I believe GP misspoke; to my knowledge Deno does not allow you to set permissions on dependencies. It's not using object capabilities as far as I'm aware. I wish it were!
> There's nothing in place to stop a dependency from putting unsafePerformIO on blast.
import safe MyDependency
... but do you have to make sure that nothing in the tree is claiming to be Trustworthy. Which is actually pretty easy.
From your description it sounds like Deno is using object capabilities -- that's a great step forward.
> Many years ago npm inc treated download and package counts as KPI.
That's bonkers. I had no idea.