[concerned_user]

Because proptypes actually catch stuff during runtime, flow not so much. Maybe I have a wrong setup, but that is the case for me.

[aviraldg]

There's a Babel plugin that transforms your code to do runtime typechecks based on your Flow type annotations: https://codemix.github.io/flow-runtime

[markl42]

If you already have static type checking, is that not enough? Are there scenarios where proptypes will throw/show warnings at runtime that flow wasn't able to catch at build time?