It definitely a scary proposition. But it's worth mentioning that two of the world's biggest money moving platforms (Stripe and Shopify) are written in ruby.
It should be mentioned that their reasons were mainly developer convenience/productivity, and not “correctness”.
I think people severely overrate the value of the language when it comes to avoiding bugs. We already know how to minimize bugs: Extensive testing regimes (automated, manual, or both) and a general focus on correctness over “shipping on an artificial deadline”.
You can have something that aids convenience/productivity and not correctness. You can also have something that aids correctness that increases developer convenience/productivity. I treat static typing as the latter.
Edit: Btw, the github.com/sorbet/sorbet project is really well run and surprisingly easy to get into. I've been drafting PRs. C++ is not nearly as rough as I remember from decades ago.
Yup, also being used at Shopify. Types are awesome, but these companies got very far by betting big on the productivity of ruby before this became a concern.
Not claiming that ruby isn't productive, but I could as well rephrase that into "these companies got very far despite the lack of productivity of ruby before this became a concern". It's not really giving any new insight.