I am still tinkering with the Nim programming language, and quite enjoying it. I find the language to be well thought out, and it's very easy to build little libraries which have unit tests included in them. I like that idea.
But I have noticed that the binaries can be quite a lot bigger than my equivalent C programs, which I suppose is to be expected. So I have also been experimenting with the UPX packer which helps to keep the file size down ... this could be useful if you want to run your Nim programs on something tiny, like a router.
In the end, I did buy a copy of the Nim in Action book, available through Manning's early access program. I'd recommend this book to people who are learning Nim, I found it easy to follow and enjoyable to read.
Because Nim has not reached v1 yet, for the moment I'm only using it for experimentation and hobbyist type stuff. But when it actually hits v1, I think that I'd consider using it for real work too.