I have been searching for library which implements disk-based replacements for STL containers (most needed - unordered_set), i.e. the data structures on stored on disk rather than the heap, and compiles under C++ 20 or newer.
Also, if there is a good guide on how to change the allocators and algorithms of the standard std containers so that the data is stored on disk, I will be glad to read it and try to implement something similar on my own.
N.B: Please, don't recommend me STXXL which is mentioned in all similar questions, because this library does not implement the containers I need, has not been supported for almost ten years and cannot be compiled on C++20 or newer without full rewriting. Really.