pycontracts: https://github.com/AlexandruBurlacu/pycontracts

icontract: https://github.com/Parquery/icontract

The DbC Design-by-Contract patterns supported by icontract probably have code quality returns beyond saving work.

Safety critical coding guidelines specify that there must be runtime type and value checks at the top of every function.

I use TypeGuard too, but only in local dev and pytest runs. I find it really useful so I'm now intrigued to try Beartype too. I found the readme on GitHub confusing at a glance though, I need decorators to type check something?