From what I can tell, it's Python for the API server, Typescript for everything else. FWIW, Python servers like this are just a wrapper around `gunicorn` or so

From what I can tell, it's Python for the API server, Typescript for everything else. FWIW, Python servers like this are just a wrapper around `gunicorn` or some other performant low level tool. For some teams, it's easier to define a schema in Python for a couple years now due to some very innovative libraries with easy-to-use decorators. I have no personal experience with using it in production or for an extended amount of time however.