Mac OS X Mavericks, rbenv, and ruby-build “Missing the OpenSSL lib?”

openssl version: 1.0.1i, rbenv version: 0.4.0, ruby-build as plugin in the ~/.rbenv/plugins directory. The version of openssl on a Mavericks machine got out of sync with rbenv and ruby-build for some reason. For every attempt at installing a ruby version through rbenv attempted, we got the following message: “The Ruby openssl extension was not compiled. […]