Lately though, I've switched tact a bit and have resurrected some ~20yr old research called Behaviour Tree Engineering or Behaviour Trees, so I'm now writing specifications called BT specs.

e.g: https://bte.mills.io/s/v4Mjbyf0OBJWm5YRLwG5XiIH

For tools and architecture,I design data structures and let the LLM write the code, in small steps. Lots of discussion with the LLM. What Cory Doctorow calls centaur mode - a human mind augmented with a more powerful body. Applies to side projects and $DAYJOB.

For applications, I rewrote a framework of mine that I used 2003-2009. It is highly constrained so the LLM has few options to improvise. I can just tell it what features to add and it adds them without much in the way of slop. I still find code repetition which I just tell it to clean up.