There's more to it than just having a fast hashmap: https://www.microsoft.com/en-us/research/wp-content/uploads/2018/03/faster-sigmod18.pdf https://www.microsof

There's more to it than just having a fast hashmap: https://www.microsoft.com/en-us/research/wp-content/uploads/2018/03/faster-sigmod18.pdf https://www.microsoft.com/en-us/research/wp-content/uploads/... (I'd imagine implementing mechanisms for resilient storage and larger than memory data sizes would be the hard parts)