I share the opinion of the person you are asking this question to and I can share my list of languages I delivered production systems in: Scala, Erlang, Java, Ruby, Python. In the past life C# (.net on Windows).

Now 4 years of golang. It beats all of them at development pace and ease of integration, especially since modules are working as they should. The killer features of golang: modules, http stuff, channels, ssh in stdlib, fantastic, easy to use crypto.