Reading the section on ruby reminds me of the things that I take for granted in node.js right now owing to the long history of package management and module systems that it builds upon.

It's super nice having the dependencies specified by semvers in a package.json and installed locally in a project node_modules directory so that libraries can't step on each others toes.

The "Don’t use Bundler version X with RVM version Y" can be specified directly in the package.json and concurrent versions of module dependencies even work without incident in the same project.