Isn't Go designed to fill this niche? It's supposed to be a low-level systems language, but with "friendlier" features than C, and built-in concurrency support.
They kind of recanted that statement and said they meant it for "web servers" and stuff like that. However I know there has been at least a window manager made in Go.
I don't think it's the best fit, but it's a lot better than many current solutions. I personally prefer Haskell for anything others would write in Go, however many may find Ocaml or Erlang to fit them better.
However I'm biased and believe that functional programming is a better fit, more bug-free, easier, and simpler for most use cases than imperative programming.
Before there was C, there was Pascal. You didn't have malloc in Pascal. At ETH Zurich the standard OS was written in Oberon: it ran directly on the hardware with a garbage collector collecting everything.
Go also has a very highly quality crypto implementation. It has all of the good-code features that gnutls lacks: comments that make sense, unit tests, automatic memory management (of course), useful types, etc.
I don't think it's the best fit, but it's a lot better than many current solutions. I personally prefer Haskell for anything others would write in Go, however many may find Ocaml or Erlang to fit them better.
However I'm biased and believe that functional programming is a better fit, more bug-free, easier, and simpler for most use cases than imperative programming.