, as it came with a built-in assembler. I understood assembly basics, but didn't do much productive with it. I could move some boxes around the screen via keys, and I did do a bit with the '80 col' monochrome mode trying to do some custom sprite stuff (learned a lot about XOR) - but that's about as far as I got by my mid teens. Reading stories like the OP make me feel inadequate...