I wish Python was further down this path— I experimented with adding annotations and the mypy checker to a bunch of code at my company, and it seemed hopeless.

I wish Python was further down this path— I experimented with adding annotations and the mypy checker to a bunch of code at my company, and it seemed hopeless. Most libraries didn't have annotations at all, or there were annotations being maintained by a third party in a separate pypi package, but the annotations were out of sync with the main project and thus blew up in weird ways. I feel for the people trying to develop these gradual systems but it's truly a herculean task, especially in the Python community that is now understandably so extremely shy about major breaking changes.