We did use some C++ standard library but very sparingly. For example, std::unique_ptr<> was fine, but std::shared_ptr<> was not because of the way it implicitly stores it's reference, so we had our own implementation that exposed the reference.

When I was doing console games this was a must. You would often have restrictions where the container itself should live in a different area of memory to the items which is much easier to manage with your own classes.

Aside, it's embarrassing that all these alternative libraries fail to implement automatic correct signed/unsigned mixing. It's not like it's particularly hard to implement!