Nice! Nim has been great for us - fast to code in and even faster once compiled! We're using it for the backend and microservices at https://cxplanner.com and loving it.
One of the reasons for choosing Nim was the ease of getting a production ready web backend. For the core part of managing the backend we are using existing Nim libraries [1], and they are easy to expand and work with. I cannot give you a comparison with Go since I haven't managed that large Go projects - but for Nim we are all into the async and threading. I think the channels within the threading is hardest part in Nim, but work is being done it.
Have a look at Jackson from https://boxyhq.com . Spin up one container and a couple of simple endpoints - voila, up and running. And a really cool team too!