Every greenfield project uses claude code to write 90+% of code. Every YC startup for the past six months says AI writes 90+% of their code. Claude code writes 90+% of my code. That’s today.

It works great. I have a faster iteration cycle. For existing large codebases, AI modifications will continue to be okay-ish. But new companies with a faster iteration cycle will outcompete olds ones, and so in the long run most codebases will use the same “in-distribution” tech stacks and architecture and design principles that AI is good at.