As to sorting, a lot of libraries use timsort these days since it's more optimal than quicksort in the real world and has nlogn worst case. Or b trees for big s

As to sorting, a lot of libraries use timsort these days since it's more optimal than quicksort in the real world and has nlogn worst case. Or b trees for big storage and sorting, but that's generally a different use case (databases et al). If your threat model is "users who create hash collisions to slowly encumber data operations", you've either royally pissed someone off or you have a very determined competitor. No one who cares about performance would deploy a crypto hash function for a dictionary unless they absolutely had to. You can always add more buckets to reduce collision probability. There's an entire class of hash functions dedicated to non crypto purposes (xxhash, murmur, etc).