So, the full gist is: Nim uses automatic reference counting with cycle detection. If you want to, you can disable the cycle detection, perhaps only temporarily.

So, the full gist is: Nim uses automatic reference counting with cycle detection. If you want to, you can disable the cycle detection, perhaps only temporarily. The compiler flag for turning GC off doesn't actually turn off all GC, IIRC. It still does automatic reference counting, and it can still do cycle detection, it's just that you need to initiate it manually. The language does have pointers, and will let you do any C-style memory unsafe whatever you want to do with them. However, it doesn't have any library calls that I'm aware of that are equivalent to C's malloc() and free(). You'd have to supply your own. There are also ambitions, of introducing real non-GC memory-safe memory management. Probably something along the lines of how Rust does it. Those haven't come to fruition yet, though. So, long story short, yes you can completely disable GC, but I think that its capabilities on that front are somewhat overstated.