Zulip (https://zulip.com/ https://zulip.com/) has been doing this for a long time. See this interesting blog post on how it was done: https://blog.zulip.org/20

Zulip (https://zulip.com/ https://zulip.com/) has been doing this for a long time. See this interesting blog post on how it was done: https://blog.zulip.org/2016/10/13/static-types-in-python-oh-mypy/ https://blog.zulip.org/2016/10/13/static-types-in-python-oh-...