Great questions! So Nim is garbage collected, but if you really wanted to do memory management like in C you could disable the GC. I haven’t tried that myself, but there’s this article here: https://nim-lang.org/araq/ownedrefs.html if you want to read about it.

As for threads, yes, there is support for them. However, unlike in C where threads have their own stack but share the same heap, each Nim thread has its own heap. To use threads you also need to pass a specific flag during compilation.