I use Ruby and Go in a complementary way.

I find myself choosing Go for:

- concurrency - memory footprint management - cpu speed - that nebulous feeling I want a program etched in stone (strongly typed)

I've written a lot of Api based clients. Read from a queue and update AWS permissions. Receive a callout from something and passing it along to somewhere else. Come to think of it, I've written a lot of queue-reading workers, some replaced existing Ruby workers for CPU or concurrency reasons.

I think in the space of having computers talk to computers Go is highly successful because it handles nearly everything with the standard library. So I find a lot of sdk's for specific platforms written in go that can get something going with the standard library and a single package for the platform.