I wrote a library for Go that makes functional programming with channels-as-streams very comfortable, for me[1]. There is a problem with needing to box and unbox variables from the 'empty interface{}' type all the time but it's a minor wart IMO.

It's a really small library that was made in response to my own intuition (similar to yours) that the Go standard library wasn't really embracing a functional style. I haven't used it in any major projects but for small one-off things it's proved pretty useful. It basically works like pipes on the command line.

1: https://github.com/eblume/proto