[jstimpfle]

> It is also hard to beat the performance of the STL

If you want to re-create the STL, maybe. But you can make custom data structures tailored to your task at hand instead.

For example, instead of a std::map or std::unordered_map that allocates and initializes each node separately, you could preallocate some of them in a big chunk of memory, hand them out via a bump allocator scheme, and later free them all at once. Instead of a std::sort algorithm, you could use a bucket sort if it's possible in your situation, to improve your asymptotics from O(n log n) to O(n). Etc, etc.

[jart]

There's plenty of papers you can find online where people beat the STL: http://www.cs.cmu.edu/~dga/papers/cuckoo-eurosys14.pdf It's usually because there's some use case or underlying assumption they can make that the STL can't, because the STL is designed to be the best possible one-size-fits-all-approach, which is even further constrained by things like ABI history. So it's always a discouraging sign to hear a software engineer talking about such things as though they're holy, since that'd be like hiring a tailor who uses spandex.