Looks impressive. However, since Nim has such an easy C/C++ FFI you have to consider also all C and C++ APIs. That looks superior even to Go, unless Go's C FFI is as easy as Nim's.

https://github.com/kozross/awesome-c

https://github.com/aleksandar-todorovic/awesome-c

https://cpp.libhunt.com/

https://github.com/fffaraz/awesome-cpp