> What's the added complexity there, in terms of deployment?

You need to install the interpreter/runtime (and sync versions/use rbenv/etc) + you need to install your libraries + ensure that they are kept up to date (i.e. virtualenv or bundle install).

A lot of this is shortcut these days thanks to rbenv, virtualenv, etc, but it's still not automatic.

I can import a ton of libraries into my Go project on OS X, cross-compile a binary (`$ GOOS=linux go build`) and upload it. If I update the packages on my dev machine, it doesn't matter. Recompile, upload, restart. This goes for many languages that compile native binaries, but Go does make it really easy.