Hey bcherny! Yes, dog-fooding (self-hosting) has definitely been a huge part in making TypeScript's development experience as good as it is. The upside is the breadth of tests and infrastructure we've already put together to watch out for regressions. Still, to supplement this I think we will definitely be leaning a lot on developer feedback and will need to write more TypeScript that may not be in a compiler or language service codebase. :D
Interesting! This sounds like a surprisingly hard problem to me, from what I've seen of other infra teams.
Does that mean more "support rotations" for TS compiler engineers on GitHub? Are there full-stack TS apps that the TS team owns that ownership can be spread around more? Will the TS team do more rotations onto other teams at MSFT?