[bjpbakker]

A capabilities system like pledge could be a way to safer use _existing_ packages. However, I think that it's not a very nice way to continue. Every application will end up doing its own capability pledging, and mistakes will be made. A lot.

Another approach could be to use an effect system like PureScript does. The main problem with Node.js packages is that any function you use can execute arbitrary code (such as wiping systems with an IP that is from the Russian region). Having an effect system in place the library author has no other means than to come forward with the side-effect, or code won't compile.