Can you say more about the automated refactoring? How did it work? How was it triggered? How much human involvement was there? Are any parts of it public?
can't say too much about it because it mostly used a lot of internal tools, but it was a combination of writing per-file utilities to do specific code transforms (think something like libcst), and then a framework to scan the google codebase, find affected files, and apply the transforms to them.
yes, gated by human reviews based on who owned the code, unless they were completely trivial and then were gated by a single global approver. there were always humans in the loop though.
Ah makes sense. At another MAANG, there was a code mod template job with a half dozen subvariants. I recall using a variant that supported ripgrep piping to sed -i for a simple replacement mod. There were jobs properties controlling how many mods per diff and whether it needed human approval or not. I think I did one batched by 1000 running once every 2 weeks to keep noise down.
